ChapterPDF Available

Abstract and Figures

Aquaponics’ potential to transform urban food production has been documented in a rapid increase of academic research and public interest in the field. To translate this publicity into real-world impact, the creation of commercial farms and their relationship to the urban environment have to be further examined. This research has to bridge the gap between existing literature on growing system performance and urban metabolic flows by considering the built form of aquaponic farms. To assess the potential for urban integration of aquaponics, existing case studies are classified by the typology of their building enclosure, with the two main categories being greenhouses and indoor environments. This classification allows for some assumptions about the farms’ performance in their context, but a more in-depth life cycle assessment (LCA) is necessary to evaluate different configurations. The LCA approach is presented as a way to inventory design criteria and respective strategies which can influence the environmental impact of aquaponic systems in the context of urban built environments.
Content may be subject to copyright.
Chapter 21
Aquaponics in the Built Environment
Gundula Proksch, Alex Ianchenko, and Benz Kotzen
Abstract Aquaponicspotential to transform urban food production has been
documented in a rapid increase of academic research and public interest in the
eld. To translate this publicity into real-world impact, the creation of commercial
farms and their relationship to the urban environment have to be further examined.
This research has to bridge the gap between existing literature on growing system
performance and urban metabolic ows by considering the built form of aquaponic
farms. To assess the potential for urban integration of aquaponics, existing case
studies are classied by the typology of their building enclosure, with the two main
categories being greenhouses and indoor environments. This classication allows
for some assumptions about the farmsperformance in their context, but a more
in-depth life cycle assessment (LCA) is necessary to evaluate different congura-
tions. The LCA approach is presented as a way to inventory design criteria and
respective strategies which can inuence the environmental impact of aquaponic
systems in the context of urban built environments.
Keywords Aquaponics classication · Urban aquaponics · Enclosure typologies ·
Greenhouses · Indoor growing · Controlled environment agriculture · Life cycle
assessment
G. Proksch (*) · A. Ianchenko
Department of Architecture, College of Built Environments, University of Washington, Seattle,
WA, USA
e-mail: prokschg@uw.edu
B. Kotzen
School of Design, University of Greenwich, London, UK
e-mail: b.kotzen@greenwich.ac.uk
©The Author(s) 2019
S. Goddek et al. (eds.), Aquaponics Food Production Systems,
https://doi.org/10.1007/978-3-030-15943-6_21
523
21.1 Introduction
Aquaponics has been recognized as one of ten technologies which could change our
livesby merit of its potential to revolutionize how we feed growing urban
populations (Van Woensel et al. 2015). This soilless recirculating growing system
has stimulated increasing academic research over the last few years and inspired
interest in members of the public as documented by a high ratio of Google to Google
Scholar search results in 2016 (Junge et al. 2017). For a long time, aquaponics has
been primarily practiced as a backyard hobby. It is now increasingly used commer-
cially due to strong consumer interest in organic, sustainable farming methods. A
survey conducted by the CITYFOOD team at the University of Washington in July
2018 shows that the number of commercial aquaponic operations has rapidly
increased over the last 6 years. This focused search for aquaponic operations
identied 142 active for-prot aquaponic operations in North America. Based on
online information, 94% of the farms have started their commercial-scale operation
since 2012; only nine commercial aquaponic farms have been in operation for more
than 6 years (Fig. 21.1).
Most of the surveyed aquaponic operations are located in rural areas and are often
connected to existing farms to take advantage of low land prices, available
Fig. 21.1 Existing aquaponic practitioners in North America, 142 commercial companies (red) and
17 research centers (blue), (CITYFOOD, July 2018)
524 G. Proksch et al.
infrastructure, and conducive building codes for agricultural structures. Regardless, a
growing number of aquaponic operations are also located in cities. Due to their
relatively small physical footprint and high productivity, aquaponic operations are
well suited to practice in urban environments (Junge et al. 2017). Surveys undertaken
under the auspices of the European Union (EU) Aquaponics Hub in 2017 identied
50 research centers and 45 commercial companies operating in the European Union
(Fig. 21.2). These companies range in size from small to medium sized.
21.1.1 Aquaponics in Urban Environments
Space is a valuable commodity in cities. Urban farms have to be resourceful to nd
available sites such as vacant lots, existing rooftops, and underutilized warehouses
Fig. 21.2 Aquaponics across Europe: 50 research centers (blue) and 45 commercial companies
(red). (EU Aquaponics Hub 2017)
21 Aquaponics in the Built Environment 525
that are affordable for an agricultural business (de Graaf 2012; De La Salle and
Holland 2010). Urban aquaponic farms need to balance higher production costs with
competitive marketing and distribution advantages that urban locations offer. The
largest benet for locating aquaponic operations in cities is a growing consumer
market with an interest in fresh, high-quality and locally grown produce. When
complying with local regulations for organic produce, urban farms can achieve
premium prices for their aquaponically grown leafy greens, herbs, and tomatoes
(Quagrainie et al. 2018). Unlike hydroponics, aquaponics also has the capacity to
produce sh, further enhancing economic viability in an urban setting which often
has diverse dietary needs (König et al. 2016). Urban aquaponic farms can also save
some operational costs by reducing transportation distance to the consumer and
reducing the need for crop storage (dos Santos 2016).
Urban environmental conditions can also be advantageous for aquaponic farms.
Average temperatures in cities are higher than in rural surroundings (Stewart and
Oke 2010). In colder regions particularly, farms can benet from a warmer urban
climate, which can help reduce heating demand and operational costs (Proksch
2017). Aquaponic farms that are integrated with the building systems of a host
building can further utilize urban resources such as waste heat and CO
2
in exhaust air
to benet the growth of plants as an alternative to conventional CO
2
fertilization.
Urban farms can also help mitigate the negative aspects of the urban heat island
effect during the summer months. The additional vegetation, even if grown in
greenhouses, helps to reduce the ambient temperature through increased evapotrans-
piration (Pearson et al. 2010). In aquaponics, the use of recirculating water infra-
structure reduces overall water consumption for the production of both sh and
lettuce and can, therefore, have a positive effect on the urban water cycle.
Aquaponically-grown produce strives to close the nutrient cycle, thereby avoiding
the production of agricultural run-off. Through smart resource management within
major environmental systems, aquaponics helps to reduce excessive water consump-
tion and eutrophication usually created by industrial agriculture.
21.1.2 Aquaponics as Controlled Environment Agriculture
(CEA)
Traditional agricultural techniques to extend the natural crop-growing season range
from minimal environmental modications,such as temporary hoop houses used on
soil-based elds, to full environmental control in permanent facilities that allow for
year-round production regardless of the local climate (Controlled Environment
Agriculture 1973). The latter strategy is also known as controlled environment
agriculture (CEA) and includes both greenhouses and indoor growing facilities. In
addition to controlling the indoor climate, CEA also signicantly reduces the risk of
crop loss to natural calamities and the need for herbicides and pesticides (Benke and
Tomkins 2017). Most aquaponic operations are conceived as CEA since they
526 G. Proksch et al.
combine two complex growing systems (aquaculture and hydroponics), which both
require controlled growing conditions to guarantee optimal productivity. Addition-
ally, CEA enables year-round production to amortize high investment in aquaponic
infrastructure and achieve premium crop prices at the market outside of the natural
growing season. The performance of aquaponic farm enclosures is highly dependent
on local climate and seasonal swings (Graamans et al. 2018).
As aquaponics is a relatively young discipline, most of the existing research is
focused at the system level for example, studies evaluating the technical integra-
tion of aquaculture with hydroponics in different congurations (Fang et al. 2017;
Lastiri et al. 2018; Monsees et al. 2017). Whilst individual aquaponic system
components and their interactions can still be further optimized for productivity,
their performance within a controlled environment envelope has not been compre-
hensively addressed. Recent research in CEA has begun to assess hydroponic system
performance in tandem with built environment performance, although there is only
one study to date that models aquaponic system performance in a controlled enve-
lope (Benis et al. 2017a; Körner et al. 2017; Molin and Martin 2018a; Sanjuan-
Delmás et al. 2018).
21.1.3 Aquaponics Research Collaborations
The current expansion in interest in aquaponics led to the creation of several interdis-
ciplinary aquaponics related research collaborations funded by the European Union
(EU). The COST FA1305 project, which created the EU Aquaponics Hub
(20142018) brought together aquaponics research and commercial producers to
better understand the state of the art in aquaponics and to generate coordinated
research and education efforts across the EU and around the world. Innovative
Aquaponics for Professional Application (INAPRO) (20142017), a consortium of
17 international partners, aimed to advance current approaches to rural and urban
aquaponics through the development of models and construction of prototypical
greenhouses. The project CITYFOOD (20182021) within the Sustainable Urban
Growth Initiative (SUGI), co-funded by the EU, Belmont Forum, and respective
science foundations, investigates the integration of aquaponics in the urban context
and its potential impact on global challenges of the food-water-energy nexus.
21.2 Classication of Controlled Environment Aquaponics
The term aquaponics is used to describe a wide range of different systems and
operations, greatly varying in size, technology level, enclosure type, main purpose,
and geographic context (Junge et al. 2017). The rst version of the classication
criteria for aquaponic farms included stakeholder objectives, tank volume, and
parameters describing aquaculture and hydroponic system components (Maucieri
21 Aquaponics in the Built Environment 527
et al. 2018). Additional work was undertaken by a large group of researchers to
further dene aquaponics and to present a nomenclature based on international
consensus (Palm et al. 2018). This led to a comprehensive discussion on system
types and scales and most importantly a denition of aquaponics which is: the
majority (> 50%) of nutrients sustaining the optimal plant growth must derive from
waste originating from feeding the aquatic organisms.However, both denitions
focus on the growing systems and do not consider other essential aspects of a
functioning commercial aquaponics farm. As aquaponic operations become part of
local economies, classication criteria identied by interdisciplinary research in
elds like architecture, economics, and sociology will also become essential.
This classication proposal focuses on the emerging eld of commercial
aquaponic operations through the lens of the built environment. The key character-
istics that describe an aquaponic operation fall into four different categories: growing
system, enclosure, operation, and context (Fig. 21.3). These categories for classi-
cation criteria impact one other across scales, where growing system congurations
can affect the contextual performance of the farm as a business, or local market
demands can determine the type of crop grown in the aquaponic system. Some farm
classication criteria are relevant on all scales, such as size,measured in tank
volume, growing area, number of employees, and annual revenue (Table 21.1).
Growing system classication criteria describe the conguration of the
interconnected aquaculture and hydroponic system. This includes specications
for the physical components that enable water and nutrient recirculation (such as
water tanks, lters, pumps, and piping), living organisms that transform available
nutrients at different stages (including sh, plant, and microorganism species) and
Growing System Enclosure Operation Context
Fig. 21.3 Classication criteria for identifying aquaponic farm types
528 G. Proksch et al.
values describing the physical performance of the system, such as temperature, pH
levels, oxygen/carbon content, and electrical conductivity (Alsanius et al. 2017).
Enclosure classication criteria dene characteristics of the buildings that house
the growing systems, at the next scale. Most aquaponic farms use CEA enclosures
that vary by identifying typology (such as a greenhouse or warehouse), structural
system, heating and cooling systems, lighting, ventilation, and humidity control
systems (Benke and Tomkins 2017).
Operations classication criteria describe how each aquaponic farm operates as a
business and farm, which includes human expertise and labor input necessary for
growing and selling produce. Criteria in this section include funding type,
business structure and management, labor requirements and division, marketing
scheme, produce distribution model, and overall purpose of the aquaponics
facility.
Context classication criteria, at the largest scale, describe the geographic loca-
tion, physical context, urban integration, and overall social impact of aquaponic
farms. Context criteria describe how an aquaponic farm is part of the urban food
chain and built environment, capable of inuencing economic growth, social
involvement and large-scale environmental impacts on a city-wide scale (dos
Santos 2016).
21.3 Enclosure Typologies and Case Studies of Commercial
Farms
This further investigation focuses on dening aquaponic classication criteria at the
enclosure level to complement existing system-level denitions. The enclosure types
discussed here work with different construction systems, levels of technological
Table 21.1 Possible classication criteria for aquaponic farm types
Growing system Enclosure Operation Context
Aquaculture system
type
Enclosure typology Purpose Geographical
location
Fish species Structural system Stakeholders Physical context
Water temperature Envelope assembly cover
material
Business model Environmental
impact
Filtration system Heating/cooling systems Labor
distribution
Socioeconomic
context
Feed type Light source Funding type Social impact
Hydroponic system
type
Ventilation system Marketing
scheme
Crop species Host building integration Distribution
model
Water distribution
system
21 Aquaponics in the Built Environment 529
control, passive climate control strategies, and energy sources to achieve an appro-
priate indoor climate. The best application of each enclosure typology depends
primarily on the size of operation, geographic location, local climate, targeted sh
and crop species, required parameters of the systems it houses, and the budget. This
study identies ve different enclosure typologies and denes the characteristics of
indoor spaces that house aquaculture infrastructure.
21.3.1 Greenhouse Typologies
This classication includes four categories of greenhouses medium-tech green-
houses, passive solar greenhouses, high-tech greenhouses, and rooftop greenhouses
that are applicable to commercial-level aquaponic operations (Table 21.2).
Existing greenhouses may not exactly t a single typology, but fall within a spectrum
from medium-tech to high-tech by selectively incorporating active and passive
environmental control techniques.
Medium-Tech Greenhouses Greenhouses with intermediate levels of technology
to control the indoor climate include freestanding or gutter-connected Quonset
(Nissen hut type), hoop house (polytunnel) and even-span greenhouses. They are
usually covered with double polyethylene lm (PE) or rigid plastic panels, such as
acrylic panels (PMMA) and polycarbonate panels (PC). These greenhouses are less
expensive to install, though lm cladding needs to be replaced frequently due to
rapid deterioration caused by constant exposure to UV radiation (Proksch 2017).
These greenhouses protect crops from extreme weather events and to some extent
pathogens, but they offer only a limited level of active climate controls. Instead, they
rely on solar radiation, simple shading systems, and natural ventilation. With their
limited ability to modify growing conditions within a certain range, medium-tech
greenhouses are rarely used for housing aquaponic farms in cold climates. This is
because the high initial investment into the hydroponic and aquaculture components
requires a stable environment and reliable year-round production to be commercially
viable.
Aquaponic operations in warmer climates have successfully demonstrated the use
of medium-tech greenhouses that employ evaporative cooling and simple heating
systems. For example, Sustainable Harvesters in Hockley, Texas, USA uses a simple
Quonset greenhouse (12,000 sf/1110 m
2
) for year-round lettuce production without
relying on extensive supplemental heating or lighting. Ouroboros Farms in Half
Moon Bay, California, USA uses an existing greenhouse (20,000 sf/1860 m
2
)to
produce lettuce, leafy greens, and herbs (Fig. 21.4). Due to the mild climate, the farm
uses primarily static shading and little supplemental heating and cooling. Both
farms, as many smaller medium-tech operations, place their sh tanks in the same
greenhouse space as the hydroponic crop growing system. The farms grow sh
species that tolerate a wide temperature range (tilapia) and shade aquaculture tanks
to prevent overheating and algae growth.
530 G. Proksch et al.
Table 21.2 Comparison of case studies by enclosure typologies
CEA type Case studies
Construction
system Controls
Growing
season
a
and
latitude
Hardiness
zone
b
Medium-
tech
greenhouses
Ouroboros
Farms, Half
Moon Bay,
CA, USA
Existing, gutter-
connected GH
with two even
spans, clad with
single-pane
glass, sh tanks
in GH
Static shading,
shading
curtains
319 days/
10.6 months
10a
30 to 35 F
(20,000
sf/1860 m
2
)
37.5N1.1 to 1 .7
C
Sustainable
Harvesters,
Hockley, TX,
USA
Quonset frame,
multi-tunnel
(3) GH, clad
with PE- lm
and rigid plastic
panels, sh
tanks in GH
Evaporative
cooling, forced
ventilation
272 days/
nine months
8b
15 to 20 F
(12,000
sf/1110 m
2
)
30.0N9.4 to 6 .7
C
Passive
solar
greenhouses
Aquaponic
solar green-
house,
Neuenburg
am Rhein,
Germany
(Chinese) solar
greenhouse,
with adobe wall
as additional
thermal mass,
clad with ETFE
lm, sh tanks
in GH
Custom-built
photovoltaic
modules for
shading and
energy
production
202 months/
6.6 months
8a
1015 F
47.8N12.2 to
9.4
C
(2000
sf/180 m
2
)
Eco-ark
greenhouse at
Finn &
Roots,
Bakerseld,
VT, USA
Solar green-
house, earth
sheltered, steep
angle of south
facing roof
(ca. 60), thick
insulation, spe-
cial solar
collecting glaz-
ing, sh tanks in
northern, sub-
terranean side
Wood-fuelled
radiant heat,
energy curtain,
ventilation
with stack-
effect, supple-
mental LED
lighting
108 days/
3.6 months
4a
30 to 25
F
44.8N34.4 to
31.7 C
(6000sf/
560 m
2
)
High-tech
greenhouses
Superior
Fresh Farms,
Hixton, WI,
USA
Venlo-style,
gutter-
connected,
(20 41 bays),
clad with glass,
sh tanks in
separate
building
Computer-con-
trolled CEA
environment,
supplemental
LED lighting,
122 days/
4.1 months
4b
25 to
20 F
(123,000
sf/11,430 m
2
)
44.4N31.7 to
28.9 C
Blue Smart
Farms,
Cobbitty,
NSW,
Australia
Venlo-style,
gutter-
connected,
(14 18 bays),
clad with glass,
two-story con-
struction, sh
tanks on the
lower level
Computer-con-
trolled CEA
environment
biological pest
control
300 days/
10 months
9b
25 to 30 F
(53,800
sf/5000 m
2
)
34.0S3.9 to
1.1 C
(continued)
Passive Solar Greenhouses This greenhouse type is designed to be solely heated
by solar energy. Substantial thermal mass elements, such as a solid north-facing
wall, store solar energy in form of heat that is then re-radiated during colder periods
at night. This approach buffers air temperature swings and can reduce or eliminate
the need for fossil fuels. Solar greenhouses have a transparent south-facing side and
an opaque, massive, highly insulated north-facing side. The integration of large
volumes of water in form of sh tanks is an asset for the thermal performance of this
greenhouse type. Furthermore, the tanks can be located in areas of the greenhouse
that are less suited for plant cultivation or partly submerged into the ground for
added thermal stability.
Table 21.2 (continued)
CEA type Case studies
Construction
system Controls
Growing
season
a
and
latitude
Hardiness
zone
b
Rooftop
greenhouses
Ecco-jäger
Aquaponik
Dachfarm,
Bad Ragaz,
Switzerland
Venlo-style,
gutter-
connected,
(7 13 bays),
clad with glass,
sh tanks on the
lower level
CEA environ-
ment, supple-
mental LED
lighting, use of
exhaust heat
from cooling
facility
199 days/
6.6 months
7b
5to10F
47.0N15.0 to
12.2 C
(12,900
sf/1200 m
2
)
BIGHs
Ferme abat-
toir, Brussels,
Belgium
Venlo-style,
gutter-
connected,
(15 10 bays),
clad with glass,
sh tanks on the
lower level
CEA environ-
ment, supple-
mental LED
lighting
224 days/
7.3 months
8b
15 to 20 F
50.8N9.4 to
6.7C
(21,600
sf/2000 m
2
)
Indoor
growing
spaces
Urban
Organics,
Schmidts
Brewery,
St. Paul, MN,
USA
Steel-frame
warehouse,
highly insu-
lated, stacked
growing, sh
tanks in sepa-
rate space
Fluorescent
UV lighting,
computer-
controlled
CEA
environment
140 days/
4.7 months
4b
25 to
20 F
31.7 to
28.9 C
45.0N
(87,000
sf/8080 m
2
)
Nutraponics,
Sherwood
Park, AB,
Canada
Steel-frame
warehouse,
highly insu-
lated, stacked
growing, sh
tanks in sepa-
rate space
LED lighting,
computer-
controlled
CEA
environment
121 days/
4 months
4a
30 to
25 F
(10,800
sf/1000 m
2
)
53.5N34.4 to
31.7 C
a
Frost-free growing season, National Gardening Association, Tools and Apps, https://garden.org/
apps/calendar/
b
Based on the USDA Hardiness Zone Map, which identies the average annual minimum winter
temperature (19762005), divided into 10F zones. Plant Maps, https://www.plantmaps.com/
index.php
532 G. Proksch et al.
The Aquaponic solar greenhouse (2000 sf/180 m
2
), developed and tested by
Franz Schreier, has proven as a suitable environment for housing a small aquaponic
system in southern Germany. The greenhouse collects solar energy through its
south-facing arched roof and wall clad with ethylene tetrauoroethylene (ETFE)
lm. Heat is stored in partially submerged sh tanks, oor, and adobe-clad northern
wall to be dissipated at night. The greenhouses custom-built photovoltaic
(PV) panels transform solar radiation into power. Located in the colder climate of
Vermont, USA, the Eco-Ark Greenhouse at the Finn & Roots farm (6000 sf/560 m
2
)
houses an aquaponic system that works with a similar passive solar approach. The
greenhouse has a steep (approx. 60
) south-facing transparent roof with special solar-
collecting glazing (Fig. 21.5). Its highly insulated, opaque northern side is sub-
merged into a hillside and houses the sh tanks. In addition to these passive controls,
the Eco-Ark has a radiant oor heating that supplements heating during the coldest
seasons.
High-Tech Greenhouses Venlo-style, high-tech greenhouses that feature a high
level of technology to control the indoor climate are the standard for commercial-
scale hydroponic CEA. High-tech greenhouses are characterized by computerized
controls and automated infrastructure, such as automatic thermal curtains, automatic
lighting arrays, and forced-air ventilation systems. These technologies enable a high
level of environmental control, though they come at the cost of high energy
consumption.
Fig. 21.4 Ouroboros Farms (Half Moon Bay, California, USA)
21 Aquaponics in the Built Environment 533
Some large-scale commercial aquaponic farms use this greenhouse typology for
their plant production, such as Superior Fresh farms, located in Hixton, Wisconsin,
USA (123,000 sf/11,430 m
2
), with the aquaculture systems housed in a separate
opaque enclosure. Automated supplemental LED lighting and heating enables
Superior Fresh farms to cultivate leafy greens year-round despite lack of daylight
in the winter, where the natural, frost-free growing season lasts only 4 months.
Automated systems for internal climate control allow high-tech greenhouses to be
operated anywhere in the world Blue Smart Farms greenhouse uses an array of
sensors to optimize shading during hot Australian summers.
Thanet Earth, the largest greenhouse complex in the UK, is located in the
southeast of England. Its ve greenhouses cover more than 17 acres (7 hectares)
each, growing tomatoes, peppers, and cucumbers using hydroponics (Fig. 21.6).
This enterprise is powered by a combined heat and power system (CHP) that
provides power, heat, and CO
2
for the greenhouses. The CHP system operates
very efciently and channels excess energy to the local district by feeding it into
the local power supply grid. In addition, computer-controlled technologies such as
energy curtains, high-intensity discharge supplemental lighting, and ventilation
regulate the indoor growing conditions.
Rooftop Greenhouses This most recent type includes greenhouses built on top of
host buildings, either as retrots of existing structures or as part of new construction.
Due to high land costs, saving space is increasingly important to aquaponic farms in
urban contexts. Connecting a greenhouse to an existing building is one strategy for
urban farmers looking to revitalize underused space and nd a central location in the
city. Rooftop greenhouses are already used by commercial-scale hydroponic
growers but are a relatively rare enclosure type for aquaponic farms due to the
Fig. 21.5 Eco-Ark Greenhouse at Finn & Roots Farm (Bakerseld, Vermont, USA)
534 G. Proksch et al.
additional weight of water which can strain existing structures beyond their loading
capacity. The few rooftop aquaponic farms that currently exist prioritize lightweight
water distribution systems (nutrient lm technique or media-based growing rather
than deep water culture) and locate their sh tanks on the level below the crop
growing space due to relatively decreased demand for natural light.
Two rooftop farms with high-tech aquaponic systems have recently opened in
Europe. Both consulted with Efcient City Farming (ECF) farm systems consul-
tants in Berlin. Ecco-jäger Aquaponik Dachfarm in Bad Ragaz, Switzerland sits on
top of a distribution center of a family-owned produce company. The Venlo-style
rooftop greenhouse (12,900 sf/1200 m
2
) is located on a two-story depot building;
the sh tanks are installed on the oor below the greenhouse. By growing leafy
greens and herbs on their rooftop, Ecco-jäger reduces the need for transportation
and can offer produce immediately after harvest. In addition, the farm takes
advantage of waste heat generated by its cold storage to heat the greenhouse.
BIGHs Ferme Abattoir (21,600 sf/2000 m
2
) is a larger version of a similar
Venlo-style rooftop greenhouse (Fig. 21.7), which occupies the roof of the Foodmet
market hall in Brussels, Belgium. These early examples point to further potential to
optimize both aquaponic and envelope performance through connecting water,
energy, and air ows between farm and host building, known as building-integrated
agriculture (BIA). Currently, research is being done on the agship hydroponic
integrated rooftop greenhouse located on the building shared by the Institute
of Environmental Science and Technology (ICTA) and the Catalan Institute of
Paleontology (ICP) at the Autonomous University of Barcelona (UAB) to dermine
Fig. 21.6 Thanet Earth, state of the art greenhouses with combined heat and power provision, (Isle
of Thanet in Kent, England, UK)
21 Aquaponics in the Built Environment 535
the benets of full building integration, although no such example exists in the eld
of aquaponics to determine the benets of full building integration, although no
such example exists in the eld of aquaponics.
21.3.2 Indoor Growing Type
Indoor growing spaces rely exclusively on articial light for plant production. Often,
these growing spaces are highly insulated and clad in an opaque material, originally
intended as storage or industrial manufacture rooms. Indoor growing spaces typi-
cally have better insulation than greenhouses due to the envelope material, though
cannot rely on daylighting or natural heating. The assumption is that this typology is
better suited to extreme climates, where temperature swings are of larger concern
than lighting (Graamans et al. 2018), though more conclusive research is needed.
Urban Organics operates two commercial-scale indoor growing aquaponic farms
within two refurbished breweries in the industrial core of St. Paul, Minnesota, USA.
The two farms cultivate leafy greens and herbs in stacked growing beds illuminated
by uorescent grow lights (Fig. 21.8). Their second site allows Urban Organics to
tap into the brewery infrastructure around an existing aquifer; the aquifer water
needs minimal treatment and is supplied at 10 C to arctic char and rainbow trout
Fig. 21.7 BIGH Ferme Abattoir with the high-tech greenhouse in the background (Brussels,
Belgium)
536 G. Proksch et al.
tanks. Using existing structures lowered construction costs for Urban Organics and
offered the opportunity to revitalize a struggling area of the city. In an even colder
climate, Nutraponics grows leafy greens in a warehouse on a rural parcel 40 km
outside Edmonton, Alberta, Canada. Since local produce is highly dependent on
seasonal temperature swings, Nutraponics gains a competitive edge in the market by
employing LED lighting to accelerate crop growth year-round (Fig. 21.9).
21.3.3 Enclosures for Aquaculture
The enclosures for the aquaculture component of aquaponic operations are techni-
cally not as demanding as the enclosure design for the hydroponic components since
sh do not require sunlight to thrive. Nevertheless, control over indoor growing
conditions enables farmers to optimize growth, reduce stress, and draw up precise
schedules for sh production which gives their stock a competitive edge in the
market (Bregnballe 2015). Aquaculture space enclosures are mainly required to keep
water temperatures stable. Fish tanks should be able to support comfortable water
temperature ranges for specicsh species, warm-water sh 7586F (2430C)
and cold-water sh 5474F (1223C) (Alsanius et al. 2017). Water and room
temperature can be controlled most efciently if sh tanks are housed in well-
Fig. 21.8 Urban Organics (St. Paul, Minnesota, USA)
21 Aquaponics in the Built Environment 537
insulated space with few windows to minimize solar gains during the summer
months and temperature losses when the outside temperature drops (Pattillo 2017)
as demonstrated in the set-up of the INAPRO enclosure. The large volume of water
required for sh cultivation needs to be considered from an architectural perspective,
as it carries consequences for structural and conditioning systems within a building.
21.4 Assessing Enclosure Typologies and Possible
Applications
The actual performance of aquaponic farms depends on many case-specic factors.
Some preliminary conclusions about enclosure typologiesadvantages, challenges,
and possible applications can be drawn from the comparison of a relatively small set
of case studies. An empirical study of a more signicant number of existing case
studies will be needed to establish a correlation between enclosure type, geographic
location, and commercial success.
Medium-tech greenhouses offer a commercially-feasible option for aquaponic
operations only in temperate climates with mild winters and moderate summers, due
to their limited environmental control capability. In locations that do not require
much heating and cooling, farms using this greenhouse typology can operate in a
resource-efcient manner with lower upfront investment for their enclosure. These
farms usually operate on a lower budget and include the sh tanks in the same
Fig. 21.9 Nutraponics (Sherwood Park, Alberta, Canada)
538 G. Proksch et al.
greenhouse, which limits their selection of sh species to those with a large temper-
ature tolerance and draws their commercial focus to the production of lettuce, leafy
greens, and herbs.
Passive solar greenhouses rely on passive systems, specically the use of thermal
mass, to control the indoor climate. The use of this typology for aquaponic systems is
advantageous since the large volume of water in the sh tanks provides additional
thermal mass. Due to their energy efciency, they are often used in northern latitudes
where conventional greenhouses would require a high level of supplemental heating.
However, operating any greenhouse in those regions relies on the use of supple-
mental lighting due to low light levels and short daylight hours during the winter
season. Although passive solar greenhouses in Europe and North America are
currently used on a small experimental scale, the more general successful application
of these single-slope, energy-efcient greenhouses on 1.83 million acres (0.74
million hectares) of farmland in China shows that this typology can be successfully
implemented on a large scale (Gao et al. 2010).
High-tech greenhouses, especially large Venlo-style, gutter-connected systems,
are the industry standard for commercial hydroponic production. The largest well-
funded commercial aquaponic farms use this typology for their hydroponic growing
systems in conjunction with a separate enclosure for their aquaculture infrastructure.
This setup guarantees the highest level of environmental control as well as crop and
sh productivity. Technically, this type of greenhouse can be operated anywhere, as
long as the revenue produced pays for the high energy and operation costs in extreme
climates. However, this type of operation may not be environmentally sensitive in
some northern latitudes due to the extensive need for heating and supplemental
lighting. The exact environmental footprint of a high-tech greenhouse can only be
assessed on a per-project basis and depends mostly on the quality of energy sources
used for supplemental heat and light.
Most rooftop greenhouses are Venlo-style high-tech greenhouses constructed on
rooftops. Whilst similar benets and challenges apply, the construction of rooftop
greenhouses is even more expensive than that of regular high-tech greenhouses,
primarily due to building codes and architectural requirements. The structural system
of rooftop greenhouses is often over-dimensioned to comply with building codes for
commercial ofce buildings, which are stricter than building code requirements for
agricultural structures. Furthermore, aquaponic operations on rooftops need addi-
tional infrastructure to access the roof and comply with re and egress regulations,
which has generated a sprinkler equipped-greenhouse in a recent example (Proksch
2017). The most promising application of rooftop greenhouses is on top of host
buildings in urban centers. Urban roofs often offer ample access to sunlight, which
greenhouses require to function effectively a resource that is usually lacking, or at
least is not consistent due to shadowing, at ground level in dense urban areas
(Ackerman 2012). If purposefully designed, host buildings can offer other resources
such as exhaust heat and CO
2
that can make the operation of a rooftop aquaponic
farm more feasible. This type of integration with the host building can generate
energy and environmental synergies that improve the performance of both green-
house and host building.
21 Aquaponics in the Built Environment 539
Indoor growing spaces depend entirely on articial lighting and active control
systems for heating, cooling, and ventilation, which results in a high level of energy
consumption, environmental footprint, and operation cost. This typology is most
applicable in areas with cold winters and short growing seasons, where the natural
exposure to sunlight and heat gain is low and extensive supplementation is needed to
operate a commercial aquaponics greenhouse. The use of an opaque enclosure
allows high levels of insulation, which reduces heat loss during winter months and
provides autonomy from external temperature swings. Besides its dependence on
electrical lighting, indoor growing exceeds the productivity of greenhouses as
measured in other resources, such as water, CO
2
, and land area (Graamans et al.
2018). Additionally, the production per unit of land area can be much higher through
the use of stacked growing systems. Regarding the urban integration of aquaponics
in cities, indoor grow spaces allow for the adaptive reuse of industrial buildings and
warehouses, which can reduce the up-front cost for the construction of the enclosure
and support the integration of aquaponic farms in underserved neighborhoods.
The Innovative Aquaponics for Professional Applications (INAPRO, 2018) pro-
ject set-up included the comparison of the same state of the art aquaponic system and
greenhouse technology, across a number of sites in Germany, Belgium, and Spain.
The aquaponics system located in China was housed in a passive solar greenhouse.
The INAPRO aquaponics facilities in Europe utilized a glass-clad greenhouse type
for plant production and an industrial type shed component for sh tanks and
ltration units (Fig. 21.10). The INAPRO project demonstrates that greenhouse
Fig. 21.10 INAPRO aquaponics enclosure with two sections, opaque for sh and greenhouse for
plants (Murcia, Spain)
540 G. Proksch et al.
technologies need to be adapted and chosen to suit local climate conditions. The
Spanish INAPRO team found, that the selected enclosure was well suited for the
cooler northern Europe regions, but not the warmer, Mediterranean regions in
southern Europe. This observation highlights the importance of more research on
the performance of greenhouses typologies to advance the eld of commercial
aquaponics operations.
While the comparison of the different typologies reveals certain performance
patterns between typology, location, and investment (Table 21.3), for a comprehen-
sive understanding of farm performance and environmental impact, a more robust
system for the analysis and design of farm enclosures is needed.
21.5 Impact Assessment as a Design Framework
The growth of aquaponics and generalized claims that aquaponics is more sustain-
able than other forms of food production has stimulated discussion and research into
how sustainable these systems actually are. Life cycle assessment (LCA) is one key
quantication method that can be used to analyze sustainability in both agriculture
and the built environments by evaluating environmental impacts of products
throughout their lifespan. For a building, an LCA can be divided into two types of
impact embodied impact which includes material extraction, manufacture, con-
struction, demolition and disposal/reuse of said materials, and operational impact
which refers to building systems maintenance (Simonen 2014). Similarly,
conducting an assessment of an agricultural product can be also divided into the
structural impact of the building envelope and system infrastructure, production
impact associated with continuous cultivation and post-harvest impact of packaging,
storage, and distribution (Payen et al. 2015). Conducting an LCA of an aquaponic
farm requires the simultaneous understanding of both building and agricultural
impacts since there is an overlap in the envelopesoperational phase with a crops
production phase. The way a building operates its heating, cooling, and lighting
systems directly inuences the cultivation of the crop; conversely, different types of
crops require different environmental conditions. Numerous studies exist comparing
LCA results for different building types situated in different contexts (Zabalza
Bribián et al. 2009). Similarly, LCA has been used by the agricultural sector to
compare efciencies for different crops and cultivation systems (He et al. 2016;
Payen et al. 2015). Evaluating the performance of controlled environment agricul-
ture and aquaponics in particular requires a skillful integration of the two method-
ologies into one assessment (Sanyé-Mengual 2015).
The proposed aquaponic farm LCA framework (Fig. 21.11) is intentionally broad to
capture a wide range of farm typologies found in the eld. In order to apply the results
of LCA to existing farms, factors such as climate and economic data must be included
to validate environmental assessment (Goldstein et al. 2016;Rothwelletal.2016)
The following section discusses a collection of aquaponic farm enclosure design
strategies based on the LCA inventory of aquaponic farms that synthesizes existing
21 Aquaponics in the Built Environment 541
Table 21.3 Comparison of controlled environment agriculture typologies
CEA type Benets Challenges Cost and revenue
a
Medium-
tech
greenhouses
Relies almost entirely on
solar energy, low addi-
tional energy requirement
Limited environmental con-
trol options, susceptible to
environmental uctuations
Lower up-front/
construction cost,
(approx. 30100
$/m
2
)
Less reliance on
non-renewable materials
and energy sources
Only applicable to sh
species with a large tem-
perature tolerance, (if tanks
are in the greenhouse)
Passive
solar
greenhouses
Relies on passive systems,
uses thermal mass, (includ-
ing the sh tanks) to buffer
temperature swings
Control with passive sys-
tems needs more experience
and deliberate design
Lower up-front/
construction cost,
(approx. 30100
$/m
2
)
Low energy consumption,
potentially without the
need for any fossil fuel
Require supplemental
lighting, if located in
northern latitudes due to
low light levels
High-tech
greenhouses
Highest levels of controls Relies on active systems for
heat, cooling, ventilation
and supplemental lighting
High up-front/
construction cost,
(approx. 100200
$/m
2
and more)
High productivity with the
potential to scale up
High energy consumption
and operation cost
Rooftop
greenhouses
Highest levels of controls Relies on active systems for
heat, cooling, ventilation
and supplemental lighting
Very high up-front/
construction cost
(approx. 300500
$/m
2
)
High productivity
Potential for energetic and
environmental synergies, if
integrated with host
building
High energy consumption
and operation cost
Requires code compliance
at the level of commercial
ofce buildings
Transport of supplies to
rooftop is an infrastructural
challenge
Indoor
growing
spaces
Adaptive reuse of industrial
buildings possible
Depends entirely on electri-
cal lighting and active con-
trol systems for heating,
cooling, and ventilation
Up-front/construc-
tion cost can be
lower if existing
building can be used
High productivity per unit
of footprint though stacked
growing systems
High energy consumption
and operation cost
Cost depends also
on the growing sys-
tem, stacking multi-
ple levels
High level of insulation
possible
Reduced heat loss during
winter months
a
Based on Proksch (2017)
542 G. Proksch et al.
InfrastructureProductionDistribution
Extraction Manufacture
Manufacture
Tran sp or t
Extraction Transport Construction Maintenance
Substrate Fertilizer s
Fish feed
HeatingInfrastructure
construction
Cooling Lighting Pumping
Demolition
Waste
management
Waste
management
Waste
management
Energy
Energy
Water
Energy Materials
Materials
PackagingProduce
harvesting
Consumption
Transportation Storage
Built Envir onment Proces ses and Inputs
Food System Processes and Inputs
Combined Processes and Inputs
One-Time Processes and Inputs
Recurring Processes and Inputs
PROCESSES INPUTS
Fig. 21.11 Example of an integrated LCA process including building and aquaponic system
performance. (Based on Sanyé-Mengual et al. 2015).
21 Aquaponics in the Built Environment 543
literature with case studies and suggests directions for future work. The unique
integration of aquaponic and building-related impacts is of particular interest.
21.5.1 Embodied Impacts: Embodied Energy and Embodied
Carbon
Structure Materials and Construction Embodied energy is the calculation of the
sum of energy used to extract, rene, process, transport, produce, and assemble a
material or product. Embodied carbon is the amount of CO
2
emitted to produce the
same material or product. Compared to conventional open-eld agricultural opera-
tions, the embodied impact of a controlled environment growing system is greater
due to increased material extraction and manufacture at the construction stage
(Ceron-Palma et al. 2012). For example, in the ICTA-ICP rooftop greenhouse, the
structure of the envelope generates 75% more Global Warming Potential (GWP)
than a soil-based multi-tunnel greenhouse structure due to the quantity of polycar-
bonate used in construction (Sanyé-Mengual et al. 2015). Similarly, a building-
integrated greenhouse simulation situated in Boston resulted in increased environ-
mental impacts at the construction stage, due to the extraction of iron ores for the
manufacture of structural steel (Goldstein 2017). Embodied impacts associated with
controlled environment envelopes can be mitigated through smart material use
(given that building code adjustments are made to avoid over-sizing structural
members) but would nevertheless surpass those of traditional agriculture. Growing
food in a constructed envelope will always be more resource-intensive at the
beginning compared to simply planting vegetables in an open eld, though will
also dramatically increase the amount of food that can be produced per area footprint
in the same timeframe.
To avoid structure-related environmental impacts, some aquaponic operations
make use of existing buildings instead of constructing a new envelope. Urban
Organics in St. Paul, Minnesota, USA refurbished two brewery buildings as their
indoor growing spaces. In another example of adaptive reuse, The Plant in Chicago,
Illinois, USA operates its food incubator and urban farm collective in a 1925 factory
building previously used by Peer Foods as a meat-packaging facility (Fig. 21.12).
Existing insulation and refrigeration equipment were repurposed to control temper-
ature uctuations in the experimental aquaponic facility.
Aquaponic Equipment and Substrate When integrated into buildings, the mate-
rial choice for aquaponic tanks becomes an important design consideration, since it
may limit assembly and transport into the building. For example, polyethylene parts
can be assembled on-site using plastic welding, but this is not possible with berglass
parts (Alsanius et al. 2017). Furthermore, the manufacture of aquaponic system
equipment can be a signicant contributor to overall environmental impact for
544 G. Proksch et al.
example, glass ber-reinforced polyester used for the 100 m
3
water tank at the ICTA-
ICP rooftop greenhouse is responsible for 1025% of environmental impact at the
manufacturing stage (Fig. 21.13). The choice of substrate for plants in an aquaponic
system has a weight ramication for the structure of the host building, but also
contributes to environmental impact. In a recent study done on aquaponics integrated
with living walls, mineral wool, and coconut ber performed comparably, despite one
being compostable and the other being single-use (Khandaker and Kotzen 2018).
Structure and Equipment Maintenance Initial material selection for aquaponic
equipment and envelope components determines the long-term upkeep of aquaponic
farms. Manufacturing more durable materials such as glass or rigid plastics requires
a greater initial investment of environmental resources than plastic lms; however,
lms require replacement more frequently for example, glass is expected to remain
functional for 30+ years, whilst more conventional coated polyethylene lm can
only last 35 years before becoming too opaque (Proksch 2017). Depending on the
intended lifespan of an aquaponic system envelope, it may be more advantageous to
choose a material with a shorter lifespan, and a lesser manufacturing impact. ETFE
lm used in the Aquaponic solar greenhouse is a promising compromise between
longevity and sustainability, although further research is needed. Standard
aquaponic equipment consists of water tanks and piping. Piping for aquaponic
systems is often manufactured from PVC, which produces a signicant environ-
mental impact in its manufacturing process but does not require replacement for up
to 75 years. Some aquaponic suppliers offer bamboo as an organic alternative.
Fig. 21.12 The Plant (Chicago, Illinois, USA)
21 Aquaponics in the Built Environment 545
21.5.2 Operational Impacts
Energy In 2017, 39% of total energy consumption within the United States
corresponded to the building sector (EIA). The agricultural sector accounted for
approximately 1.74% of total U.S. primary energy consumption in 2014, relying
heavily on indirect expenditures in the form of fertilizers and pesticides (Hitaj and
Suttles 2016). Energy efciency is a well-established eld of research within both
the built environment and agriculture, often dening the operational impacts of a
product, building, or farm in the overall LCA (Mohareb et al. 2017). Integrating
building and agricultural energy use can optimize the performance of both (Sanjuan-
Delmás et al. 2018).
Heating Energy requirements for heating growing spaces are of particular interest
in the northern climates, where extending a naturally short growing season gives
building-integrated aquaponic farms a competitive edge in the market (Benis and
Ferrão 2018). However, in colder climates, energy consumption by active heating
systems is a signicant contributor to overall environmental impact in an
Fig. 21.13 Building section with rooftop greenhouses by Harquitectes, ICTA-ICP building
(Bellaterra, Spain)
546 G. Proksch et al.
assessment of conditioned growing spaces in Boston, Massachusetts, heating costs
neutralized the benets of eliminating food miles in the urban food chain (Benis et al.
2017b; Goldstein 2017). This does not hold true in Mediterranean climates, where
climatic conditions are conducive to agriculture and where nearly year-round and
conventional greenhouse structures can rely on passive solar heating (Nadal et al.
2017; Rothwell et al. 2016).
In both cold and warm climates, integrating controlled environment growing
systems on existing rooftops can provide insulation to the host building a farm
in Montreal, Quebec reports to capture 50% of the greenhouse heating needs from
the existing host structure, thereby reducing heating load (Goldstein 2017). Lighting
systems can also be partially responsible for satisfying heating demand in interior
vertical growing applications such as plant factories or shipping containers (Benis
et al. 2017b).
Residual heat capture is another promising design strategy that can optimize the
performance of both the host structure and the growing system. Post-occupancy
studies of the experimental rooftop greenhouse at the ICTA-ICP in Bellaterra, Spain
indicate that the integration of the building with the greenhouse delivered an
equivalent carbon savings of 113.8 kg/m
2
/year compared to a conventional free-
standing greenhouse heated with oil (Nadal et al. 2017). Without intervention from
active heating, ventilation and air conditioning (HVAC) systems, the thermal mass
of the host laboratory/ofce building raised the greenhouse temperature by 4.1C
during the coldest months, enabling the cultivation of the tomato crop year-round.
Cooling In Mediterranean and tropical climates, articial cooling is often a require-
ment to grow produce year-round. In a rooftop greenhouse simulation, cooling loads
represented up to 55% of total farm energy demands in Singapore and in the more
temperate climate of Paris, 30% (Benis et al. 2017b). Cooling energy demands are
especially high in arid climates, which can benet the most from cutting conventional
transportation costs for perishable produce (Graamans et al. 2018; Ishii et al. 2016).
Evaporative cooling, fog cooling, and shading are some strategies for lowering
temperatures in aquaponic farms and improving farm performance in terms of yield.
Building-integrated aquaponic systems have the advantage of storing thermal
mass in sh tanks to alleviate cooling as well as heating loads. In cases where this
mode of passive cooling does not satisfy the cooling demand, evaporative cooling is
most commonly used. The Sustainable Harvesters greenhouse produces lettuce for
the Houston, Texas, USA area year-round by using a fan and pad cooling system, a
subset of evaporative cooling technology. Hot air from outside the envelope rst
passes through a wet cellulose medium before entering the growing space. As a
result, the interior air is cooler and more humid. Evaporative cooling is most
effective in dry climates but requires high water use, which may be a limitation to
farms in arid areas of the world.
Fog cooling is an alternative strategy. In a fog-cooled greenhouse, plants are
periodically misted with water from overhead sprinklers/misters until the space
reaches the desired temperature for cultivation. Fog cooling uses less water than
evaporative cooling but increases the relative humidity of a growing space. If paired
21 Aquaponics in the Built Environment 547
with the right ventilation strategy, fog cooling can be a water-saving technology
particularly suited to arid regions (Ishii et al. 2016). Additionally, fog cooling
decreases the rate of evapotranspiration in plants, which is critical to optimizing
plant metabolism in aquaponic systems (Goddek 2017). The agship greenhouse of
Superior Fresh farms uses a computerized fog-cooling system to maintain cultivation
temperatures during the hot season.
Shading devices can also contribute to lowering greenhouse temperatures. Tra-
ditionally, the seasonal lime whitewashing of greenhouses was used to reduce solar
radiation levels during the hottest months (Controlled Environment Agriculture
1973). However, shading can be integrated with other building functions. A prom-
ising shading strategy is using semi-transparent photovoltaic modules to simulta-
neously cool the space and produce energy (Hassanien and Ming 2017). The
Aquaponic solar greenhouse combines its photovoltaic array with shading function-
ality; it uses rotating aluminium panels as shading devices that operate as solar
collectors with the help of mounted photovoltaic cells. The integrated photovoltaic
system then transforms excess solar radiation into electrical energy.
Lighting The main advantage of greenhouses over indoor growing spaces is their
ability to capitalize on daylight to facilitate photosynthesis. However, farms in
extreme climates may nd that satisfying heating or cooling loads for a transparent
envelope is not nancially feasible; in this case, farmers may choose to cultivate crop
in indoor growing spaces with an insulated envelope (Graamans et al. 2018).
Aquaponic farms that operate in indoor growing spaces rely on efcient electrical
lighting to produce crops.
Many advances in contemporary farm lighting originated in Japanese plant
factories, used to optimize plant yields in dense hydroponic systems by replacing
sunlight with engineered light wavelengths (Kozai et al. 2015). Currently, LED
lighting is the most popular choice for electrical horticultural lighting systems. They
are 80% more efcient than high-intensity discharge lamps and 30% more efcient
than their uorescent counterparts (Proksch 2017). LED lighting continues to be
investigated to optimize energy efciency and crop yield (Zhang et al. 2017). Large-
scale greenhouses like Superior Fresh, Wisconsin, USA rely on computerized,
supplemental lighting regimes to extend the photosynthesis period of its crop in
northern latitudes.
Energy Generation Constrained by the same factors as all CEA, the energy
management of an aquaponic farm depends on exterior climate, crop selection, the
production system, and structure design (Graamans et al. 2018). Growing produce
through aquaponics is not inherently sustainable if not managed properly all of the
factors above can affect energy efciency for the better or worse (Buehler and Junge
2016). In many cases, CEA is more energy-intensive than conventional open-eld
agriculture; however, higher energy expenditures may be justied if the way we
source energy shifts toward renewable sources and efcient strategies for heating,
cooling, and lighting are incorporated into the design of the farm.
Photovoltaic (PV) power generation can play an important part in offsetting
operational impacts for controlled environment aquaponics, reducing environmental
548 G. Proksch et al.
strain. In an example of a high-tech greenhouse in Australia, using energy from a PV
array caused a 50% reduction in lifecycle greenhouse gas emissions compared to the
conventional grid scenario (Rothwell et al. 2016). Renewable energy generation can
be combined with aquaponic farms, space permitting for example, the Lucky Clays
Fresh aquaponic greenhouse on a rural farm in North Carolina runs on energy
generated by wind turbines and photovoltaic panels that are situated elsewhere on
the owners land parcel.
Water Water use efciency has been often cited as a major benet of CEA and
hydroponic systems (Despommier 2013; Specht et al. 2014). Aquaponic systems are
even better suited to increase water efciency where 1 kg of sh produced in a
conventional aquaculture system requires between 2500 and 375,000 L, the same
amount of sh raised in an aquaponic system requires less than 100 L (Goddek et al.
2015). Rainwater capture and greywater reuse have been proposed as two strategies
to offset the watershed impacts of operating a hydroponic or aquaponic farm even
further. At the existing ICTA-ICP greenhouse, 8090% of the water needs for the
production of tomatoes in an aggregate hydroponic system were covered by rain-
water capture within a year of operation (Sanjuan-Delmás et al. 2018). However, the
ability of rainwater capture to meet crop demand depends on the climatic context. In
a study evaluating the viability of rooftop greenhouse production on existing retail
parks in eight cities around the world, seven met crop self-sufciency through
rainwater capture only Berlin did not (Sanyé-Mengual et al. 2018).
Some existing CEA facilities already reuse greywater to improve efciency
(Benke and Tomkins 2017). However, greywater reuse in an urban context is
currently limited due to lacking regulatory support and currently-lacking research
on the health risks of using greywater in agriculture. A pilot of greywater reuse, the
Maison Productive in Montréal collects greywater from household uses to supplement
its rainwater collection to irrigate gardens and a communal greenhouse for food
production that nine residential units share (Thomaier et al. 2015). With further
advances in policy on the treatment of greywater, building-integrated aquaponics
can tap into the existing water cycle instead of relying on municipal sources.
From an architectural standpoint, water distribution in an aquaponic system is
likely to present a structural challenge. Aquaponic sh tanks weigh more than
hydroponic grow beds and may limit what types of structures are feasible for
retrotting an aquaponic farm. The growing medium also requires consideration
deep water culture (DWC) systems require a large and heavy volume of water, whilst
nutrient lm technique (NFT) systems are lightweight but expensive to manufacture
(Goddek et al. 2015).
Nutrients Compared to conventional open-eld farming, CEA reduces the need for
fertilizers and pesticides, as the farmer can physically separate the crop from harsh
external conditions (Benke and Tomkins 2017). However, due to the density of an
aquaponic system, plant or sh diseases can spread quickly if a pathogen inltrates
the space. Preventative options such as the use of predator insects or tight environ-
mental control measures such as a bufferentryways can avert this risk (Goddek
et al. 2015).
21 Aquaponics in the Built Environment 549
The integration of different sh and crop nutrient needs is a challenge in single-
recirculating aquaponic systems (Alsanius et al. 2017). Generally, plants require
higher nitrogen concentrations than sh can withstand and careful crop and sh
selection can match nutrient requirements to optimize yields, but is still difcult to
achieve. Decoupled systems (DRAPS) have been proposed to separate the aquacul-
ture water cycle from the hydroponic one to achieve desired nutrient concentrations,
but is not yet commonly applied in commercial farms (Suhl et al. 2016). Urban
Organics based in St. Paul, Minnesota, USA chose to develop a DRAPS system for
their second farm to optimize both crop and sh yields and avoid crop loss in case of
nutrient imbalances within sh tanks. ECF Farm in Berlin, Germany, and Superior
Fresh farms in Wisconsin, USA also operate decoupled systems to optimize sh and
plant growth.
Alternatively, aquaponic nutrient cycles can be optimized through the introduc-
tion of an anaerobic reactor to transform solid sh waste into plant-digestible
phosphorus (Goddek et al. 2016). Currently, The Plant in Chicago, USA is planning
to operate an anaerobic digester which may play a part in optimizing nutrient cycles
for crop growth. The mechanical system requirements for DRAPS and anaerobic
digestion will inuence the performance as well as the spatial layout of an
aquaponic farm.
21.5.3 End-of-Life Impacts
Materials Waste Management A theoretical advantage of CEA over open-eld
farming is the ability to control materials waste runoff, preventing leaching
(Despommier 2013; Gould and Caplow 2012). A tight envelope can play a role in
efcient materials waste management. One pathway of recycling organic waste
matter to improve building performance is the use of plant stalks for the production
of insulating biochar, although this research is in early stages (Llorach-Massana et al.
2017). Additionally, considering the incorporation of waste management compo-
nents such as a ltration bed, an anaerobic digester or a heat recovery ventilator into
the enclosure design at an early stage can close energy, nutrient, and water loops for
the farm.
Distribution Chains Packaging has been a hotspot in various farm LCAs assessing
the impact of production. It is responsible for as much as 45% of the total impact for
a tomato in Bologna, Italy, and is the largest contributor to the environmental
impacts of indoor hydroponic systems in Stockholm, Sweden (Molin and Martin
2018b; Orsini et al. 2017; Rothwell et al. 2016). Siting aquaponic farms close to
consumers can reduce the need for packaging, storage, and transport as with other
forms of urban agriculture, if local retailers and distributors collaborate with farmers
(Specht et al. 2014). Unfortunately, due to consumer acceptance, most large-scale
retailers currently require standard plastic packaging for aquaponic produce to be
sold alongside conventional brands - therefore, selecting a site close to a consumer
550 G. Proksch et al.
market for controlled environment aquaponics does not guarantee signicant
changes in the overall performance of the farm.
Reduced transportation, or food-miles, is often cited in the literature as a major
advantage of urban agriculture (Benke and Tomkins 2017; Despommier 2013;
Sanjuan-Delmás et al. 2018). However, it is important to note that the relative
contribution of shortened transportation chains varies on a case-by-case basis. In
Singapore, where nearly all food has to be imported from neighboring countries,
cutting transportation chains makes sense nancially and in terms of environmental
impact (Astee and Kishnani 2010). The same cannot be said for Spain, where the
conventional supply chain of tomatoes from farm to city is already short (Sanjuan-
Delmás et al. 2018). Cities with the longest supply chains can benet from localized
food production, but the benets of cutting transportation must be weighed against
operational and embodied impacts. In the case of Boston, the benets of reduced
transportation were entirely negated by the impact of heating and operating a
greenhouse inside the city (Goldstein 2017). Despite long conventional food supply
chains, transportation impacts were similarly insignicant in the bigger picture of
CEA performance in Stockholm (Molin and Martin 2018a).
Consumption and Diet Aquaponic farms in cities can alter urban diets, which play
a signicant role in the environmental impact of food consumption (Benis and
Ferrão 2017). Meat consumption via the conventional chain produces the largest
share of the current environmental footprint and seeking protein alternatives has the
potential for a larger impact than the widespread implementation of urban agriculture
(Goldstein 2017). Since aquaponics produces sh as well as vegetables, this poten-
tial to change protein diets on a large scale should not be ignored in larger assess-
ments of environmental performance.
21.6 Integrated Urban Aquaponics
When deliberately designed with respect to environmental impact, aquaponic farms
can become part of a resource-efcient urban food system. No aquaponic farm
operates in isolation since when crops are harvested and reach the farm gate, they
enter a larger socioeconomic food network as sh and produce is distributed to
customers. At this stage, the performance of aquaponic farms is no longer conned
to the growing system and envelope economics, marketing, education, and social
outreach are also involved. Urban aquaponic farms will need to operate as compet-
itive businesses and good neighbors to be successfully integrated into city life.
21.6.1 Economic Viability
The economic viability of aquaponic farms depends on many contextual factors
where both local conventional sh production chains and open-eld farming must be
21 Aquaponics in the Built Environment 551
matched (Stadler et al. 2017). While aquaponics requires a relatively costly initial
investment, it may outperform conventional farming during the production and
distribution phase where the design of the recirculating water system reduces
water costs, and greatly reduces the need for fertilizers, which usually comprise
between 5% and 10% of overall farm costs (Hochmuth and Hanlon 2010). However,
estimating the economic viability of aquaponic farms is particularly challenging due
to the range of dynamic factors affecting performance including the local price for
labor and energy being two examples (Goddek et al. 2015). In an economic analysis
of aquaponic farms in the Midwestern United States, labor constituted 49% of all
operational costs despite the assumption that only minimum wages would be paid. In
reality, the wide range of expertise required to operate an aquaponic system will
likely warrant higher wages in an urban farm scenario (Quagrainie et al. 2018).
Site selection and envelope design have a direct relationship to the protability of
an aquaponic farm by affecting operation efciency and how broad the potential
market can be. Aquaponic farms located in urban environments can tap into multiple
markets outside agricultural production, where many aquaponic farms offer tours,
workshops, design consulting services, and supply backyard aquaponic systems for
hobbyists. Integrating agriculture with other types of spaces within urban environ-
ments can contribute to the nancial health of aquaponic farms. The ECF aquaponic
farm is located on the work yard of the industrial landmark building Malzfabrik,
Berlin, Germany, which operates a cultural center and houses work spaces for artists
and designers.
21.6.2 Accessibility and Food Security
Urban agriculture is often cited as a strategy to provide fresh food for underserved
communities located in food deserts, yet few commercial urban farms target this
demographic, proving that commercial-scale urban agriculture can be just as exclu-
sionary as conventional supply chains (Gould and Caplow 2012; Sanyé-Mengual
et al. 2018; Thomaier et al. 2015). Aquaponic farms that use high-tech infrastructure
try to redeem their high investments by achieving premium prices in urban markets,
though aquaponics can also stem from grassroots and hobbyist applications.
Aquaponics may also have the potential to increase food security for urban residents.
This is evidenced in the lasting legacy of Growing Power, a non-prot organization
that until recently, ran an urban farm in Milwaukee, Wisconsin, USA started by Will
Allen in 1993. Many current aquaponic farmers attended Growing Powers work-
shops, in which Allen championed an aquaponic model that gives back to the
surrounding community by means of community-supported agriculture boxes and
classes. Initiated by Growing Powers educational programs, other aquaponic
non-prot organizations have taken up to the torch such as Dre Taylor with Nile
Valley Aquaponics in Kansas City, Kansas, USA. This farm aims to provide
100,000 pounds (45,400 kg) of local produce to the surrounding community in an
award-winning new campus for the expanding farm (Fig. 21.14).
552 G. Proksch et al.
21.6.3 Education and Job Training
Aquaponics can be used as an educational tool to promote systems thinking and
environmental mindfulness (Junge et al. 2014; Specht et al. 2014). In urban appli-
cations, aquaponic systems could be used to raise awareness of ecological cycles
much like existing soil-based farms (Kulak et al. 2013). The Greenhouse Project in
New York City translates this into a new approach to science education in public
schools. The Greenhouse Project aims to build 100 rooftop greenhouses on public
schools as science classrooms. These greenhouses, customized for their dual mission
of growing and learning, all include an aquaponic system. However, aquaponic
systems also require greater collaboration between existing academic disciplines in
order to move forward in this new multidisciplinary academic eld (Goddek et al.
2015). The collaboration of aquaculture and horticulture specialists, engineers,
business strategists, and built environment professionals amongst many others is
necessary to turn aquaponics into an important contributor to sustainable urban
development.
21.7 Conclusions
There is an array of criteria that contribute to the performance of each farm and their
number grows with the number of disciplines involved in this the interdisciplinary
eld of aquaponics. Of note is an earlier study that has provided a denition of
aquaponics and a classication of the types of aquaponics based on size and system
Fig. 21.14 Proposed Nile Valley Aquaponics campus (Kansas City, Kansas, USA) by HOK
Architects
21 Aquaponics in the Built Environment 553
(Palm et al. 2018). Many criteria for the analysis of the enclosure type identied in
this study stem from immediate farm context local climate, the quality of the built
environment context, energy sourcing practices, costs, market, and local regulatory
frameworks. An aquaponic greenhouse in a rural context performs differently than
one in a city, just as farms in arid climates do not share the same requirements as their
counterparts in colder areas. In general, greenhouses classied as medium-tech and
passive solar offer a lower cost, environmentally sustainable enclosure option,
currently only used by smaller aquaponic operations. However, due to their inten-
tionally limited level of technical environmental controls, they only perform well in
specic climate zones. In comparison, high-tech and rooftop greenhouses can be
technically implemented anywhere, though in extreme climate conditions they
generate high operational costs and larger environmental footprints. Recent case
studies show that indoor growing facilities can be nancially feasible, but due to
their exclusive reliance on electrical lighting, their resource use efciency and
environmental footprint are of concern. Further research is needed to establish the
relationship of specic aquaponic farms and their enclosures to existing resource
networks. This work can help connect aquaponics to research done on urban
metabolism.
Other criteria determining farm typology and performance are internal. These
include environmental control levels, crop and sh selection, aquaponic system type
and scale and enclosure type and scale. Taking on an integrated LCA approach, the
relationship between all factors have to be assessed throughout the lifespan of the
farm, from cradle to grave. Life cycle assessment of aquaponic farms must include
both building impacts and growing system impacts since there is overlap in the farm
operation phase. A series of promising strategies in heating, cooling, lighting, and
material design can improve overall farm efciency throughout the entire lifespan of
the farm. Beyond accounting for environmental impact, LCA can become a design
framework for horticulture experts, aquaculture specialists, architects, and investors.
Continuing to survey existing commercial aquaponic farms is important to
validate LCA models, identify strategies, and cataloguing aquaponic operations
emerging on a larger scale. Combining modeling with case study research on
controlled environment aquaponics has the potential to connect aquaponics to the
larger scope of urban sustainability.
Acknowledgments The authors of this study acknowledge the nancial support of the National
Science Foundation (NSF) under the umbrella of the Sustainable Urbanization Global Initiative
(SUGI) Food Water Energy Nexus and the support of all CITYFOOD project partners for providing
ideas and inspiration.
References
Ackerman K (2012) The potential for urban agriculture in New York City: growing capacity, food
security and green infrastructure report. Columbia University Urban Design Lab, New York
Alsanius BW, Khalil S, Morgenstern R (2017) Rooftop aquaponics. In: Rooftop urban agriculture,
urban agriculture. Springer, Cham, pp 103112. https://doi.org/10.1007/978-3-319-57720-3_7
554 G. Proksch et al.
Astee LY, Kishnani NT (2010) Building integrated agriculture: utilising rooftops for sustainable
food crop cultivation in Singapore. J Green Build 5:105113. https://doi.org/10.3992/jgb.5.2.
105
Benis K, Ferrão P (2017) Potential mitigation of the environmental impacts of food systems through
urban and peri-urban agriculture (UPA) a life cycle assessment approach. J Clean Prod
140:784795. https://doi.org/10.1016/j.jclepro.2016.05.176
Benis K, Ferrão P (2018) Commercial farming within the urban built environment taking stock of
an evolving eld in northern countries. Glob Food Sec 17:3037. https://doi.org/10.1016/j.gfs.
2018.03.005
Benis K, Reinhart C, Ferrão P (2017a) Development of a simulation-based decision support
workow for the implementation of building-integrated agriculture (BIA) in urban contexts. J
Clean Prod 147:589602. https://doi.org/10.1016/j.jclepro.2017.01.130
Benis K, Reinhart C, Ferrão P (2017b) Building-integrated agriculture (BIA) in urban contexts:
testing a simulation-based decision support workow. Presented at the Building Simulation
2017, San Francisco, USA, p 10. https://doi.org/10.26868/25222708.2017.479
Benke K, Tomkins B (2017) Future food-production systems: vertical farming and controlled-
environment agriculture. Sustain Sci Pract Policy 13:1326. https://doi.org/10.1080/15487733.
2017.1394054
Bregnballe J (2015) A guide to recirculation aquaculture: an introduction to the new environmen-
tally friendly and highly productive closed sh farming systems. Food and Agriculture Orga-
nization of the United Nations: Eurosh, Copenhagen
Buehler D, Junge R (2016) Global trends and current status of commercial urban rooftop farming.
Sustainability 8:1108. https://doi.org/10.3390/su8111108
Ceron-Palma I, Sanyé-Mengual E, Oliver-Solà J, Rieradevall J (2012) Barriers and opportunities
regarding the implementation of rooftop eco.greenhouses (RTEG) in mediterranean cities of
Europe. J Urban Technol 19:87103. https://doi.org/10.1080/10630732.2012.717685
Controlled Environment Agriculture (1973) A global review of greenhouse food production
(No. 89), Economic Research Service. U.S. Department of Agriculture
de Graaf PA (2012) Room for urban agriculture in Rotterdam: dening the spatial opportunities for
urban agriculture within the industrialised city. In: Sustainable food planning: evolving theory
and practice. Wageningen Academic Publishers, Wageningen, pp 533546. https://doi.org/10.
3920/978-90-8686-187-3_42
De La Salle JM, Holland M (2010) Agricultural urbanism. Green Frigate Books
Despommier D (2013) Farming up the city: the rise of urban vertical farms. Trends Biotechnol
31:388389. https://doi.org/10.1016/j.tibtech.2013.03.008
dos Santos MJPL (2016) Smart cities and urban areasaquaponics as innovative urban agriculture.
Urban For Urban Green 20:402406. https://doi.org/10.1016/j.ufug.2016.10.004
EU Aquaponics Hub (2017) COST Action FA1305, Aquaponics map (Cost FA1305), https://www.
google.com/maps/d/u/0/viewer?ll¼50.77598474809961%2C12.62131196967971&z¼4&
mid¼1bjUUbCtUfE_BCgaAf7AbmxyCpT0
Fang Y, Hu Z, Zou Y, Zhang J, Zhu Z, Zhang J, Nie L (2017) Improving nitrogen utilization
efciency of aquaponics by introducing algal-bacterial consortia. Bioresour Technol
245:358364. https://doi.org/10.1016/j.biortech.2017.08.116
Gao L-H, Qu M, Ren H-Z, Sui X-L, Chen Q-Y, Zhang Z-X (2010) Structure, function, application,
and ecological benet of a single-slope, energy-efcient solar greenhouse in China.
HortTechnology 20:626631
Goddek S (2017) Opportunities and challenges of multi-loop aquaponic systems. Wageningen
University, Wageningen
Goddek S, Delaide B, Mankasingh U, Ragnarsdottir KV, Jijakli H, Thorarinsdottir R (2015)
Challenges of sustainable and commercial Aquaponics. Sustainability 7:41994224. https://
doi.org/10.3390/su7044199
Goddek S, Schmautz Z, Scott B, Delaide B, Keesman KJ, Wuertz S, Junge R (2016) The effect of
anaerobic and aerobic sh sludge supernatant on hydroponic lettuce. Agronomy 6:37. https://
doi.org/10.3390/agronomy6020037
21 Aquaponics in the Built Environment 555
Goldstein BP (2017) Assessing the edible city: environmental implications of urban agriculture in
the Northeast United States. Technical University of Denmark, Lyngby
Goldstein B, Hauschild M, Fernández J, Birkved M (2016) Testing the environmental performance
of urban agriculture as a food supply in northern climates. J Clean Prod 135:984994. https://
doi.org/10.1016/j.jclepro.2016.07.004
Gould D, Caplow T (2012) Building-integrated agriculture: a new approach to food production. In:
Metropolitan sustainability: understanding and improving the urban environment. Woodhead
Publishing Limited, Cambridge, pp 147170
Graamans L, Baeza E, van den Dobbelsteen A, Tsafaras I, Stanghellini C (2018) Plant factories
versus greenhouses: comparison of resource use efciency. Agric Syst 160:3143. https://doi.
org/10.1016/j.agsy.2017.11.003
Hassanien RHE, Ming L (2017) Inuences of greenhouse-integrated semi-transparent photovoltaics
on microclimate and lettuce growth. Int J Agric Biol Eng 10:1122. https://doi.org/10.25165/
ijabe.v10i6.3407
He X, Qiao Y, Liu Y, Dendler L, Yin C, Martin F (2016) Environmental impact assessment of
organic and conventional tomato production in urban greenhouses of Beijing city, China. J
Clean Prod 134:251258. https://doi.org/10.1016/j.jclepro.2015.12.004
Hitaj C, Suttles S (2016) Trends in U.S. agricultures consumption and production of energy:
renewable power, shale energy, and cellulosic biomass, Economic information bulletin, no. 159.
USDA/Economic Research Service, Washington, DC
Hochmuth GJ, Hanlon EA (2010) Commercial vegetable fertilization principles 17
INAPRO - Innovative Aquaponics for Professional Applications (2018). http://inapro-project.edu
Ishii M, Sase S, Moriyama H, Okushima L, Ikeguchi A, Hayashi M, Kurata K, Kubota C, Kacira M,
Giacomelli GA (2016) Controlled environment agriculture for effective plant production sys-
tems in a semiarid greenhouse. JARQ 50:101113. https://doi.org/10.6090/jarq.50.101
Junge R, Wilhelm S, Hofstetter U (2014) Aquaponic in classrooms as a tool to promote system
thinking. In: Transmission of innovations, knowledge and practical experience into everyday
practice. Presented at the Conference VIVUS on agriculture, environmentalism, horticulture
and oristics, food production and processing and nutrition, Naklo, Slovenia, p 11
Junge R, König B, Villarroel M, Komives T, Jijakli MH (2017) Strategic points in aquaponics.
Water 9:182. https://doi.org/10.3390/w9030182
Khandaker M, Kotzen B (2018) The potential for combining living wall and vertical farming
systems with aquaponics with special emphasis on substrates. Aquac Res 49:14541468. https://
doi.org/10.1111/are.13601
König B, Junge R, Bittsanszky A, Villarroel M, Komives T (2016) On the sustainability of
aquaponics. Ecocycles 2(1):2632. https://doi.org/10.19040/ecocycles.v2i1.50
Körner O, Gutzmann E, Kledal PR (2017) A dynamic model simulating the symbiotic effects in
aquaponic systems. Acta Hortic 1170:309316. https://doi.org/10.17660/ActaHortic.2017.
1170.37
Kozai T, Niu G, Takagaki M (2015) Plant factory: an indoor vertical farming system for efcient
quality food production. Academic
Kulak M, Graves A, Chatterton J (2013) Reducing greenhouse gas emissions with urban agricul-
ture: a life cycle assessment perspective. Landsc Urban Plan 111:6878. https://doi.org/10.
1016/j.landurbplan.2012.11.007
Lastiri DR, Geelen C, Cappon HJ, Rijnaarts HHM, Baganz D, Kloas W, Karimanzira D, Keesman
KJ (2018) Model-based management strategy for resource efcient design and operation of an
aquaponic system. Aquac Eng 83:27. https://doi.org/10.1016/j.aquaeng.2018.07.001
Llorach-Massana P, Lopez-Capel E, Peña J, Rieradevall J, Montero JI, Puy N (2017) Technical
feasibility and carbon footprint of biochar co-production with tomato plant residue. Waste
Manag 67:121130. https://doi.org/10.1016/j.wasman.2017.05.021
Maucieri C, Forchino AA, Nicoletto C, Junge R, Pastres R, Sambo P, Borin M (2018) Life cycle
assessment of a micro aquaponic system for educational purposes built using recovered mate-
rial. J Clean Prod 172:31193127. https://doi.org/10.1016/j.jclepro.2017.11.097
556 G. Proksch et al.
Mohareb E, Heller M, Novak P, Goldstein B, Fonoll X, Raskin L (2017) Considerations for
reducing food system energy demand while scaling up urban agriculture. Environ Res Lett
12:125004. https://doi.org/10.1088/1748-9326/aa889b
Molin E, Martin M (2018a) Assessing the energy and environmental performance of vertical
hydroponic farming (No. C 299). ICL Swedish Environmental Research Institute, ICL Swedish
Environmental Research Institute
Molin E, Martin M (2018b) Reviewing the energy and environmental performance of vertical
farming systems in urban environments (No. C 298). ICL Swedish Environmental Research
Institute, ICL Swedish Environmental Research Institute
Monsees H, Kloas W, Wuertz S (2017) Decoupled systems on trial: eliminating bottlenecks to
improve aquaponic processes. PLoS One 12:e0183056. https://doi.org/10.1371/journal.pone.
0183056
Nadal A, Llorach-Massana P, Cuerva E, López-Capel E, Montero JI, Josa A, Rieradevall J,
Royapoor M (2017) Building-integrated rooftop greenhouses: an energy and environmental
assessment in the mediterranean context. Appl Energy 187:338351. https://doi.org/10.1016/j.
apenergy.2016.11.051
Orsini F, Dubbeling M, de Zeeuw H, Prosdocimi Gianquinto GG (2017) Rooftop urban agriculture,
Urban agriculture (springer (rm)). Springer, Cham
Palm HW, Knaus U, Appelbaum S, Goddek S, Strauch SM, Vermeulen T, Jijakli M, Kotzen B
(2018) Towards commercial aquaponics : a review of systems, designs, scales and nomencla-
ture. Aquac Int 26(3):813842. ISSN 0967-6120. https://doi.org/10.1007/s10499-018-0249-z
Pattillo DA (2017) An overview of aquaponic systems: aquaculture components (No. 20), NCRAC
Technical Bulletins. North Central Regional Aquaculture Center
Payen S, Basset-Mens C, Perret S (2015) LCA of local and imported tomato: an energy and water
trade-off. J Clean Prod 87:139148. https://doi.org/10.1016/j.jclepro.2014.10.007
Pearson LJ, Pearson L, Pearson CJ (2010) Sustainable urban agriculture: stocktake and opportuni-
ties. Int J Agric Sustain 8:719. https://doi.org/10.3763/ijas.2009.0468
Proksch G (2017) Creating urban agriculture systems: an integrated approach to design. Routledge,
New York
Quagrainie KK, Flores RMV, Kim H-J, McClain V (2018) Economic analysis of aquaponics and
hydroponics production in the U.S. Midwest. J Appl Aquac 30:114. https://doi.org/10.1080/
10454438.2017.1414009
Rothwell A, Ridoutt B, Page G, Bellotti W (2016) Environmental performance of local food: trade-
offs and implications for climate resilience in a developed city. J Clean Prod 114:420430.
https://doi.org/10.1016/j.jclepro.2015.04.096
Sanjuan-Delmás D, Llorach-Massana P, Nadal A, Ercilla-Montserrat M, Muñoz P, Montero JI,
Josa A, Gabarrell X, Rieradevall J (2018) Environmental assessment of an integrated rooftop
greenhouse for food production in cities. J Clean Prod 177:326337. https://doi.org/10.1016/j.
jclepro.2017.12.147
Sanyé-Mengual E (2015) Sustainability assessment of urban rooftop farming using an interdisci-
plinary approach. Universitat Autònoma de Barcelona, Bellaterra
Sanyé-Mengual E, Oliver-Solà J, Montero JI, Rieradevall J (2015) An environmental and economic
life cycle assessment of rooftop greenhouse (RTG) implementation in Barcelona, Spain.
Assessing new forms of urban agriculture from the greenhouse structure to the nal product
level. Int J Life Cycle Assess 20:350366. https://doi.org/10.1007/s11367-014-0836-9
Sanyé-Mengual E, Martinez-Blanco J, Finkbeiner M, Cerdà M, Camargo M, Ometto AR,
Velásquez LS, Villada G, Niza S, Pina A, Ferreira G, Oliver-Solà J, Montero JI, Rieradevall J
(2018) Urban horticulture in retail parks: environmental assessment of the potential implemen-
tation of rooftop greenhouses in European and south American cities. J Clean Prod
172:30813091. https://doi.org/10.1016/j.jclepro.2017.11.103
Simonen K (2014) Life cycle assessment. Routledge, London
Specht K, Siebert R, Hartmann I, Freisinger UB, Sawicka M, Werner A, Thomaier S, Henckel D,
Walk H, Dierich A (2014) Urban agriculture of the future: an overview of sustainability aspects
21 Aquaponics in the Built Environment 557
of food production in and on buildings. Agric Hum Values 31:3351. https://doi.org/10.1007/
s10460-013-9448-4
Stadler MM, Baganz D, Vermeulen T, Keesman KJ (2017) Circular economy and economic
viability of aquaponic systems: comparing urban, rural and peri-urban scenarios under Dutch
conditions. Acta Hortic 1176:101114. https://doi.org/10.17660/ActaHortic.2017.1176.14
Stewart ID, Oke TR (2010) Thermal differentiation of local climate zons using temperature
observations from urban and rural eld sites. Presented at the Ninth symposium on urban
environment, Keystone, CO, p 8
Suhl J, Dannehl D, Kloas W, Baganz D, Jobs S, Scheibe G, Schmidt U (2016) Advanced
aquaponics: evaluation of intensive tomato production in aquaponics vs. conventional hydro-
ponics. Agric Water Manag 178:335344. https://doi.org/10.1016/j.agwat.2016.10.013
Thomaier S, Specht K, Henckel D, Dierich A, Siebert R, Freisinger UB, Sawicka M (2015) Farming
in and on urban buildings: present practice and specic novelties of zero-acreage farming
(ZFarming). Renewable Agric Food Syst 30:4354. https://doi.org/10.1017/
S1742170514000143
Van Woensel L, Archer G, Panades-Estruch L, Vrscaj D, European Parliament, Directorate-General
for Parliamentary Research Services (2015) Ten technologies which could change our lives:
potential impacts and policy implications: in depth analysis. European Commission/EPRS
European Parliamentary Research Service, Brussels
Zabalza Bribián I, Aranda Usón A, Scarpellini S (2009) Life cycle assessment in buildings: state-of-
the-art and simplied LCA methodology as a complement for building certication. Build
Environ 44:25102520. https://doi.org/10.1016/j.buildenv.2009.05.001
Zhang H, Burr J, Zhao F (2017) A comparative life cycle assessment (LCA) of lighting technologies
for greenhouse crop production. Journal of Cleaner Production, Towards eco-efcient agricul-
ture and food systems: selected papers addressing the global challenges for food systems,
including those presented at the Conference LCA for Feeding the planet and energy for life
(68 October 2015, Stresa & Milan Expo, Italy) 140:705713. https://doi.org/10.1016/j.jclepro.
2016.01.014
Open Access This chapter is licensed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits use, sharing,
adaptation, distribution and reproduction in any medium or format, as long as you give appropriate
credit to the original author(s) and the source, provide a link to the Creative Commons licence and
indicate if changes were made.
The images or other third party material in this chapter are included in the chapter s Creative
Commons licence, unless indicated otherwise in a credit line to the material. If material is not
included in the chapters Creative Commons licence and your intended use is not permitted by
statutory regulation or exceeds the permitted use, you will need to obtain permission directly from
the copyright holder.
558 G. Proksch et al.
... Interest in aquaponics and hydroponics has surged in the past 10-15 years [31], [57]. Most aquaponics systems are small, home-based setups used by families to grow some of their food [57]. ...
... Interest in aquaponics and hydroponics has surged in the past 10-15 years [31], [57]. Most aquaponics systems are small, home-based setups used by families to grow some of their food [57]. Additionally, "hobby" hydroponics has gained popularity in recent decades [45]. ...
... Although there are a number of commercial aquaponics operations in the US, most of the respondents from the survey were not commercial operators but were using the technology to grow some of their own food and had a sense they were producing healthier food in an environmentally friendly manner. Many of the home or hobbybased aquaponics systems in the US are owner built [57], and there is large diversity in designs. Also, many species of fish are used from ornamentals to food fish. ...
Conference Paper
Full-text available
In urban farming, research and innovation are taking place at an unprecedented pace, and soilless growing technologies are emerging at different rates motivated by different objectives in various parts of the world. While the ultimate goal is local food production, adoption rates vary due to socioeconomic factors.
... Interest in aquaponics and hydroponics has proliferated in the past 10-15 years [31], [56]. Most aquaponics units are small, home-based systems used by families to grow some of their own food [57], and "hobby" hydroponics has also become popular in the last few decades [44]. Scaling up to large commercial operations in aquaponics is only recently beginning to occur [58], and there is not yet enough information to fully assess the sustainability of widespread large commercial operations [37], [53], [59]- [60]. ...
... Although there are a number of commercial aquaponics operations in the US, most of the respondents from the survey were not commercial operators but were using the technology to grow some of their own food and had a sense they were producing healthier food in an environmentally friendly manner. Many of the home or hobbybased aquaponics systems in the US are owner built [57], and there is large diversity in designs. Also, many species of fish are used ranging from ornamental species to edible fish. ...
... In seeking alternatives, aquaponics has emerged as a novel approach to overcoming numerous sustainability challenges across the agricultural sector (Goddek et al. 2019;Yep and Zheng 2019), connecting recirculating aquaculture systems (RAS) with hydroponic horticulture. In this way, aquaponics has gained momentum as an agri-aquacultural innovation that maximises yield under limited resource input (Obirikorang et al. 2021), mitigates soil erosion and carbon emissions (Yang and Kim 2020), facilitates cultivation across peri-urban and urban environments (David et al. 2022;Wizra and Nazir 2021); and supports diversified socio-economic opportunities (Proksch et al. 2019). ...
Article
Full-text available
Aquaponics (a sub-field of integrated agri-aquacultural practices (IAAS)) has emerged as a novel approach to combat global food security, reduce soil erosion and nutrient loss, and mitigate agronomic greenhouse gas (GHG) emissions. However, little remains known of potential consumer markets. Despite recent research throughout Europe, Central America, Australia, and the Middle East, this work represents the first large-scale evaluation of UK consumer understanding, assessment, and willingness to pay (WTP) for aquaponic products. Following analysis of 588 survey responses, we identify environmental awareness and green consumption, recognition of common UK eco-labels and sector-specific certification schemes, and consumer perceptions of aquaponics compared to conventional, locally sourced, and organic food production. Initially, 44% of survey respondents were familiar with aquaponics, with familiarity positively influenced by age and level of education. After presenting a definition of aquaponics (detailing its use and commonly cited socio-environmental benefits), consumer perceptions were mixed, with respondents broadly favourable to the practice despite uncertainty. Over 43% of consumers were willing to pay an associated price premium for aquaponic produce (valued, on average, as a 23% price increase over conventional alternatives). This willingness to pay was statistically in line with the organic market premiums and independent of prior familiarity with aquaponics as a food production system. These findings suggest a sizable consumer market for aquaponic produce and public interest in its sustainability benefits. Tailored marketing strategies could position aquaponic produce competitively alongside organic and environmentally friendly alternatives (irrespective of certification/eco-labelling), ensuring the long-term economic viability of the emerging aquaponics industry.
... 73 Additionally, using natural, biological filtration methods contributes to a healthier aquatic environment. 74 It proves to be a highly efficient method for cultivating food, utilizing only 10% of the water required in traditional farming and eliminating the need for chemical fertilizers. 75 The Sundarbans' rich potential for fish farming offers an opportunity to integrate aquaponics systems that are in a rithm with the mangrove ecosystem. ...
Article
Full-text available
Aquaponics, an innovative and symbiotic approach to agricultural practices, has gained increasing attention as a potential pathway to enhance the sustainability of ‘Aqua-Agri’ farming in India. This review comprehensively explores the current state of aquaponics in the Indian context, examining its overview, suitability, challenges, and potentiality. The analysis encompasses the ecological dynamics of aquaponic systems, emphasizing the efficient utilization of resources in Indian context, minimal environmental impact, and the potential for increased yields in both fish and plant production. Additionally, it explores successful case studies, showcasing the viability and adaptability of aquaponics across diverse regions in India. The review concludes by outlining future research directions and policy recommendations to foster the widespread adoption of aquaponics as a transformative and sustainable method within the aquaculture sector in India.
... Furthermore, the idea of growing food locally is being discussed as an important part of food production for cities (Joyce et al., 2019a;Skar et al., 2020). Soilless growing, often in controlled environments, is becoming more common as part of urban agriculture (Proksch et al., 2019), particularly in developed countries. ...
Thesis
Full-text available
All known aquaponics systems in Nepal were described and owners, who were willng, were interviewed to characterize the status of the technology in the Nepali context and to identify limiting factors to expansion. A major limiting factor was high cost of commercial fish food for many operators. A controlled experiment evaluated the effects on plant and fish growth of less expensive, alternate diets compared to commercial fish food.
... Despite the promotion of the benefits of aquaponic systems in urban environments [39], it was surprising to notice that aquaponic systems were very evenly distributed among urban (30.4%, n = 14), peri-urban (34.8%, n = 16), and rural (34.8%, n = 16) areas. Different markets apply to these different zones, suggesting a high degree of variability in the design and management of aquaponic systems. ...
Article
Full-text available
The European aquaponic sector started to develop and professionalize in the early 2010′s. This development and the subsequent challenges faced by early practitioners were investigated in various publications between 2015 and 2020. Although most of these studies were focused on educational and research institutions, only a few included commercial entities. The present survey is aimed at defining and assessing the recent evolution of the European aquaponic activities in professional structures. One hundred and forty professional aquaponic entities (non-profit organization, educational, and commercial) having an aquaponic system with more than 1 m3 of water in their recirculating aquaculture systems were identified in Europe. Among them, 46 responded to a survey about the technical and business aspects of their structures. In comparison to previous surveys, a much higher number of entities had larger systems (up to 14,000 m2), with higher yields (up to 20 t of fish or vegetables per year), whereas 59% of them declared making profits. This revealed a clear expansion and professionalization of the sector, which was found to be highly diversified, with systems varying greatly in size, design, and technology. Business models and activities were generally diverse, and included a combination of production, education, and/or services. Most entities also combined different customer segments. At the time of the survey, the aquaponic sector was still struggling to find its economic viability, as the business model of most entities did not only rely on fish and vegetable sales, but also largely relied on free labor through volunteers or internships. Acquiring knowledge as well as optimizing production and business models were perceived as the main challenges for the steady growth of the sector. Consequently, there is a clear need to increase training, to continue the research and development work, and create public support systems for aquaponics farms to further improve and expand the commercialization of aquaponics in Europe.
Chapter
The generalized expansion of urbanization and population requires the implementation of sustainable practices in cities, particularly in developing nations more vulnerable to climate change impacts. Blue-green infrastructures can be viable solutions to climate and sustainability emergencies in the built environment. In this context, urban areas possess the opportunity to create climate change-resilient agricultural systems in order to meet the “No Poverty” (SDG 1) and “Zero Hunger” (SDG 2) goals included in the United Nations (UN) Sustainable Development Goals (SDGs). Consequently, with 70% of the population residing in urban areas, food systems can close the gap between production and consumption to ensure local food security. The substantial growth of cities in Asia, South America, and Africa renders localized urban agriculture essential for feeding its inhabitants. As the Food and Agriculture Organization (FAO) indicates, 6,000 tons of food are imported daily to feed cities with more than 20 million residents, such as Sao Paolo or Mexico City. Food chains and imports could be drastically mitigated by utilizing existing urban surfaces (roofs, facades, and ground areas) to produce crops. For this reason, there is a rising demand for research to assist urban planners and governments in strategizing local agriculture production. This chapter addresses food security in developing cities by introducing a sunlight-based computational approach for designating the agricultural potential of three-dimensional urban surfaces according to crop-centric environmental suitability. Building-integrated agriculture (BIA) can deliver crops throughout the entire year, minimizing the externalities that endanger food production, such as climate variations (droughts and floods) and climate-induced pests (from human and soil pathogens). Critics of high-tech indoor developments in hydroponics, aeroponics, and aquaponics argue that these systems are energy-intensive. In response, hybrid lighting systems offer alternative solutions that can efficiently reduce energy requirements by integrating sunlight data analysis. Blending sunlight to optimize lighting can have remarkable energy savings of up to 70% in developing nations with constricted energy infrastructures. Therefore, the availability of an appropriate amount of solar radiation on three-dimensional surfaces is a critical factor in selecting BIA locations.
Chapter
In recent years, the efficient use of water resources has become a critical challenge in agriculture due to water scarcity. Scientists are actively researching various aspects of irrigation, including optimizing water use, improving irrigation techniques, and enhancing crop productivity. However, there exists a realistic gap between scientific knowledge and its practical implementation in the fields. This chapter explores the concept of actionable science for irrigation, highlighting the barriers that prevent research from being effectively translated into actionable strategies. The cutting edge research includes crop water requirements, irrigation scheduling, precision irrigation technologies, and water management strategies. Despite the progress made in scientific understanding, the research often lacks direct applicability due to factors such as limited stakeholder engagement, inadequate dissemination of research findings, and the complexity of translating scientific knowledge into practical guidelines. To bridge this gap, it is essential to foster collaboration between scientists, farmers, and policymakers, promote knowledge exchange platforms, and develop user-friendly decision-support tools that provide actionable recommendations for irrigation management. The chapter highlights the importance of stakeholder engagement, effective knowledge transfer, and the development of user-friendly tools to enhance the practicality and implementation of scientific research. Readers will gain an understanding of the expectations and responsibilities of scientists, farmers, and policymakers in adopting actionable science for sustainable and efficient irrigation practices, ultimately leading to improved water resource management and agricultural productivity.
Book
Full-text available
Creating Urban Agriculture Systems offers you background, expertise, and inspiration for designing with urban agriculture. It shows you how to grow food in buildings and cities, operate growing systems, and integrate them with natural cycles and existing infrastructures. It teaches the essential environmental inputs and operational strategies of urban farms, and inspires community and design strategies for innovative operations and sustainable urban environments that produce fresh, local food. Over 70 projects and sixteen in-depth case studies of productive, integrated systems, located in North America, Europe, and Asia are organized by their emphasis on nutrient, water, and energy management, farm operation, community integration, and design approaches so that you can see innovative strategies in action. Interviews with leading architecture firms including WORKac, Kiss + Cathcart, Weber Thompson, CJ Lim/Studio 8, and SOA Architects highlight the challenges and rewards you face when creating urban agriculture systems. Catalogs of growing and building systems, a glossary, bibliography, and abstracts will help you find information fast.
Technical Report
Full-text available
The global population is increasing rapidly, and the amount of people living in urban areas are expected to almost double within 30 years. With a rising population, the demand for food and pressure on arable land is also increasing. Currently, about 26 % of the greenhouse gases emitted from Sweden come from agricultural activities, and with an increasing population, it is essential to aim to reduce the emissions from food supply. Vertical farming has seen increasing popularity as a way to reduce the need for arable land and grow crops where they are to be consumed. When farming indoors in a closed environment, the plants are protected from the weather, insects and pests. There are no leakages of nutrients in closed systems and the amount of water used is very limited in comparison to conventional farming. However, artificial lighting is needed in order for the crops to grow. Additionally, vertical farming is capital intensive and requires technical knowledge to be able to make use of the new techniques and equipment available. In this study, the sustainability of the vertical farming system at Grönska Stadsodling, hereafter referred to as Grönska, has been evaluated. Grönska is located in southern Stockholm and produces primarily basil in pots that are sold to retailers around the city using vertical-hydroponic techniques. The energy use and environmental impacts for the production of herbs (basil) were assessed using life cycle assessment (LCA) from a cradle-to-gate perspective. This included the materials (e.g. soil, fertilizers) and energy consumption used for growing basil plants. The use (consumption), waste management and transportation to and from the company were not included in this study. The results illustrated a large share of energy used for the manufacturing of gardening soil, which also resulted in the second largest environmental impact. The largest source of environmental impacts was the energy consumed for lighting, despite the use of LED lighting. There are possibilities to reduce these impacts by e.g. installing solar panels and optimizing the output of LEDs for the plant production. Furthermore, energy could be saved by changing the growing material, for something with less environmental impacts e.g. coir pith or by recycling the soil used. While extended transportation distances of food is one of the main arguments for urban agriculture, energy consumption and environmental impacts for transportation were found to be a minor part of the energy use and environmental impacts. Finally, the socio-economic implications of urban farming should be taken into account when reviewing sustainability aspects. This study only reviewed energy and environmental impacts, but the socio-economic benefits and resilience for the local community are important to highlight. Please also see the article produced from this report at: https://www.researchgate.net/publication/334785876_Environmental_Assessment_of_an_Urban_Vertical_Hydroponic_Farming_System_in_Sweden
Article
Full-text available
Aquaponics is rapidly developing as the need for sustainable food production increases and freshwater and phosphorous reserves shrink. Starting from small-scale operations, aquaponics is at the brink of commercialization, attracting investment. Arising from integrated freshwater aquaculture, a variety of methods and system designs has developed that focus either on fish or plant production. Public interest in aquaponics has increased dramatically in recent years, in line with the trend towards more integrated value chains, greater productivity and less harmful environmental impact compared to other production systems. New business models are opening up, with new customers and markets, and with this expansion comes the potential for confusion, misunderstanding and deception. New stakeholders require guidelines and detail concerning the different system designs and their potentials. We provide a definitive definition of aquaponics, where the majority (> 50%) of nutrients sustaining the optimal plant growth derives from waste originating from feeding aquatic organisms, classify the available integrated aquaculture and aquaponics (open, domestic, demonstration, commercial) systems and designs, distinguish four different scales of production (≤ 50, > 50–≤ 100 m2, > 100–≤ 500 m2, > 500 m2) and present a definite nomenclature for aquaponics and aquaponic farming allowing distinctions between the technologies that are in use. This enables authorities, customers, producers and all other stakeholders to distinguish between the various systems, to better understand their potentials and constraints and to set priorities for business and regulations in order to transition RAS or already integrated aquaculture into commercial aquaponic systems.
Article
Full-text available
Aquaponics is a method of food production, growing fish and vegetables in a recirculating aquaculture system. Aquaponics uses the water from the fish to feed the plants in a totally natural way and like hydroponics, aquaponics is considered to be more sustainable as more plants can be grown per square metre compared to normal agriculture. However, as is the case with normal agriculture, in aquaponics plants are grown within horizontally. In aquaponics, using the UVI system, the ratio between fish tanks:filters:plant tanks is 2:1:5 which means that the plant tanks are occupying close to half of the production space. In order to reduce the spatial requirement for plants, which would make production even more sustainable, this research investigates aspects of combining living wall and vertical farming technologies in aquaponics. It is considered that by growing the plants vertically less space would be required. In this research living wall system is investigated but the main focus is on the potentials of using various inert substrates in the living wall systems for vertical aquaponics. The results showed that a pot system performs better in terms of management of the systems. With regard to substrates, horticultural grade coconut fibre and horticultural grade mineral wool outperformed other substrates.
Technical Report
This publication covers the aquaculture components of aquaponic systems with relative comparisons of materials, equipment, and methods commonly used.
Article
Aquaponics is a technique that combines aquaculture with hydroponics, i.e. growing aquatic species and soilless plants in a single system. Commercial aquaponics is still in development. The main challenge consists in balancing the conditions required for the growth of multiple species, leading to dynamic a system with high complexity. Mathematical models improve our understanding of the complex dynamics in aquaponics, and thus support the development of efficient systems. We developed a water and nutrient management strategy for the production of Nile tilapia (Oreochromis niloticus) and tomato (Solanum lycopersicum) in an existing INAPRO aquaponic demonstration system in Abtshagen, Germany. This management strategy aims for improved water and nutrient efficiency. For this purpose, we developed a system-level mathematical model and simulation. In our simulations, we found that the existing configuration and water management of the Abtshagen aquaponic system results in an excessive amount of water discharged from the RAS. Therefore, sending more nutrient-rich water from fish to plants can help reducing water and fertilizer consumption. However, this water transfer may lead to excess concentrations of some nutrients, which could stress fish, plants or both. For the Abtshagen system, our simulations predicted excess concentrations of total suspended solids (TSS) for the fish, and sodium (Na⁺) and ammonium nitrogen (NH4+-N) for the plants. Furthermore, our simulations predicted excess calcium (Ca²⁺) and magnesium (Mg²⁺) for plants, due to the use of local fresh water with relatively high concentrations of those ions. Based on our simulations, we developed an improved management strategy that achieves a balance between resource efficiency and water quality conditions. This management strategy prevents excess levels of TSS for fish, and Na⁺ and NH4+-N for plants. Under the improved management strategy, simulated water requirements (263 L/kg fish and 22 L/kg tomato) were similar to current commercial RAS and greenhouse horticulture. Simulated fertilizer requirements for plants of N, Ca and Mg (52, 46 and 9 mg/kg tomato, respectively) were one order of magnitude lower than in high efficient commercial closed greenhouse production.
Article
Vertical farming is emerging as an effective measure to grow food in buildings and can increase food production in urban areas in a more sustainable manner. This study presents a comprehensive environmental assessment of food production in an integrated rooftop greenhouse (i-RTG) – an innovative vertical farm consisting of a rooftop greenhouse connected to a building – and considers rainwater, residual heat (energy), residual air (CO2) and food from an industrial ecology perspective. This synergistic connection preserves resources and improves conditions in the greenhouse and the building. The goal of the study is to show the feasibility of the system and to calculate the environmental impacts from its whole life cycle, from infrastructure to end of life, by comparing these impacts with those of conventional production. The results show that the system is feasible and produced 30.2 kg/m² of tomato over 15.5 months. The synergy with the building allows the cultivation of winter-fall crops without supplying heating and maintained an average temperature 8 °C higher than that outdoors. Moreover, rainwater was used to irrigate the crops, reducing consumption from the water supply network by 80–90%. The environmental assessment showed that the operation of the i-RTG has more impacts than the infrastructure (structure of the greenhouse, rainwater harvesting system and equipment) due to the use of fertilisers, which account for 25% of the impacts in four of the six impact categories studied. Regarding the infrastructure, the greenhouse structure and rainwater harvesting system of the building have substantial environmental impacts (over 30% in four of the six impact categories). Comparison with a conventional greenhouse demonstrates that the i-RTG has a better environmental performance, showing between 50 and 75% lower impacts in five of the six impact categories (for instance, 0.58 kg of CO2 equivalent per kg of tomato vs. 1.7 kg), mainly due to the reduced packaging and transport requirements. From this study, it was concluded that optimisation of the amount of infrastructure material and management of the operation could lead to even better environmental performance in future i-RTG projects.
Article
This paper examined the profitability of aquaponics in the US Midwest. Three sources of data were considered for the study: (1) three active aquaponics farms, (2) university greenhouse experiment, and (3) published research. The first analysis compares the economics of aquaponics and hydroponics systems under similar operations. Results suggest that the aquaponics system requires higher investment and operating cost but has lower production of vegetables compared with the hydroponics system. However, if aquaponics vegetable production is managed as organic production, and the produce sold at 20% premium price, aquaponics becomes profitable. The second analysis constructed three different representative farm sizes of aquaponics production of basil and tilapia - small, medium and large. The production of basil provides better economic returns than the fish. All farm sizes are feasible when basil price is above $10.00 per kg. The larger farm has the best results, because of lower cost of production.