![Scheme of the annual heat demand and the synergetic combination of solar thermal and biomass for DH, [8, 9]](https://www.researchgate.net/profile/Jakob-Worm-2/publication/333638709/figure/fig1/AS:766595177672705@1559781941815/Scheme-of-the-annual-heat-demand-and-the-synergetic-combination-of-solar-thermal-and_Q320.jpg)
Content uploaded by Jakob Worm
Author content
All content in this area was uploaded by Jakob Worm on Jun 10, 2019
Content may be subject to copyright.
Available via license: CC BY-NC-ND
Content may be subject to copyright.
TRANSITION TOWARDS A SUSTAINABLE HEATING AND COOLING SECTOR
- CASE STUDY OF SOUTHEAST EUROPEAN COUNTRIES
Dominik RUTZ1, Jakob WORM2, Christian DOCZEKAL3, Anes KAZAGIC4*, Neven DUIC5,
Natasa MARKOVSKA6, Ilija BATAS BJELIC7, Rok SUNKO8, Dino TRESNJO4, Ajla
MERZIC4, Borna DORACIC5, Vladimir GJORGIEVSKI6, Rainer JANSSEN1, Elma
REDZIC4, Richard ZWEILER3, Tomislav PUKSEC5, Blaž SUNKO8, Nikola RAJAKOVIC7
1Unit Bioenergy & Bioeconomy, WIP Renewable Energies, Sylvensteinstr. 2, D - 81369 Munich,
Germany,
2PlanEnergi, Aarhus, Denmark,
3Güssing Energy Technologies GmbH, Güssing, Austria,
4JP Elektroprivreda BiH, Sarajevo, Bosnia and Herzegovina,
5University of Zagreb, Zagreb, Croatia,
6International Centre for Sustainable Development of Energy, Water and Environment Systems -
Affiliate Skopje, Macedonia,
7School of Electrical Engineering, Belgrade, Serbia,
8Skupina fabrika d.o.o., Ljutomer, Slovenia
*Corresponding author; E-mail: a.kazagic@epbih.ba
Many traditional heating systems which are based on fossils face challenges
such as lack of investment or unfavorable price regulations, low technical
performance, environmental impacts and negative consumer perceptions.
The CoolHeating project which is, funded by the EU’s Horizon 2020
programme and presented in this paper promotes the implementation of
small modular renewable heating and cooling grids for communities in
South-Eastern Europe. Core project activities bincluded measures to
stimulate the interest of communities and citizens to set-up renewable
district heating systems in 5 target communities in Slovenia, Croatia, Bosnia
and Herzegovina, Serbia and Macedonia up to the investment stage.
Single criteria and multi-criteria assessment approaches, considering
economic, environmental and social indicators of the targeted projects, have
been applied in this work in order to investigate opportunities for the
sustainable transition of the heating and cooling sectors of the target
communities of Southeast Europe. Both approaches confirm the feasibilities
of the transition from traditional to renewable energy-based heating systems
for each target community in the countries of South-Eastern Europe. After
simulation and replication of the results, the sustainability analysis
indicatively shows that the transitions from traditional fossil-based, poor-
maintained and difficult-to-manage heating systems towards renewable
district heating and cooling (DHC) systems in Southeast Europe are
sustainable solutions. Having in mind the modularity of such systems, those
solutions can be replicated in other Southeast European cities and other
countries.
Key words: Heating, District heating systems, Modular renewable heating
grids, Sustainability assessment
1. Introduction
The heating and cooling sector is only slowly becoming cleaner, as heat supply from fossil fuels
is still very high, both in the world (90%) and in the European Union (70%). This is due to the fact
that fossil fuels are still the main energy source for both CHP and boiler plants, [1]. In Europe, the
heating and cooling demand accounts for around 50% of the EU’s final energy consumption. In order
to reduce carbon dioxide emissions in the heating/cooling sector, new non-fossil heat sources must
replace the current fossil-based plants. District heating (DH) as an efficient solution for heat supply
and distribution can play a major part in meeting decarbonization targets. According to the EU
Strategy on Heating and Cooling (2016), the contribution of DH in the EU accounts for 9% and is
mainly driven by fossil fuels such as gas and coal, [2]. District and cooling heating networks present a
high potential for the transition of the heat/cooling sector, both technically and organizationally, [3].
They allow the integration of renewable energies and thus can improve the overall energy efficiency
and facilitate sector coupling (coupling between heating, electricity and mobility), [4,5]. In order to
use this potential, many DH networks must first upgrade the existing distribution system, including the
substations and consumer connections: reaching lower leakage rates and heat losses, reducing
operation temperatures, adapting piping dimensions and hydraulics, introducing modern IT-based
management systems and options for user control. This makes the heat distribution more efficient, but
also improves the efficiency of the heat generation, hence, saving the primary energy. Moreover, it
allows the integration of renewable energies and waste heat. In a further step, efficiency measures can
be implemented on the generation side and the share of renewable and waste heat can be introduced
and increased gradually. This must go hand-in-hand with predictions of future heat demand as well as
with efficiency measures on the end use of heat, [6].
Small modular district heating and cooling (DHC) grids have several benefits. They can
contribute to increase the local economy due to local value chains of local biomass supply. Local
employment can be enhanced as well as security of supply. The comfort for the connected household
can be increased as only the heat exchanger is needed in the basement of the buildings and no fuel
purchase has to be organized. Small modular DHC grids can be fed by different heat sources,
including from solar collectors, biomass systems, heat pumps and from surplus heat sources (e.g. heat
that is not yet used from industrial processes or biogas plants). Especially the combination of solar
heating and biomass heating (Figure 1) is a very promising strategy for smaller rural communities due
to its contribution to security of supply, price stability, local economic development, local
employment, etc., [7-9]. On the one hand, solar heating requires no fuel and on the other hand biomass
heating can store energy and release it during winter when there is less solar heat available. Thereby,
heat storage (buffer tanks for short-term storage and seasonal tanks/basins for long-term storage) needs
to be integrated. With increasing shares of fluctuating renewable electricity production (PV, wind), the
Power-to-Heat conversion through heat pumps can furthermore help to balance the power grid. If the
planning process is done in a sustainable way, small modular DHC grids have the advantage, that at
the beginning only part of the system can be realized, and additional heat sources and consumers can
be added later. This modularity requires well planning and appropriate dimensioning of the equipment
(e.g. pipes). It reduces the initial demand for investment and can grow steadily, [7-9].
Figure 1. Scheme of the annual heat demand and the synergetic combination of solar thermal
and biomass for DH, [8, 9]
1.1. State of the Art
Key issue concerning DH nowadays is the integration of renewables and to show that such
district systems are feasible and sustainable solutions. Some of the recent studies focus on solar
assisted DH systems, for example a study of cost-efficient solutions for integrating solar heating in an
existing local DH system in Finland, reported in [10]. Therein centralized and distributed solar
collectors and the effects of reducing supply temperature were investigated. It was found that
centralized collector systems can provide cost savings from 7 to 21%. Some other investigations
involving solar heating and cooling are reported in [11] and [12] with focus on the integration and
optimization of solar thermal system in existing co-generation-based DH systems. On the other hand,
biomass DH systems are a promising way to increase thermal efficiency in rural areas and some recent
research showed such systems. In [13], authors reported on possible implementing biomass DH
facilities in 499 rural municipalities with a population above 1,500 inhabitants in the continental
region of Spain. Results show a potential for 154 biomass DH systems with an internal rate of return
above 5%, and 31 systems above 10%. On the other hand, only three DH systems are classified as
non-profitable. The massive implementation of these systems in the region under study reduce CO2
emissions from fossil fuels in 5.4 million tons per year and would imply and important impulse to
local economy. In [14], the development of a biomass combined heat and power station by smart
energy system in Jelgava is reported. The scenarios were compared via technological, economic and
bioeconomic indicators and evaluated for their restrictions for limiting long-term sustainable
development. It is concluded that bioeconomic development scenarios can support sustainability of the
DH systems. The cold deliveries from district cooling systems are much smaller than heat deliveries
from DH systems, [1]. Some recent studies on cooling concentrate on system simulation and
parametric study of the demonstration aiming to reduce electricity consumption, improve thermal
COP’s and capacity of the system, as reported in [15]. In [16] DH systems in Lithuania have been
analyzed through a sustainable energy development promoting tool for the eco-labelling scheme of
DH and cooling systems. This was based on measured energy and environmental performance data of
the DH and cooling system. Finally, in [17], various heat generation technologies were examined in a
multi-criteria sustainability assessment frame of seven attributes which were evaluated based on a
choice experiment (CE) survey.
However, it was found that none of these studies dealt with a sustainability assessment for the
transition of the heating and cooling sector, only selected assessments were done. For example, several
studies [10, 11, 12] deal with the costs savings of specific heating applications, while work [13]
estimated total CO2 emission savings for the considered group of projects in Spain. Work [14] defined
indicators and analyzed/discussed them in context of sustainability improvements, and other studies
mainly focused on overcoming technical difficulties and limitations. While [16] deal with DH sector in
Lithuania through a sustainable energy development promoting tool, [17] performed a multicriteria
sustainability assessment of different heat generation technologies in general. So, there is no
sustainability assessment applied in the field of transition of heating-cooling sector nor reliable
information about sustainability of the sector transition reported in literature so far.
1.2. Objectives
This paper investigates the sustainability of the transition of heating and cooling sectors from
traditional fossil-based solutions to renewable heating-cooling solutions. It provides a methodology for
such an assessment. This is applied to 5 target communities in the south-eastern Europe region:
Slovenia, Croatia, Bosnia and Herzegovina, Serbia, and Macedonia. Space heating in the cold season
and hot water is dominated on the European level and especially in south-eastern Europe with its
strong winters and hot summers, by the use of fossil fuels (heating oil, natural gas, coal), wood, and
grey electricity. Heating systems, either as individual boilers and systems, or as DH systems, are often
old, inefficient and with high emissions. On the other hand, efficient and renewable heating-cooling
technologies are commercially available and used in many cases, but with a very small market share
compared to the traditional systems as described above. This applies especially to South Eastern
European countries. The hypothesis is that this situation is due to the following reasons:
- South-eastern Europe is economically weaker than central Europe. Consumers have less money
available to pay for the generally higher initial investment costs of clean and modern heating
technologies.
- Low prices of fossil fuels and electricity due to subsidies make renewable heating and cooling
less attractive than in central Europe.
- The political support to change the current situation is very limited.
- Low regulatory requirements (emission standards) on air polluting installations.
These challenges are addressed by the coherent and consistent methodology of the paper by
which the heating sectors of traditional fossil based and low-economy regions, such as South-Eastern
Europe, can be transferred into a more sustainable one. For the large market penetration, the above
listed barriers need to be reduced. Several tools and methods were used to epistemologically analyze
the requirements for the implementation of renewable heating and cooling systems as a function of the
sustainable heating sector transition.
2. Materials and methods
The scope of the paper is the concept development for renewable DH system in selected
municipalities of South Eastern Europe as well as the sustainability assessment of the transition from
traditional fossil-based concepts to renewable concepts in the heating sector.
2.1. System under consideration – heating and cooling sector of Southeast Europe
In southeastern European countries, DH has not been seen as the technology to rely on. Many
existing buildings have been heated by heating oil, gas or coal and accordingly not been furnished with
water based central heating systems. The introduction of DH is not just a conversion of the heat
source, but also requires a significant investment to be carried by the homeowners. The public
perception of DH as a common, public utility also pays a role. The willingness to rely on a public
utility for heating may be quite different from how the systems are perceived in the western and
northern European countries and in the southern parts of Europe. The main technical characteristics
and difficulties of DH systems in southeastern Europe are:
- Pipes are often poorly insulated steel pipes in concrete ducts, whereas renovated areas are often
equipped with pre-insulated pipes.
- Systems were often designed for a fixed flow and for the use of ejector pumps. The original
design may have been for 150/70 °C, but modern systems could be operated at much lower
temperatures. The systems often struggle with thermal and hydraulic imbalances, fouling of heat
exchangers and water leakages.
- New DH in areas without a long tradition of DH often use industrial surplus heat (waste heat).
Here, systems are similar to the ones of central Europe, but with less focus on energy efficiency.
- Several new DH systems are installed in various countries of southeastern Europe which are
mainly based on renewable energies (e.g. solar thermal or biomass). A new approach for some of
these systems is to facilitate sector coupling (heat, power, transport). Many of the renewable-
energy-based DH systems are smaller scale systems.
Renewable energy policies in most the an countries mainly focus on the electricity market,
whereas policies for renewable heating and cooling are usually much weaker. Therefore, it is
important to support and promote renewable heating and cooling concepts. Heating, cooling and
electricity systems can support each other to realize the energy transition and to decarbonize in
southeastern Europe.
2.2. Concept of modular DH and cooling projects in Southeast Europe
Within the CoolHeating project, concepts for seven projects in the five target countries were
developed in order to supply them in total with 202 GWh/a heat and cold from renewable energies and
to supply them only in selected cases by fossil peak load boilers. Core activities, besides techno-
economical assessments, included measures to stimulate the interest of communities and citizens to
set-up renewable DH systems as well as the capacity building about financing and business models.
This initiated several new small renewable DH and cooling grids in the 5 target countries (Error!
Reference source not found. up to the investment stage. In order to develop the concepts, surveys
about the heat demand were made and options were discussed with the local stakeholders. The
following chapters briefly summarize the concepts developed within the CoolHeating project, see
website (www.coolheating.eu).
Figure 2. Concept of small modular renewable heating & cooling grids (left) in 5 target cities of
Souteast Europe (right: light blue, red points), [2, 3, 4]
2.3. Modelling and optimization
A demand forecast was made, the capacities of the production units were determined, and the
optimization of the operating mode was analyzed for each of the seven projects by the specialized
software EnergyPRO, as shown in Figure 3. It is a modelling software used primarily in relation to DH
projects. It was used to carry out an integrated detailed technical and financial analysis of both existing
and new energy projects. The software was used to plan the optimal production for the energy plant
for a whole year. The period for the optimization was calculated per hour throughout the year with a
detailed production plan. Inputs for the optimization were typically parameters such as content of
stored energy at the beginning of the optimization period, expected energy demands within the period
as well as all operating expenses. Calculations and optimization of the capacities (type and installed
power in MW) and production (heat energy generation in MWh) were based on inputs for all units,
climate conditions, connection rates for private and collective housing facilities, prices of all energy
sources, energy efficiency performances of the facilities, temperature levels of DH systems, heat loss
assumptions in the grid, operating times and so on. The software can optimize the operation every
hour based on operational costs such as maintenance costs, fuel costs, electricity prices, taxes,
subsidies, etc. The objective was to analyze the cheapest solutions for heat supply. When the operating
costs are calculated for a scenario, investments and capital costs can be calculated so that the
economically optimal solution can be found.
Figure 3. Scheme of heating and cooling production units and consumers calculated in
EnergyPRO, example of CoolHeating project Karposh
2.4. Sustainability assessment methods used
Sustainability assessment can be used for analyzing the feasibility and sustainability of RES
scenarios (options) and has been applied in [18], [19] and [20] to support the power plant selection
between considered options as function of the highest general index of sustainability. A power utility
generation portfolio optimization model in terms of its sustainability as function of specific targets on
RES share in 2030, including comparative analyses between Single criteria analysis (SCA) and
Multicriteria sustainability assessment (MSA), has been recently proposed in [21].
A similar approach of combined SCA and MSA is used in this paper. Therefore, a set of
economic and environmental indicators were defined as shown below.
- Investment (capital expenditure) – EcCAPEX (EUR/MWh)
- Fuel costs (operation expenditure) – EcOPEX (EUR/MWh).
- CO2 indicator (tonnes of CO2 emitted per MWh of produced heat energy) – EnCO2 (tCO2/MWh)
- SO2 indicator (tonnes of SO2 emitted per MWh of produced heat energy) – EnSO2 (tSO2/MWh)
- NOx indicator (tonnes of NOx emitted per MWh of produced heat energy) – EnNOx
(tNOx/MWh)
- PM indicator ((tonnes of particle matter emitted per MWh of produced heat energy) – EnPM
(tPM/MWh)
Selected economic and environmental indicators are typically used when considering a heating
system, due to their high-effecting influence on sustainability of such a system. The most important
economic indicators for this analysis, besides the Investment indicator (EcCAPEX), is the Indicator of
fuel costs (EcOPEX). This is taking into account that fuel costs are the most influencing factor by far,
among the fixed and variable O&M costs. The social aspect is analyzed by non-valuable indicators,
i.e. Increase in employment, Local income generation, or Region development. Social indicators are
evaluated for two considered cases of each target community in order to support sustainability analysis
based on environmental and economic indicators.
Economic and Environmental Sustainability Indicators (SI) are calculated for two options of
each target community on a real-base quantification of parameters (costs, emissions) within a period of
20 years (estimated Life Time of the project), divided by heat production in MWh in the life time of
20 years:
- Option 1 – Reference case – business as usual (doing nothing).
- Option 2 – CoolHeating concept – new case (renewable DH grid).
For each case study, a simple comparison of the indicators of Option 1 and Option 2 was made.
This approach is based on SCA. Then, all indicators are normalized and aggregated into a General
index of sustainability, by assigning weighting factors to each indicator. Weighting factors (rate of
influence) of each sustainability indicator are given by the authors as experts in the field, based on
their research and professional experience. Then preference of sustainability is determined by simple
comparison of the General index of sustainability for two options (scenarios) of each target
communities. In that way MSA is applied.
3. Results and discussion
Within this chapter, the main characteristics of the conceptualized seven DHC systems
considered throughout the CoolHeating project in the five target countries are presented. Results are
presented and discussed and integrated into a sustainability assessment.
3.1. Technical concepts and parameters of the projects
An overview of the technical concepts, optimized by EnergyPro, is given in Table 1.
The rural settlement of Cven in Slovenia has 226 households and a few larger public buildings.
All public buildings should be connected to the DH grid, as well as 90% of the households. The
technical concept considers a small biomass CHP (combined heat and power) unit with 112 kWel for
the baseload, an 800 kWth biomass boiler and a 2.2 MWth natural gas peak load boiler. A buffer
storage tank could decrease the peaks after night setback time in the morning, when most households
start heating again. Biomass (e.g. wood chips) is available in this region.
The municipality of Ljutomer in Slovenia selected the industrial zone for developing a DHC
project. A biomass CHP with 448 kWel, a 2 MWth biomass boiler, a 4 MWth natural gas peak load
boiler, a 90 m³ buffer storage tank and a 1.2 MWth biomass steam boiler is considered. This scenario
also covers the cooling needs from a dairy with an absorption chiller, operated with the DH grid.
The technical concept for the city of Ozalj in Croatia includes a 25 MWth biomass boiler,
30,000 m² flat plate solar collectors and a fuel oil peak load boiler. The solar collectors are in
combination with a 40,000 m³ seasonal thermal storage, the biomass boiler with a 300 m³ thermal
storage.
Air quality during the heating season is quite bad in Visoko in Bosnia and Herzegovina due to
heavy use of coal for heating. Existing heating systems are mainly individual ones and currently
dominated by coal as the cheapest energy source on the market. Therefore, the concept plans a new
DH grid using a 6.3 MWth heat pump (from the river) as well as 5,000 m² solar thermal collectors in
combination with a 13,500 m³ seasonal storage, plus a natural gas peak load boiler. About 150 private
houses, 30 collective housing facilities and 6 public buildings are planned to be connected.
The concept for Letnjikovac in Šabac (Serbia) includes a biomass boiler with 1.5 MWth and a
3.5 MWth fuel oil boiler to connect public buildings and about 248 households. The feasibility study
shown that the DH grid is economically valuable, due to the low grid density.
Šabac in Serbia has an existing DH system, using natural gas boilers. The concept for the
implementation of renewable energy in the DH grid Šabac includes three biomass boilers with 4.5
MWth nominal capacity each. This leads to about 61% coverage of the annual heat demand with
renewable energy.
The new area Zajcev Rid in Karposh (Macedonia) could be connected to a DH grid, using a 15
MWth ground water heat pump, 5,000 m² solar thermal collectors, in combination with a 55,000 m³
seasonal storage, plus a fuel oil peak load boiler. Using the DH grid for cooling in summer (15 MWth
electr. chiller) is an option for the cooling.
Table 1. Technical data of the 7 technical DHC concepts in the CoolHeating target
municipalities
Cven
(Slovenia)
Ljutomer
(Slovenia)
Ozalj
(Croatia)
Visoko (BiH)
Letnjikovac
(Serbia)
Šabac
(Serbia)
Karposh
(Macedonia)
DH grid length incl. consumer
connections [m]
3,400
4,175
16,586
5,500
7,656
existing
9,500
Grid density [kWh/m/a]
934
3,524
3,873
3,482
462
4,467
Annual heat losses of the DH grid
[%]
19
6
5
6
17
11
Annual heat losses of the DH grid
[MWh/a]
745
915
3,029
1,129
738
5,400
Consumer needs heat [GWh/a]
2.24
10.94
17
3.54
42.44
Heat for wood drying for CHP
operation [GWh/a]
0.94
3.77
Total heat for DH grid incl. losses
[GWh/a]
3.93
15.63
66.41
18.13
4.28
37.69
from
biomass
47.84
Temperature level for DH grid,
flow/return [°C]
90/65
100/70
90/65
80/60
90/65
110/60
70/40
DH grid operation in summertime
yes
yes
yes
no
no
no
cooling
CHP gross electr. production [kWP
/ MWh/a]
112 /
918
448 /
3,673
Share of total heat for DH from
CHP [%]
48
48
Share of total heat for DH from
biomass boiler [%]
49
51
72
91
61
Share of total heat for DH from
solar thermal [%]
24
16
11
Share of total heat for DH from
heat pump [%]
79
88
Share of total heat for DH from
fossil peak boiler [%]
3
2
4
5
9
39
1
Thermal storage [m³]
50
90
40,000
13,500
60
200
55,000
3.2. Calculation of the Indicators
Information and data on investments and fuel costs were collected and calculated for all target
projects, considering specific circumstances of each municipality. For the calculation of environmental
indicators, emissions factors have been used from European Environment Agency, EMEP/EEA air
pollutant emission inventory guidebook (https://www.eea.europa.eu//publications/emep-eea-
guidebook-2016, [22]. The focus was on four environmental indicators namely: CO2, NOx, SO2 and
PM (PM2.5 and PM10) and two economic indicators namely investment and O&M (incl. fuel) costs.
The considered life time was 20 years. A realistic heat demand for each target community was
assumed, the same for the reference case (existing solution) and the new case (CoolHeating project)
for sake of comparison. For electricity, grid emission factors have been used taking into account the
mixed production portfolio of power supplier (so called net emission factors). For the calculation of
investment and fuel costs, real market prices were used. In estimation of investment costs for the
reference case (existing solution), one replacement of all equipment and facilities in the predicted life
time of 20 years was supposed.
Table sheets of all sub-indicators were formed for each target community, and then economic
and environmental sub-indicators were summarized for all projects in table 2 and table 3, respectively.
As it can be seen from Table 2, for four of five target community under consideration, namely
for the Municipality of Visoko in Bosnia and Herzegovina, for the Municipality of Cven in Slovenia,
for the Municipality of Ozalj in Croatia, and for the Municipality of Karposh in Macedonia, the
CAPEX indicators are higher for the CoolHeating option then for the reference cases. However, the
life-time fuel costs of the reference cases were by far higher for all target communities, giving a
ground for preference of the CoolHeating option.
Table 2. Economic indicators
Investment
(€/a)
Fuel cost
(€/a)
CAPEX
(€/MWh)
OPEX
(€/MWh)
Municipality of Visoko, Bosnia and Herzegovina, Heat demand of 20,000.00 MWh/a
Reference situation (Business as
usual):
1,033,830.0
16,390,843.6
51.7
40.98
CoolHeating project:
5,000,000.0
6,443,544.7
250.0
16.11
Savings in Life time of 20 years
-3,966,170.0
9,947,298.9
Municipality of Cven, Slovenia, Heat demand: 5,732.00 MWh/a
Reference situation (Business as
usual):
1,536,000.0
6,427,938.8
268.0
56.07
CoolHeating project:
1,995,000.0
2,201,163.0
348.0
19.20
Savings in Life time of 20 years
- 459,000.0
4,226,775.5
Municipality of Letnjikovac, Serbia, Heat demand: 4,274.00 MWh/a
Reference situation (Business as
usual):
250,000.0
4,987,369.7
58.5
58.3
CoolHeating project:
100,000.0
2,223,274.7
23.4
26.0
Savings in Life time of 20 years
150,000.0
2,764,094.7
Municipality of Ozalj, Croatia, Heat demand: 59,366.3 MWh/a
Reference situation (Business as
usual):
856,147.88
61,220,964.3
14.42
51.56
CoolHeating project:
21,614,400.0
20,166,373.4
364.09
16.98
Savings in Life time of 20 years
-20,758,252.12
41,054,590.9
Municipality of Karposh, Macedonia, Heat demand: 47,560.1 MWh/a
Reference situation (Business as
usual):
3,480,000.0
2,467,165.6
73.17
51.87
CoolHeating project:
5,407,000.0
881,378.7
113.69
18.53
Savings in Life time of 20 years
- 1,927,000.0
1,585,786.9
TOTAL for 5 target comminities of SouthEast Europe
Reference situation (Business as
usual):
7,155,977.88
91,494,282.0
52.26
50.52
CoolHeating project:
34,116,400.0
31,915,734.5
249.15
17.77
Savings in Life time of 20 years
-26,960,422.12
59,578,547.5
Thus, if the CoolHeating projects are implemented, total fuel cost savings would be
59,578,547.5 EUR for the communities in a period of 20 years. This is 2.2 times more than the total
investment in all CoolHeating projects.
Table 3 summarizes the environmental indicators for all five communities. Considerable savings
in emissions, namely CO2, SO2, NOx and PM10 and PM2.5 are achieved in the CoolHeating option for
all 5 target communities. So, from the environmental aspect, the CoolHeating concept indisputably
prevail over the option of reference case.
Table 3. Environmental indicators
Emission
CO2 (t)
Emission
SOx (t)
Emission
NOx (t)
Emission
PM10 (t)
Emission
PM2.5 (t)
EnCO2
(t/MWh)
Municipality of Visoko, Bosnia and Herzegovina, Heat demand of 20,000.00 MWh/a
Reference situation
(Business as usual):
131,871.0
238.27
1,728.21
635.48
632.87
0.330
CoolHeating project:
67,406.44
120.12
1,166.58
9.15
9.15
0.169
Savings in Life time
of 20 years
64,464.6
118.1
561.6
626.3
623.7
Municipality of Cven, Slovenia, Heat demand: 5,732.00 MWh/a
Reference situation
(Business as usual):
2,803,957.0
131,651.8
458,816.9
23,606.9
18,138.3
24.5
CoolHeating project:
3,635.4
32.15
8.45
293.35
293.35
0.032
Savings in Life time
of 20 years
2,800,322.5
131,619.7
458,808.5
23,313.6
17,845.0
Municipality of Letnjikovac, Serbia, Heat demand: 4,274.00 MWh/a
Reference situation
(Business as usual):
1,326.31
71.73
26.29
649.13
649.04
0.016
CoolHeating project:
3,002.35
26.89
23.13
205.62
205.41
0.035
Savings in Life time
of 20 years
-1,676.0
44.8
3.2
443.5
443.6
Municipality of Ozalj, Croatia, Heat demand: 59,366.30 MWh/a
Reference situation
(Business as usual):
214,023.2
504.61
793.95
2,300.22
2,291.54
0.180
CoolHeating project:
10,649.45
9.92
0.09
0.09
0.09
0.009
Savings in Life time
of 20 years
203,373.8
494.7
793.9
2,300.1
2,291.5
Municipality of Karposh, Macedonia, Heat demand: 47,560.10 MWh/a
Reference situation
(Business as usual):
465,676.6
770.88
6,955.89
755.69
755.69
0.489
CoolHeating project:
225,110.3
354.48
3,787.24
29.40
29.40
0.236
Savings in Life time
of 20 years
240,566.3
416.40
3,168.60
726.30
726.30
TOTAL 5 target comminities of SouthEast Europe
Reference situation
(Business as usual):
3,616,854.1
133,237.3
468,321.24
27,947.4
22,467.4
1.32
CoolHeating project:
309,803.94
543.56
4,985.49
537.61
537.40
0.11
Savings in Life time
of 20 years
3,307,050.1
132,693.7
463,335.75
27,409.8
21,930.0
3.3. Single Criteria Analysis – discussion of the results
Sustainability indicators have been calculated and then summarized for all 5 case studies as
shown inTable 4.
Table 4. Results of Environmental and Economic indicators – summary of all 5 target
communities
RES Scenario
OPTION 1
Business as usual case
OPTION 2
CoolHeating scenario
SI
Units
EnCO2
kg/MWh
1322.35
113.22
EnSO2
kg/MWh
48.65
0.198
EnNOx
kg/MWh
171.01
1.82
EnPM
kg/MWh
10.21
0.196
EcCAPEX
EUR/MWh
52.26
249.15
EcOPEX
EUR/MWh
50.52
17.77
When SCA is applied by simple comparison of indicators of two options under consideration,
namely the reference business-as-usual case and the CoolHeating concept scenario, it can be noted
that, from the environmental aspect – i.e. considering environmental indicators of emissions,
CoolHeating option has an advantage over the reference case (traditional heating option), no matter
which emission indicator is considered. However, the EcCAPEX in the CoolHeating option is not a
preferable. When life-time fuel costs are considered (EcOPEX), the CoolHeating option is again
preferable over the reference case by far. The presented examples show that, within SCA, the selection
of the optimal option for the power system depends exclusively on selected criteria. Notwithstanding
of that, it is worth to note that five of six single criteria give an advantage to CoolHeating option,
while only one single criterion gives advantage to the reference case i.e. the business as usual case
―doing nothing‖.
3.4. Multicriteria sustainability assessment – discussion of the results
Under MSA, all set criteria are considered at the same time. Different economic and
environmental criteria are adopted by respective weighting factors, to measure the influence of each
effecting factor. Then, indicators adopted by weighting factors are agglomerated into a general index
of sustainability. General indices are formed through the following procedure, [15-18]:
- Formation of vectors
).....(1m
xxx
of all input parameters (characteristics of system) which are
necessary for full quality evaluation of the system; in the work, these characteristics are expressed
by two criteria i.e. two groups of sustainability indicators, EnI (Environmental Indicators) and EcI
(Economic Indicators).
- Formation of vectors of specific criteria
m
qqq ,........,( 1
), by which input parameters
m
xx ,...,
1
are evaluated (in this case it is costs in EUR or emissions in tonnes divided by heat production in
MWh in life time of 20 years) and then normalized (i.e. divided by maximum xi value).
- Introduction of weighting factors
,0),.....( 1 im wwww
1....
1 m
ww
, by which
sustainability rate of the considered cases is expressed by means of additive aggregate function,
or synthesized function (general index) given by relation:
Q+(q;w) = wi qi (1)
As final result of the MSA procedure, a priority list of the considered options is obtained. The
general index of sustainability is derived in this work under the reference case (doing nothing) and the
CoolHeating concept option, for a wide range of different combination of weighting factors. Which
combinations of weighting factors are applied depend on the nature of the system under consideration,
environment and economic issues of the area, as well as on the specific situation of the area.
Generally, experts and decision makers together define values of specific weighting factors, to provide
a realistic and reliable sustainability rating of the options under consideration. As a starting point in the
analysis i this work, the authors have assigned equal weighting factors for the air quality in
southeastern European communities, and the economic situation (i.e. economic power of consumers
and GDP).
Following the procedure described above, values of weighting factors and vectors of specific
criteria (normalized sustainability indicators values), and general indices with final ranking of the
options are given in Table 5.
Table 5. Weighting factors (w), specific criteria vectors (q) and general indices (Q)
RES Scenario
REFERENCE CASE
qi
COOLHEATING
CASE
qi
SI
wi
EnCO2
0.125
1
0.0856
EnSO2
0.125
1
0.0041
EnNOx
0.125
1
0.0106
EnPM
0.125
1
0,0192
EcCAPEX
0.250
0.2098
1
EcOPEX
0.250
1
0.3517
Q
0.8025
0.3529
Ranking
2
1
Generally, obtained results clearly confirm that CoolHeating scenario is preferable over the
reference case. It is worth to mention that a wide range of values of weighting factors against the basic
(equal) weighting factors distribution have been investigated, as a part of the MSA sensitivity analysis.
If any reasonable combination of weighting factors is applied, the CoolHeating option is the
preferable, i.e. more sustainable scenario. The performed sensitivity analysis points to the stability of
the CoolHeating scenario option as well. The analysis has shown that if any advantage was given to
Environmental criteria, the CoolHeating project becomes even more preferable compared to the
situation when equal distribution of weighting factors to economic and environmental criteria is
applied. Furthermore, when an advantage is given to economic criteria over environmental criteria,
CoolHeating project is still preferable in a wide range of weighting factors applied. After considering
which weight factors change the ranking of the options, it can be concluded that the CoolHeating
scenario is preferable over the reference (doing nothing) scenario until economic indicators are
weighted by 94% and environmental indicators by 6%, whereby assigning equal importance to the
Economic group of indicators (+47% each) while the Environmental indicators weight only at 1.5%
each. Special attention must be given to the EnCO2 indicator under current and future climate change
mitigation policy which is much better for the CoolHeating project during the whole life time.
In addition, the effects to the increase in employment, local income generation and rural
development have been considered. Evaluating those social indicators as non-valuable characteristics,
CoolHeating option is shown to be preferable option from the social aspect.
4. Conclusions
In this work, SCA and MSA were combined to investigate the sustainability of the heating
sector transition in southeastern European countries from traditional fossil-based towards new modular
renewable-based heating and cooling systems. Sets of economic and environmental indicators were
first defined, while social aspect were analyzed by non-valuable indicators to support the sustainability
analysis. Forecasts of the demands and determination of the capacities of the heat production units, as
well as optimizations of the operating modes itself, were performed by the specialized software
EnergyPRO.
The indicative results presented here show that the CAPEX for four of five target community
under consideration, namely Municipality of Visoko in Bosnia and Herzegovina, Municipality of Cven
in Slovenia, Municipality of Ozalj in Croatia and Municipality of Karposh in Macedonia is higher for
the CoolHeating option than for the reference case. The total lite-time fuel costs are by far higher for
all target communities in the option of the reference case (business as usual - doing nothing), giving a
ground for preference to an option of the CoolHeating concept. Thus, if CoolHeating projects are
implemented, total 20 years life-time savings in fuel costs would be 59,578,547.5 EUR for the 5
communities, which is 2.2 times larger than the total investment costs in CoolHeating projects in all 5
communities. Furthermore, considerable savings in emissions, namely CO2, SO2, NOx and PM10 and
PM2.5 are achieved in the CoolHeating scenarios for all 5 target communities. Total savings in CO2
emissions in lifetime of 5 target communities are over 3,300,000 tonnes. So, from the environmental
aspect, the CoolHeating concept indisputably prevail over the option of reference case.
Obtained results of multicriteria sustainability assessment improve and strengthen SCA results
while clearly confirming that the CoolHeating scenario is preferable over the Reference case. It is
worth to mention that a wide range of values of weighting factors against the basic weighting factors
distribution have been investigated, as a part of sensitivity analysis. If any reasonable combination of
weighting factors is applied, the CoolHeating option is the preferable i.e. more sustainable scenario.
Acknowledgements
The authors would like to thank the target municipalities of the CoolHeating project for their
contributions. The authors would like to thank the European Commission and the Innovation and
Networks Executive Agency (INEA) for the support of the CoolHeating project. CoolHeating has
received funding from the European Union`s Horizon 2020 research and innovation programme under
grant agreement No 691679. The project duration is January 2016 to December 2018. The sole
responsibility for the content of this paper lies with the authors. It does not necessarily reflect the
opinion of the European Union. Neither the INEA nor the European Commission are responsible for
any use that may be made of the information contained therein.
Nomenclature
EcCAPEX, EUR/MWh – investment indicator
EcOPEX, EUR/MWh – O&M indicator
EnCO2, kg/MWh – CO2 indicator
EnSO2, kg/MWh – SO2 indicator
EnNOx, kg/MWh – NOx indicator
EnPM, kg/MWh – PM indicator
q – specific indicator
Q – Sustainability index
x – weighting factor
References
[1] School of Business, Engineering and Science, Halmstad University Sweden, International
review of district heating and cooling, Open Access Article, Energy, 137 (2017) pp. 617-631.
[2] European Commission. An EU strategy on heating and cooling. Communication COM. 2016.
pp. 51. Brussels 2016.
[3] Werner, S, International review of district heating and cooling, Energy, 137 (2017), pp. 617-
631.
[4] Sayegh, MA., Danielewicz, J., Nannou, T., Miniewicz, M., Jadwiszczak, P., Piekarska, K.,
Jouhara, H., Trends of European research and development in district heating technologies,
Renewable and Sustainable Energy Reviews, 68 (2017) pp. 1183–1192.
[5] Connolly, D, Lund, H, Mathiesen, BV, Werner, S, Möller, B, Persson, U, Boermans, T, Trier,
D, Østergaard, PA, Nielsen, S: Heat Roadmap Europe: Combining district heating with heat
savings to decarbonise the EU energy system, Energy Policy, 65 (2014) pp. 475-489.
[6] Lund, H, Duic, N, Østergaard, PA, Mathiesen, BV, Smart energy systems and 4th generation
district heating, Energy, 2016, 110:1-4.
[7] Rutz, D., Janssen, R., Worm, J., Doczekal, C., Zweiler, R., Puksec, T., Duic, N., Sunko, R.,
Sunko, B., Gjorgievski, V., Dimov, L., Markovska, N., Bozikaliev, V., Rajakovic, N., Batas
Bjelic, I., Kazagic, A., Redzic, E., Tresnjo, D., Jerotic, S., Mladenovic, B., Fejzovic, E., Babic,
A., Petrovic, M., Kolbl, M., The role of biomass for small district heating grids for South-
Eastern Europe – The CoolHeating project, Proceedings, 26th European Biomass Conference
and Exhibition, Copenhagen, Denmark, May 2018.
[8] Rutz, D., Janssen, R., Worm, J., Doczekal, C., Zweiler, R., Puksec, T., Duic, N., Sunko, R.,
Sunko, B., Gjorgievski, V., Dimov, L., Markovska, N., Bozikaliev, V., Rajakovic, N., Batas
Bjelic, I., Kazagic, A., Redzic, E., Tresnjo, D., Jerotic, S., Mladenovic, B., Fejzovic, E., Babic,
A., Petrovic, M., Kolbl, M., Small heating grids for communities in Balkan countries: The
CoolHeating Project, Proceedings, 5th International Solar District Heating Conference, Graz,
Austria; 11 and 12 April 2018.
[9] Rutz, D., Mergner, R., Janssen, R., Soerensen, P.A., Jensen, L.L., Doczekal, C., Zweiler, R.,
Pukšec, T., Duić, N., Doracic, B., Sunko, R., Sunko, B., Markovska, N., Gjorgievski, V.,
Bozhikaliev, V., Rajkovic, N., Bjelic, I.B., Kazagic, A., Redzic, E., Smajevic, I., Jerotic, S.,
Mladenović, B., Fejzovic, E., Babić, A., Petrovic, M., Kolbl, M. (2017b) The Combination of
Biomass with Solar Thermal Energy and other Renewables for Small Heating Grids: The
Coolheating Project, Proceedings, the 25th European Biomass Conference and Exhibition,
Stockholm, Sweden; ISBN: 978-88-89407-17-2; DOI: 10.5071/25thEUBCE2017-5BV.2.6, pp.
1896 – 1898.
[10] Rama M., Mohammadi S, Comparison of distributed and centralised integration of solar heat in
a district heating system, Energy, Volume 137, 15 October 2017, pp. 649-660.
[11] Winterscheid, C., Dalenback J., Holler, S, Integration of solar thermal systems in existing
district heating systems, Energy, 137 (2017) pp. 579-585.
[12] Buoro, D., Pinamonti, P, Reini, M., Optimization of a Distributed Cogeneration System with
solar district heating, Applied Energy, Volume 124, July 2014, pp. 298-308.
[13] Soltero, V.M., Chacartegui, R., Ortiz, C., Velázquez, R., Potential of biomass district heating
systems in rural areas, Energy, Volume 156, August 2018, pp. 132-143.
[14] Ziemele, J., Cilinskis, E., Blumberga, D., Pathway and restriction in district heating systems
development towards 4th generation district heating, Energy, Volume 152, June 2018, pp. 108-
118.
[15] Udomsri, S., Bales, C., Martin, A.R., Martin, V., Decentralized cooling in district heating
network: System simulation and parametric study, Applied Energy, Volume 92, April 2012, pp.
175-184.
[16] Kveselis, V., Dzenajavičienė, E.F., Masaitis S., Analysis of energy development sustainability:
The example of the Lithuanian district heating sector, Energy Policy, Volume 100, January
2017, pp. 227-236.
[17] Dombi, M., Kuti, I., Balogh, P., Sustainability assessment of renewable power and heat
generation technologies, Energy Policy, Volume 67, April 2014, pp. 264-271.
[18] Begic, F., Afgan, N., Sustainability Assessment Tool for the Decision Making in Selection of
Energy System—Bosnian Case, Energy, Vol. 32, Issue 10, pp. 1979–1985, 2007.
[19] Begic, F., Afgan, N., Kazagic, A., Multi-criteria Sustainability Assessment - A Tool for
Evaluation of New Energy System, Thermal Science, Vol. 11, Issue 18, pp. 43-53, 2007.
[20] Mourmouris, J.C., Potolias, C., A multi-criteria methodology for energy planning and
developing renewable energy sources at a regional level: A case study Thassos, Greece, Energy
Policy, Vol. 52, pp. 522–530, 2013.
[21] Kazagic, A., Merzic, A., Redzic, A., Music, M., Power Utility Generation Portfolio
Optimization as Function of Specific RES and Decarbonisation Targets - EPBiH Case Study,
Applied Energy, 135 (2014), pp. 694-703.
[22] European Environment Agency, EMEP/EEA air pollutant emission inventory guidebook,
https://www.eea.europa.eu//publications/emep-eea-guidebook-2016, 2016.
Submitted: 7.01.2019.
Revised: 27.05.2019.
Accepted: 6.06.2019.
