Life Cycle Assessment of Environmental Impact of Lighting Systems, Kyoto, Japan

Abstract

The artificial lighting sector consumes around one-fifth of world electricity production in use stage. It generates significant environmental impacts. In order to evaluate and manage these impacts throughout a life cycle of lighting system, a standardized scientific method was developed: The Life Cycle Assessment (LCA). The LCA of an incandescent, compact fluorescent and LED lamps has been achieved. They provide a decision support tool to guide the Ecoconception and allow the reducing of human footprint on his environment.

Full text

Life Cycle Assessment of Environmental Impact of Lighting Systems,
Kyoto, Japan
A. Vandevoorde1, G. Zissis1, M. Mequignon2, Y. Cressault1
1 Université de Toulouse, LAPLACE, 118 route de Narbonne, 31062 Toulouse cedex 9, France
2 Université de Toulouse , Laboratory of Applied Studies and Research in Social Sciences, 115D route de
Narbonne BP 67701, 31077 Toulouse cedex 4, France
Contact: alexis.vandevoorde@laplace.univ-tlse.fr
ABSTRACT
The artificial lighting sector consumes around one-fifth of world electricity production in use stage. It
generates significant environmental impacts. In order to evaluate and manage these impacts throughout
a life cycle of lighting system, a standardized scientific method was developed: The Life Cycle
Assessment (LCA). The LCA of an incandescent, compact fluorescent and LED lamps has been
achieved. They provide a decision support tool to guide the Ecoconception and allow the reducing of
human footprint on his environment.
INTRODUCTION
Reducing the man’s environmental impact on the planet is one of the most important challenges of our
century. In many sectors, it concerns the global scale such as the depletion of energy resources and
climate change but also the local scale with the use of chemicals.
Lighting has become an essential element of today’s society for esthetics, comfort or security reasons.
There are around 30 billion light artificial sources around the world consuming 3400 TWh of electricity
in 2005, equivalent to 19% of the total world consumption [1].
Because it’s an important source of environmental impact, lighting domain is potentially holder of
solutions. Since 2009, The European Ecodesign Directive sets minimal energy efficiency for lighting
systems. Thus, incandescent light bulb too inefficient have gradually been banned from sale between
2009 and 2012 [2] in favor of most efficient and environmentally friendly lighting systems during use :
fluorescent bulb firstly, halogen lamp next, and LED lamp today.
A real energy efficiency of lighting system during using stage is capital in order to limit environmental
impact. And what about the others stages of life cycle such as manufacturing step also requires resources,
recycle or waste disposal? Considering the totality of life cycle, what is most efficient lighting system?
To take into account environmental impact of lighting system throughout their life cycle, a scientific
and standardized method was developed with an holistic approach: the Life Cycle Analysis (LCA).
THE LIFE CYCLE ANALYSIS
LCA is an eco-design tool that realizes an environmental impact assessment of product at each stage of
its life cycle. The tool is a standardized method ISO14040 that defines four iterative steps, each one
describes in ISO 14044.
The life of the lighting system could be divided into several stages from its production, to its
transportation, its usage and its end of life. Each of these stages is defined by a set of processes
characterized by inputs and outputs flows of matter and energy.
In the first place, it needs to define the system boundary and its Functional Unit (FU), i.e. a physical
quantity allowing to give a reference. It defines the product function by which the impacts will be

defined and normalized in order to compare the results of numerous LCA.
In a second phase, the inventory formed by inputs and outputs of matter and energy is produced for
each stage of life system. This inventory should be limited to fixed borders of the system and its FU.
Next, this inventory is filled with a database in an LCA software that models environmental impacts
generate by system studied. Different valuation methods are then combined to evaluate the spectrum of
environmental impacts of a lighting system.
Finally, it should be analyzed these results to characterize the environmental performance of the system,
compare it to others lighting system with the same FU, reveal environmental points needing an action
and rank the opportunities for improvement to engage an ecodesign process.
APPLICATION TO THE LIGHTING SYSTEMS
LCA of three lighting systems was conducted using free software named OpenLCA, the Ecoinvent
database and manufacturing data provided by The United States Department of Energy [2]. The FU
chosen is Mlm.hr (Megalumen.hour) for its lighting system performance integration. For comparison
purposes, an equivalence between three products is calculated through a FU coefficient (Tab 1).
Incandescent
Compact fluorescent
(CFL)
LED
Power consumption (W)
60
15
12.5
Lumen output (lm)
900
825
812
Lamp lifetime (h)
1500
8000
25000
Total lifetime light output (Mlm.h)
1.35
6.6
20.3 (reference)
Functional Unit coefficient
20.3/1.35=15.04
20.3/6.6=3.08
1
Tab 1 : Characteristics of lighting system studied and equivalence calculation
What technology is the least impactful to the environment?
To start, the global environmental impact, i.e. a combination of representative indicators, is calculated
for lighting systems produced in China, transported in Europe by boat via the Suez Canal and used in
France.
For systems referred, LED-lamp is the least impacting technology for the environment generating 27%
of the environmental impact of an incandescent lamp over its entire life cycle and 7% less than the
compact fluorescent lamp.
This is mainly explained by the long life of LED-lamp (25 000 h) which generated impacts are
100%
34% 27%
0,00%
20,00%
40,00%
60,00%
80,00%
100,00%
Global environmental
impact
Incandescent CFL LED
Fig 1: Global environmental impact comparison between incandescent, CFL and LED lamps - China production ; Use
France

distributed over a longer period than its analogue (1500 h and 8000 h respectively for incandescent and
compact fluorescent lamp).
What is the stage of the life cycle generating the most significant environmental impact?
Material Manufacturing Transport Use End of life
Incandescent 5,26% 8,44% 2,06% 83,93% 0,31%
CFL 13,06% 15,48% 0,33% 70,89% 0,25%
LED 24,04% 2,79% 0,13% 72,98% 0,06%
Tab 2: Distribution of the global environmental impact by stage of the life cycle for an incandescent, compact fluorescent
and LED. China Production, Use France.
Whatever the system considered, the use stage causes the most environmental impact by comparison to
the others stages of the life cycle with respectively 83%, 73% and 71% for incandescent lamp, LED and
compact fluorescent lamp (Tab 2). Indeed, these systems consume an important quantity of electricity
during their use stage.
The manufacturing stage, which is the assembly of material composing the system, is the second stage
most impacting the environment concerning incandescent (8%) and compact fluorescent lamp (15%).
The assembly requires high power consumptions.
Conversely, for the LED-lamp, the step of providing the material impact is the second stage most
impacting the environment after the use phase. LED manufacturing requires amount of primary
resources considered critical because exhaustible.
Transport and end of life, with low percentage (<2%) have a negligible global environmental impact by
comparison with other stages.
The strong dependence of the environmental impact to the energy mix of the use phase
Secondly, the global environmental impact is calculated for systems produced in China, transported in
Europe by boat via the Suez Canal but used in Germany.
When lighting systems are used in Germany, the environmental performance gap between the LED and
the incandescent lamp on one side, the LED-lamp and compact fluorescent lamp on the other, is more
important than when used in France. In other words, replacing incandescent or compact fluorescent
lamps is even more interesting in Germany than in France from an environmental point of view.
This is a consequence of differences in energy mix between two countries. The French energy mix is
dominated by nuclear energy (74.3%) opposed to the German energy mix dominated by coal, natural
gas and oil (59.1%) [3]. The global environmental impact of the mix is different. This is reflected on
environmental impact of the lighting systems and especially as the use phase, energy intensive, is the
most impacting life cycle.
100%
30%
9%
0,00%
20,00%
40,00%
60,00%
80,00%
100,00%
Global environmental
impact
Incandescent CFL LED
Fig 2: Global environmental impact comparison between incandescent, CFL and LED lamps - China production; Use
Germany

CONCLUSION
Whatever the lighting system considered (incandescent, CFL or LED), the use phase generates the
majority of the environmental impact of the system lifecycle (respectively 84%, 71%, 73%).
If we consider its entire life cycle, LED technology is more efficient from an environmental perspective
than incandescent and CFL lamp.
However, the energy source for power generation affects these conclusions and modulates both the
environmental impact of the different stages of the life cycle of a system, but also their respective
performance.
The major challenge of these conclusions is twofold. Through its multi-criteria approach, LCA allows
to :
o Identify the main sources of environmental impacts and prevent pollution transfers related to various
alternatives considered by eco-design;
o Provide an overview of the impacts generated by a product to bring elements of aid in the decision
to firstly distributor (choice of the least impactful technology ...), the public decision-maker on the other
(choice of value chain ...) and to regulatory and standardization authority finally.
This set of findings corroborates earlier studies of the environmental impact of lighting systems [4].
Ultimately, it will be necessary to multiply the LCA studies of lighting systems to improve the
knowledge in terms of environmental impacts of these complex systems. Given the importance of the
resources needed for their implementation, harmonization of LCA methods and data acquisition modes
is vital to facilitate their operational capability. Finally, the LCA tool must be able to account for the
complexity of the environment in sustainable product design by linking the environmental impacts with
the cost of environmental externalities and incorporating new categories of impacts.
REFERENCES
[1]
Earth Policy Institute, «World Electricity Consumption for Lighting by Sector and Potential
Electricity Savings,» 2005.
Available: http://www.earth-policy.org/datacenter/pdf/book_wote_energy_efficiency.pdf.
[2]
Ministère de l'Ecologie, de l'Energie, du Développement Durable et de l'Aménagement du
territoire, «Grenelle Environnement : Convention sur le retrait de la vente des ampoules à
incandescence et la promotion des lampes basse consommation,» Paris, 2008.
[3]
U.S. Department of Energy, «Life Cycle Assesments Of Energy and Environmental Impacts of
LED lighting Products,» 2012.
[4]
The World Bank, «The World Bank : data,» 2013. Available: http://data.worldbank.org.
[5]
Leena Tähkämo, «Life cycle assessment of light sources - Cases studies and review of the
analysis,» 2013.
ACKNOWLEDGEMENTS
I would like to express my special thanks to Leena Tähkämö for her recurring assistance, Ecoinvent,
the world’s leading life cycle inventory database, OpenLCA, a professional LCA software and
NeoCampus, a reasearch program for a campus of the future. This work has been financially supported
by IDEX initiative ATS-2E&SC project.