Academic Edi o : F ancesco Noce a
Recei ed: 7 Ma ch 2025
Re ised: 9 Ap il 2025
Accep ed: 11 Ap il 2025
Published: 14 Ap il 2025
Ci a ion: Hoxha, E.; Hosseini, S.M.;
Sous -Ve dague , B.; de Boe , J.
En i onmen al Impac s o Ligh
Sou ces in Buildings: Analysis o
En i onmen al P oduc Decla a ions
(EPDs) in Eu opean Union. Buildings
2025,15, 1279. h ps://doi.o g/
10.3390/buildings15081279
Copy igh : © 2025 by he au ho s.
Licensee MDPI, Basel, Swi ze land.
This a icle is an open access a icle
dis ibu ed unde he e ms and
condi ions o he C ea i e Commons
A ibu ion (CC BY) license
(h ps://c ea i ecommons.o g/
licenses/by/4.0/).
A icle
En i onmen al Impac s o Ligh Sou ces in Buildings:
Analysis o En i onmen al P oduc Decla a ions (EPDs) in
Eu opean Union
End i Hoxha 1,*, Seyed Mo eza Hosseini 2,* , Be na de e Sous -Ve dague 3and Jan de Boe 4
1Depa men o he Buil En i onmen , Aalbo g Uni e si y Copenhagen, A.C. Meye s Vænge 15,
2450 Copenhagen SV, Denma k
2Depa men o A chi ec u e, Design & Media Technology, Aalbo g Uni e si y Copenhagen,
A.C. Meye s Vænge 15, 2450 Copenhagen SV, Denma k
3Ins i u o Uni e si a io de A qui ec u a y Ciencias de La Cons ucción, Uni e si y o Se ille,
41004 Se illa, Spain; [email p o ec ed]
4F aunho e Ins i u e o Building Physics, 70569 S u ga , Ge many; [email p o ec ed].de
*Co espondence: [email p o ec ed] (E.H.); [email p o ec ed] (S.M.H.)
Abs ac : Benchma k s udies o he en i onmen al impac s o buildings o en o e look he
con ibu ion o ligh ing sys ems. This omission p esen s a signi ican knowledge gap, es-
pecially gi en he g owing ocus on ene gy-e icien echnologies and sus ainable building
designs. To add ess his gap, he li e cycle assessmen me hod was used o calcula e he
en i onmen al impac s o ligh ing sys ems, ocusing on he Global Wa ming Po en ial (GWP)
indica o . An in-dep h e iew o da abases and p og ams ac oss he 27 Eu opean Union
membe s a es was also conduc ed. The s udy analyzed bo h he absolu e and ela i e con i-
bu ions o ligh ing sys ems o he o e all en i onmen al impac s o buildings, wi h a speci ic
ocus on he si ua ion in Denma k. A o al o 101 En i onmen al P oduc Decla a ions (EPDs)
co e ing 753 LED ligh ing p oduc s we e iden i ied. Ma e ial- ela ed impac s accoun ed o
1–12% o he o al GWP, while ene gy used du ing ope a ions con ibu ed 6–24%. These
esul s emphasize he impo ance o bo h embodied and ope a ional impac s. Imp o ing
he luminous e icacy o ligh ing sys ems eme ges as a mo e e ec i e and easible s a egy
o educe a building’s GWP han lowe ing o e all ene gy use o g id ca bon in ensi y. In
coun ies wi h high-ca bon elec ici y, educing he ope a ional impac s is c i ical. Elsewhe e,
selec ing ligh ing sys ems wi h low embodied impac s is also essen ial.
Keywo ds: ligh ing sys ems; li e-cycle assessmen ; ca bon emission in ensi y; clima e change
1. In oduc ion
The Eu opean Union aims o educe g eenhouse gas (GHG) emissions d as ically o
1990 le els [
1
], o which he building sec o is esponsible o o e one- hi d [
2
]. The apid
inc ease in global loo a ea and ising a luence ha e signi ican ly inc eased he demand
o he mal and isual com o by buildings’ occupan s. This demand has subs an ially in-
c eased ene gy consump ion and ela ed g eenhouse gas emissions [
3
]. The e o e, building
ene gy consump ion encompasses a ious ac o s such as ligh ing, hea ing, domes ic ho
wa e , ai condi ioning, and cooling [
4
]. Elec ic ligh ing cons i u es a signi ican p opo ion
o his consump ion, accoun ing o app oxima ely 11% and 4% o o al elec ici y use in
he comme cial and esiden ial sec o s, espec i ely [5].
A e iew o he ele an li e a u e on he ene gy consump ion o elec ic ligh ing
e eals ha mos ecen s udies ha e ocused on in eg a ed ligh ing sys ems [
6
,
7
]. These
Buildings 2025,15, 1279 h ps://doi.o g/10.3390/buildings15081279
Buildings 2025,15, 1279 2 o 15
sys ems combine dayligh ing s a egies wi h con en ional and sma ligh ing echnolo-
gies [
8
] o op imize ene gy e iciency. Fo example, a s udy by Ia au o and Zinzi [
9
] e ealed
ha using dynamic clima e-based simula ions ins ead o he EN15193-1 [
10
] s anda d can
educe annual ligh ing ene gy consump ion by 62–78%. A simila s udy by [
11
] in es iga ed
he in eg a ion o LED dimming con ol wi h in e ac i e kine ic lou e s, u ilizing occupan
de ec ion and es ima ion o enhance isual com o , dayligh pe o mance, and elec ic
ene gy consump ion simul aneously. The esul s indica e ha his pa ame ic app oach
educes he ene gy consump ion o elec ic ligh ing by app oxima ely 99% compa ed o
he ligh ing occupancy p o ile o he ASHRAE 90.1 s anda d (ASHRAE, Peach ee Co ne s,
GA, USA). A ela ed s udy [
12
] demons a ed ha implemen ing dayligh -concen a ing
indoo lou e s, in eg a ed wi h LED-linked dimming con ol, esul ed in an 86% educ ion
in he ene gy consump ion o elec ic ligh ing, pa icula ly du ing he ansi ional season.
In he s udy [
13
], i was ound ha e ical ubula dayligh ing de ices (TDDs), combined
wi h LED and a dimming con ol sys em, could educe he ene gy consump ion o elec ic
ligh ing by up o 21% in deep-plan o ice buildings loca ed in ho dese clima es. Acco ding
o Albu e al. [
14
], eimplemen ing dayligh sys em con ol in he case s udied educed he
ope a ional ene gy use by 25% o 75%. Howe e , due o he high impac o e he ligh ing’s
li e ime, he GWP educ ion was limi ed o app oxima ely 10%.
Howe e , ew s udies ha e assessed he en i onmen al impac s o ligh ing sys ems
on elec ic ene gy use in buildings. Two g oups o s udies can be iden i ied, which a e
classi ied in o sma and con en ional ligh ing sys ems. The i s esea ch ca ego y in es i-
ga es a ious ypes o ligh ing and employs bo h occupancy de ec ion and senso -based
op imiza ion o educe elec ic ene gy consump ion signi ican ly. No ably, he e is subs an-
ial po en ial o ene gy sa ings in elec ic ligh ing, wi h app oxima ely 30% achie able
by eplacing Compac Fluo escen Lamps (CFLs) wi h sma ligh -emi ing diodes (LEDs).
Addi ionally, he in eg a ion o sma ligh ing sys ems wi h LEDs has been ound o educe
ene gy consump ion by up o 40% in esiden ial buildings in Sweden [8].
The second ca ego y mos ly ocuses on con en ional ligh ing sys ems by eplacing di -
e en ypes o ligh s wi h high-pe o mance LEDs. S udies conduc ed in a ious coun ies,
including China, Malaysia, Tu key, Bangladesh, and B azil, on educa ional, esiden ial, and
indus ial building ypes con i med he e ec i eness o eplacing adi ional ligh ing wi h
LED. These s udies demons a e signi ican educ ions in ligh ing ene gy consump ion
and ca bon emissions. A s udy conduc ed in China in es iga ed he impac o eplacing
incandescen ligh bulbs wi h compac luo escen ligh s (CFLs) on household ligh ing
elec ici y usage. The esea ch conside ed a ious ac o s, including di e en oom ypes,
daily ligh ing usage pa e ns, he numbe o ligh bulbs pe household and oom, and
seasonal a ia ions. The indings e ealed ha his in e en ion educed ligh ing ene gy
consump ion by 23% o 27% [
15
]. A compa a i e s udy be ween CFL and LED luminai es
ound ha LED luminai es educed g eenhouse gas emissions and cumula i e ene gy de-
mand by 41–50%, mainly due o hei high ene gy e iciency [
16
]. Ano he s udy examined
he ene gy bene i s o LED adop ion in Malaysia by e iewing he ele an esea ch pape s
and conduc ing a li e-cycle assessmen . The indings indica ed ha eplacing 62% o incan-
descen lamps wi h LEDs in esiden ial buildings could esul in an 80% educ ion in ca bon
emissions and 85% in elec ici y bills [
17
]. A simila in e en ion in an indus ial building
in Bangladesh demons a ed a dec ease in ligh ing ene gy usage wi hin a ange o 7% o
15%, which esul ed in a 51% educ ion in ca bon emissions [
18
]. Enhancing con en ional
ligh ing sys ems in his o ical and educa ional buildings in Tu key by eplacing incandes-
cen halogen lamps and luo escen ube ligh s wi h LEDs esul ed in signi ican ene gy
sa ings. Speci ically, his in e en ion led o a 78% educ ion in elec ic ene gy consump ion
in his o ical buildings [
19
] and a 68% educ ion in educa ional buildings [
20
]. Mo eo e ,
Buildings 2025,15, 1279 3 o 15
a s udy conduc ed in B azil in es iga ed he educ ion in elec ic ene gy consump ion
in an educa ional building by e o i ing luo escen ube ligh s wi h LEDs. Li e-cycle
assessmen (LCA) and ield-s udy measu emen s indica ed a 34% educ ion in ligh ing
ene gy consump ion and a 33% dec ease in ca bon emissions [
21
]. A simila in e en ion in
Se bia showed ha eplacing ligh ing sys ems could achie e sa ings o 53% o 62%, wi h
an a e age payback pe iod o abou ou yea s o he analyzed schools [
22
]. Due o he
supe io luminous e icacy o LED luminai es compa ed o con en ional ligh ing echnolo-
gies, hey a e conside ed an en i onmen ally sus ainable ligh ing solu ion [
23
]. Howe e ,
a limi ed numbe o s udies ha e been ocused on analyzing he en i onmen al impac s
o ligh ing sys ems. Using he P oduc En i onmen al Foo p in (PEF) me hodology, Wu
and Su assessed he en i onmen al impac s o an LED low-bay indus ial luminai e [
24
].
Welz e al. compa ed he en i onmen al impac s o ou di e en ligh ing echnologies:
he ungs en lamp, he halogen lamp, he con en ional luo escen lamp, and he compac
luo escen lamp. They con i med ha he luo escen lamps had lowe en i onmen al
impac s compa ed o he o he echnologies [25].
In summa y, esea ch s udies ha ocus exclusi ely on ligh ing ypes and sys ems
p ima ily add ess ene gy e iciency and he esul an educ ion in ca bon emissions wi hin
he scope o elec ic ligh ing use. These s udies o en o e look he con ibu ion o ligh ing
o he o e all ene gy use in ensi y and he en i onmen al impac o he en i e building.
They do no conside he comp ehensi e impac o di e en ligh ing ypes on he building’s
pe o mance. In addi ion, hese s udies neglec he analysis o En i onmen al P oduc
Decla a ions (EPDs). The e o e, new esea ch is needed o in es iga e hese e ec s on
he building scale and compa e hei en i onmen al impac s wi h he impac s o building
ab ic, hea ing, and en ila ion sys ems.
To add ess his knowledge gap, his s udy will ex ensi ely e iew he ac ual s a e o
he published EPDs o ligh ing sys ems and analyze hei impac s when ins alled in each
o he 27 Eu opean Union membe s a es. Fu he mo e, he s udy ocuses on assessing
he impac s o he ma e ials composing he ligh ing (embodied impac s) and hose ela ed
o ene gy consump ion du ing he ope a ional s age (ope a ional impac s). Then, he
en i onmen al impac s o ligh ing a e es ed o p obable co ela ion wi h he luminous
e icacy o each solu ion. Finally, he absolu e and ela i e con ibu ion o ligh ing o he
o e all impac o buildings is calcula ed.
2. Ma e ials and Me hods
The con ibu ion o he ligh ing o he o e all impac s o buildings was calcula ed
ollowing a h ee-s ep me hodology. Fi s , he in o ma ion ela ed o he en i onmen al
impac s o a ious ligh ing sys ems was ob ained h ough an ex ensi e sea ch in he EPDs
da abase and p og ams published in a Eu opean con ex . A e being complied, he da a
we e no malized and analyzed. Then, h ough a building case s udy, he impac s o all
ligh ing sys ems and hei absolu e and ela i e con ibu ions we e assessed.
2.1. Da a Collec ion
The da a collec ion p ocess s a ed by iden i ying da abases and p og ams wi h in o -
ma ion ela ed o he en i onmen al impac s o ligh ing in he Eu opean con ex . A o al o
eigh een na ional da abases [
26
–
43
] and se en p og ams [
44
–
50
] we e iden i ied. Since his
s udy was an ex ension o p e iously published esea ch, he me hod o iden i ying ligh -
ings’ en i onmen al p oduc decla a ions (EPDs) was simila o ha in [
51
]. The inclusion
c i e ia o he da a o be collec ed we e ha he in o ma ion mus ha e been published in
open-access EPDs, and only o sys ems p o iding ligh ing unc ions. Da ase s ela ed o
ligh ing used o o he pu poses, such as e acua ion sys ems, deco a ion, ligh ing oads,
Buildings 2025,15, 1279 4 o 15
e c., we e no included o u he analysis. A e a de ailed, in-dep h sea ch wi hin he
da abases and p og ams, 101 open-access EPDs we e iden i ied, ep esen ing 753 a ious
LED ligh ing sys ems, mainly published in F ench, Danish, Belgian, Ge man, and Du ch
da abases. Fo all EPDs, ex ac ion in o ma ion was collec ed manually by checking all
PDF iles. This in o ma ion included he GHG emissions calcula ed h ough he global
wa ming po en ial (GWP) indica o o all li e-cycle s ages acco ding o EN-15804 [
52
]:
p oduc ion (A1–A3), anspo (A4), assembly (A5), use (B1), main enance (B2), epai (B3),
eplacemen (B4), e u bishmen (B5), decons uc ion (C1), anspo (C2), was e p ocess-
ing (C3), disposal (C4), and load beyond he sys em bounda y (D). The impac s o hese
p oduc li e-cycle s ages a e necessa y o ecognize he embodied impac ela ed o he
ma e ials used o p oduce he ligh ing sys ems. In addi ion, in o ma ion ela ed o powe ,
luminosi y, e e ence se ice li e, and decla ed uni s was collec ed mainly o calcula e he
en i onmen al impac s o he ope a ional s age (B6) o ligh ing sys ems.
2.2. Da a No maliza ion, Classi ica ion, and Analysis
To enable he compa ison o he ligh ing sys ems in e ms o he en i onmen al impac s
and o acili a e hei use in assessing building impac s, hei no maliza ion is necessa y
unde he same uni . Fo hese easons, in his s udy, we ha e ollowed he ecommenda-
ions o he PEP Ecopasspo (Pa is, F ance) [
30
], which ecommends p o iding he impac s
o ligh ing unde a unc ional uni o 1000 lumens o e 35,000 h o use. This unc ional
uni is no in ended o desc ibe he eal luminosi y o he wo king hou s o he ligh ing,
which is se in line wi h uni no maliza ion so as o enable compa ison be ween he a ious
solu ions. I should be s essed ha mos o he EPDs al eady p o ide he impac s unde
ha unc ional uni , while we need o no malize he impac s o he es . The no maliza ion
o da a could be classi ied as no malizing hose da a conce ning he embodied impac s ha
ep esen hose om he p ocesses he ma e ials unde wen om he p oduc ion o he
ligh ing sys em o hei elimina ion a he end o li e, and he impac s o he ope a ional
phase ep esen ing no maliza ion om he use o he ligh s. Fi s , he e e ence se ice li e
p o ided o each ype o ligh ing was con e ed in o hou s o use. This in o ma ion was
hen used o di ide he embodied impac s o ligh ing, which we e mul iplied by 35,000,
ep esen ing he hou s o use. The in o ma ion ela ed o he powe o each ligh ing sys em
was mul iplied by 35,000 o ob ain he ene gy equi ed in kWh o ope a e he ligh unde
he decla ed unc ional uni . The con e sion o ene gy consump ion by ligh ing in impac s
was made possible by mul iplying he ca bon con en o he elec ici y g id p o ided in
kg CO
2
e/kWh [
53
]. De ailed in o ma ion ela ed o all he GWP sco es o each ligh ing
sys em unde he no malized unc ional uni is p o ided in Supplemen a y Ma e ials. In
addi ion, he Supplemen a y Ma e ials p o ides in o ma ion on all he o he ex ac ed
in o ma ion ela ed o ligh ing. The en i onmen al impac s o ligh ing sys ems and hei
luminous e icacy we e also analyzed. To ha end, ou ca ego ies we e c ea ed based on
he li e a u e. All ligh ing wi h a luminous e icacy o up o 50 lm/W was g ouped like he
low-pe o mance ones g ouped in he i s ca ego y. In he second sec ion, ligh ing wi h
a luminous e icacy o 50 and 100 lm/W was ca ego ized as a medium pe o mance. The
hi d high-pe o mance lamp had a luminous e icacy be ween 100 and 150 lm/W, and he
las wi h a la ge luminous e icacy was conside ed as high pe o mance.
2.3. Li e-Cycle Assessmen
The ou -s ep scien i ic alida ion me hod o li e-cycle assessmen (LCA) was applied
o assess a building’s en i onmen al impac s by ollowing he EN15978 [
54
] no m. In he
i s s ep in calcula ing he applied a ibu ional LCA, goal and scope we e de ined as he
unc ional uni he sys em bounda y o he s udy and he en i onmen al indica o o be
Buildings 2025,15, 1279 5 o 15
calcula ed. The unc ional uni ep esen ing a quan i ied desc ip ion o he p ima y unc ion
o he building was de ined as a one-squa e me e g oss loo a ea (GFA) pe yea o a
e e ence se ice li e o 50 yea s [
55
]. The sys em bounda y o he s udy, which in he LCA
indica es he ela ed ma e ials, p ocesses, and ene gy included in he assessmen o impac s,
was limi ed o he building’s li e-cycle s ages o p oduc ion (A1–A3), eplacemen (B4),
ope a ional ene gy use o hea ing, cooling en ila ion and ene gy used o a i icial ligh ing
(B6), was e p ocessing (C3), and disposal (C4). Founda ions, ex e nal walls, windows, oo ,
in e media e slabs, in e nal walls, doo s, and he ligh ing sys em a e o he ways o building
p oduc and ma e ial decomposi ion [
56
] conside ed wi hin he sys em bounda y o he
s udy. Gi en he explo a o y objec i es o his s udy and he u gen na u e o he clima e
change p oblem, hen, he assessmen s we e ocused only on he en i onmen al indica o
o global wa ming po en ial (GWP). Howe e , i dese es o be s essed ha he p ocess
o he assessmen o ano he en i onmen al indica o is simila , and all links o he da a
sou ces a e ully p o ided. The second s ep in he LCA dealing wi h li e-cycle in en o ies
in ol es collec ing o eg ound and backg ound da a. The o eg ound da a gene a ing
he in o ma ion ela ed o he ma e ials and p oduc s employed in he buildings we e
ex ac ed om he BIM model. The e e ence se ice li es used o calcula e he impac s
o he eplacemen (B4) o ma e ials o p oduc s du ing he building’s ope a ional s age
we e ob ained om he gene ic Danish da a [
57
]. Full de ails ela ed o he BIM model,
he ex ac ion o da a, and he hypo hesis o he calcula ion o he en i onmen al impac s
o building ab ics a e p o ided in [
58
]. Fo he backg ound da a con aining in o ma ion
ela ed o he impac s, in ou case, he kg CO
2
e pe uni ma e ial changed be ween he
gene ic OKOBAUDAT lib a y and he Danish EPD lib a y. The li e-cycle in en o y o
ligh ing sys ems has been ea ed sligh ly di e en ly compa ed o ha o building ab ic.
Since he building p ojec assessed in his s udy has no unde gone any ene gy used o
a i icial ligh ing simula ions due o he lack o egula ion by no ms, as in he case o
Denma k, hen ce ain assump ions and hypo heses needed o be made. The quan i ies o
ligh ing sys ems ha e been calcula ed in ela ion o he minimum amoun o luminosi y
o a speci ic a ea, which, in he case o esiden ial buildings, was equal o 500 lux [
59
].
The ene gy equi emen du ing he building’s ope a ional s age and he use p o ile gi en
in [
60
] we e aken in o accoun . We conside ed wo scena ios o he ca bon con en o
elec ici y o ene gy used o a i icial ligh ing. The i s scena io assumed a cons an
ca bon con en o he elec ici y g id o e ime, equal o ha o 2020. The second scena io
conside ed a p og essi e scena io, which assumed a deca boniza ion pa hway o he
elec ici y g id o e ime. In he hi d s ep o he LCA, he impac assessmen , he IPCC
impac assessmen me hod, was used o calcula e he GWP indica o [
61
]. In he las
in e p e a ion s ep o he LCA, he analyses we e ocused on he con ibu ion o he ligh ing
sys ems o he o e all impac s o buildings and a ia ions o he sha e as a unc ion o hei
luminous e icacy.
3. Case S udy
A esiden ial building wi h a g oss loo a ea o 2572 m
2
si ua ed in Denma k was
conside ed o he in es iga ion o he en i onmen al impac s o ligh ing sys ems. Figu e 1
shows he in o ma ion ega ding he building ela ed o he sha e o a eas used o speci ic
pu poses, occupancy p o iles, and he minimum equi ed luminosi y ecommended in
he no m [
59
]. The building p e iously analyzed in [
58
] had a wooden s uc u e and was
chosen as a e y app op ia e p ojec o he aim o his explana o y s udy. The eason
behind his is ha his building had a low GWP sco e, making i a u u e ep esen a i e
p ojec able o each he limi alues se by he Danish go e nmen o limi g eenhouse gas
emissions om he cons uc ion indus y (1). The building had a modula cons uc ion
Buildings 2025,15, 1279 6 o 15
wi h p e ab ica ed insula ed elemen s equi ing only connec ion a he si e. The en elope
was suppo ed by conc e e ounda ions insula ed wi h polys y ene. The building elemen s
had e y low he mal ansmission coe icien s (U- alues) anging om 0.06 W/(m
2
K) o
0.17 (W/m
2
K). The demand o 21.3 kWh/m
2
/yea o hea ing o he building was assu ed
h ough a dis ic connec ion. The elec ici y was pa ially suppo ed by 77 m
2
pho o ol aic
panels and pa ly by 28.1 kWh/m
2
/yea om he g id. A de ailed desc ip ion o he case
s udy, he ma e ials and componen s employed, and all o he de ails a e desc ibed in [
58
].
Buildings 2025, 15, x FOR PEER REVIEW 6 o 16
in he no m [59]. The building p e iously analyzed in [58] had a wooden s uc u e and
was chosen as a e y app op ia e p ojec o he aim o his explana o y s udy. The eason
behind his is ha his building had a low GWP sco e, making i a u u e ep esen a i e
p ojec able o each he limi alues se by he Danish go e nmen o limi g eenhouse
gas emissions om he cons uc ion indus y (1). The building had a modula cons uc-
ion wi h p e ab ica ed insula ed elemen s equi ing only connec ion a he si e. The en-
elope was suppo ed by conc e e ounda ions insula ed wi h polys y ene. The building
elemen s had e y low he mal ansmission coe icien s (U- alues) anging om 0.06
W/(m
2
K) o 0.17 (W/m
2
K). The demand o 21.3 kWh/m
2
/yea o hea ing o he building
was assu ed h ough a dis ic connec ion. The elec ici y was pa ially suppo ed by 77
m
2
pho o ol aic panels and pa ly by 28.1 kWh/m
2
/yea om he g id. A de ailed desc ip-
ion o he case s udy, he ma e ials and componen s employed, and all o he de ails a e
desc ibed in [58].
Figu e 1. Pe cen ages, occupancy p o iles, and he equi ed quan i y o ligh ing o each o he build-
ing’s speci ic a eas.
4. Resul s
Figu e 2 summa izes he absolu e alues o he GWP indica o o all ligh ing sys ems
pe unc ional uni (FU) by p o iding 1000 lumens o 35,000 h, as conside ed o be ope -
a ing in he EU-27 membe s a es. Fu he mo e, he esul s show he ela i e sha e o he
embodied and ope a ional impac s o ene gy used o a i icial ligh ing, lis ed in dec eas-
ing o de o elec ici y g id deca boniza ion. F om he si ua ion in Poland, as he case wi h
he mos ca bonized elec ici y g id, on a e age, he impac o ligh ing sys ems was equal
o 194 kg CO
2
e/FU, while in Sweden, he a e age impac was equal o 18.2 kg CO
2
e/FU,
being he coun y wi h he leas ca bonized elec ici y. This di e ence in esul s be ween
he impac s o ligh ing sys ems as ope a ing in di e en coun ies shows he possibili y o
educing he impac s by a ac o o en in he case o a educ ion in he ca bon con en o
he elec ici y g id. Rega ding ela i e con ibu ions, he embodied impac s in he Polish
case we e on a e age equal o 2%, wi h a a ia ion be ween 0% and 10% depending on
he unc ion o he ligh ing ype and i s luminous e icacy. Fo Sweden, on a e age, he
embodied impac s we e equal o 24%, wi h a a ia ion be ween 2% and 64%. Conse-
quen ly, in he case o o he EU-27 coun ies, he ela i e con ibu ion o he embodied
impac s a ied be ween 1% and 64%.
The analysis o he esul s indica ed he p esence o a ew ou lie s in e ms o impac s.
Thei embodied impac s a e mo e dominan han hose o ope a ion. The easons o his
we e ei he ha hey had e y high luminous e icacy, educing hei need o ope a ing
ene gy, o ha he ma e ials used in hei p oduc ion we e hea y in e ms o GHG emis-
sions. I should be s essed ha Poland, Cyp us, Es onia, Mal a, Czechia, Bulga ia, Ge -
many, I aly, he Ne he lands, I eland, and G eece show esul s abo e he a e age
Figu e 1. Pe cen ages, occupancy p o iles, and he equi ed quan i y o ligh ing o each o he
building’s speci ic a eas.
4. Resul s
Figu e 2summa izes he absolu e alues o he GWP indica o o all ligh ing sys ems
pe unc ional uni (FU) by p o iding 1000 lumens o 35,000 h, as conside ed o be ope -
a ing in he EU-27 membe s a es. Fu he mo e, he esul s show he ela i e sha e o he
embodied and ope a ional impac s o ene gy used o a i icial ligh ing, lis ed in dec easing
o de o elec ici y g id deca boniza ion. F om he si ua ion in Poland, as he case wi h he
mos ca bonized elec ici y g id, on a e age, he impac o ligh ing sys ems was equal o
194 kg CO
2
e/FU, while in Sweden, he a e age impac was equal o 18.2 kg CO
2
e/FU,
being he coun y wi h he leas ca bonized elec ici y. This di e ence in esul s be ween
he impac s o ligh ing sys ems as ope a ing in di e en coun ies shows he possibili y o
educing he impac s by a ac o o en in he case o a educ ion in he ca bon con en o
he elec ici y g id. Rega ding ela i e con ibu ions, he embodied impac s in he Polish
case we e on a e age equal o 2%, wi h a a ia ion be ween 0% and 10% depending on
he unc ion o he ligh ing ype and i s luminous e icacy. Fo Sweden, on a e age, he
embodied impac s we e equal o 24%, wi h a a ia ion be ween 2% and 64%. Consequen ly,
in he case o o he EU-27 coun ies, he ela i e con ibu ion o he embodied impac s
a ied be ween 1% and 64%.
The analysis o he esul s indica ed he p esence o a ew ou lie s in e ms o impac s.
Thei embodied impac s a e mo e dominan han hose o ope a ion. The easons o his
we e ei he ha hey had e y high luminous e icacy, educing hei need o ope a ing
ene gy, o ha he ma e ials used in hei p oduc ion we e hea y in e ms o GHG emissions.
I should be s essed ha Poland, Cyp us, Es onia, Mal a, Czechia, Bulga ia, Ge many,
I aly, he Ne he lands, I eland, and G eece show esul s abo e he a e age Eu opean le el.
In hese coun ies, he ene gy used o a i icial ligh ing accoun s o o e 95% o he
impac s, making i he dominan ac o . The e o e, e o s o educe impac s should ocus
on minimizing ene gy used o a i icial ligh ing needs o using low-ca bon ene gy sou ces
like pho o ol aic panels. Fo o he coun ies, he sha e o hei ligh ing sys ems’ embodied
impac s could be conside ed ela i ely signi ican . Consequen ly, o educe he impac s
o ligh ing sys ems in hese cases, building designe s should no only minimize elec ical
Buildings 2025,15, 1279 7 o 15
ene gy needs and use low-ca bon ene gy sou ces, bu also ca e ully selec sys ems wi h
low embodied impac s.
Buildings 2025, 15, x FOR PEER REVIEW 7 o 16
Eu opean le el. In hese coun ies, he ene gy used o a i icial ligh ing accoun s o o e
95% o he impac s, making i he dominan ac o . The e o e, e o s o educe impac s
should ocus on minimizing ene gy used o a i icial ligh ing needs o using low-ca bon
ene gy sou ces like pho o ol aic panels. Fo o he coun ies, he sha e o hei ligh ing
sys ems’ embodied impac s could be conside ed ela i ely signi ican . Consequen ly, o
educe he impac s o ligh ing sys ems in hese cases, building designe s should no only
minimize elec ical ene gy needs and use low-ca bon ene gy sou ces, bu also ca e ully
selec sys ems wi h low embodied impac s.
Based on hese esul s, we can conclude ha he deca boniza ion o he elec ici y
g id can d as ically educe he en i onmen al impac s o ene gy used o a i icial ligh ing
and should be p io i ized in se e al Eu opean coun ies. The implemen a ion o low-ca -
bon ene gy sou ces like pho o ol aic panels is o p ima y impo ance. In his ein, wi h
an imp o ed ca bon con en o he elec ici y g id, he ela i e con ibu ion o he embod-
ied impac s ela ed o ligh ing sys ems becomes mo e signi ican , making i he nex a ge
o imp o ing he GWP sco e. Howe e , he minimiza ion o ligh ing sys em impac s is a
unc ion o bo h hei luminous e icacy and he ca bon con en o he elec ici y g id.
Figu e 2. A e age GWP sco e o ligh ing sys ems o EU-27 coun ies, and he a ia ion o ela i e
con ibu ions o embodied and ope a ional impac s. The decla ed unc ional uni (FU) is assumed
o be a ligh p o iding 1000 lumens o e 35,000 hou s. Black s a s p esen he absolu e alues o
GWP (kg CO2 e/FU), ed boxplo s p esen ela i e ope a ional impac s (%) and blue boxplo s he
ela i e embodied impac s (%).
Since he subjec o ope a ional ene gy consump ion om ene gy used o a i icial
ligh ing has been ex ensi ely analyzed in p e iously published s udies, in his esea ch,
we in es iga ed he minimiza ion o ligh ing sys em impac s in ela ion o hei luminous
e icacy and he ca bon con en o he elec ici y g id. Gi en he limi a ions o da a ela ed
o he p og ession o he ca bon con en o he elec ici y g id o se e al EU-27 coun ies
and he case-s udy building analyzed he e, he nex analyses a e ocused and a e ep e-
sen a i e o he Danish con ex . To imp o e he unde s anding o he in luence o hese
ac o s and hei ela ionship o he GWP indica o , Figu e 3 shows he co ela ion be-
ween he ligh ing sys em impac s and luminous e icacy unde wo scena ios. One sce-
na io assumes a cons an ca bon con en o he elec ici y g id o e ime, while he second
conside s i s p og essi e deca boniza ion. The esul s showed a s ong co ela ion
Figu e 2. A e age GWP sco e o ligh ing sys ems o EU-27 coun ies, and he a ia ion o ela i e
con ibu ions o embodied and ope a ional impac s. The decla ed unc ional uni (FU) is assumed
o be a ligh p o iding 1000 lumens o e 35,000 h. Black s a s p esen he absolu e alues o GWP
(kg CO
2
e/FU), ed boxplo s p esen ela i e ope a ional impac s (%) and blue boxplo s he ela i e
embodied impac s (%).
Based on hese esul s, we can conclude ha he deca boniza ion o he elec ici y g id
can d as ically educe he en i onmen al impac s o ene gy used o a i icial ligh ing and
should be p io i ized in se e al Eu opean coun ies. The implemen a ion o low-ca bon
ene gy sou ces like pho o ol aic panels is o p ima y impo ance. In his ein, wi h an
imp o ed ca bon con en o he elec ici y g id, he ela i e con ibu ion o he embodied
impac s ela ed o ligh ing sys ems becomes mo e signi ican , making i he nex a ge
o imp o ing he GWP sco e. Howe e , he minimiza ion o ligh ing sys em impac s is a
unc ion o bo h hei luminous e icacy and he ca bon con en o he elec ici y g id.
Since he subjec o ope a ional ene gy consump ion om ene gy used o a i icial
ligh ing has been ex ensi ely analyzed in p e iously published s udies, in his esea ch, we
in es iga ed he minimiza ion o ligh ing sys em impac s in ela ion o hei luminous e icacy
and he ca bon con en o he elec ici y g id. Gi en he limi a ions o da a ela ed o he
p og ession o he ca bon con en o he elec ici y g id o se e al EU-27 coun ies and he
case-s udy building analyzed he e, he nex analyses a e ocused and a e ep esen a i e o
he Danish con ex . To imp o e he unde s anding o he in luence o hese ac o s and
hei ela ionship o he GWP indica o , Figu e 3shows he co ela ion be ween he ligh ing
sys em impac s and luminous e icacy unde wo scena ios. One scena io assumes a cons an
ca bon con en o he elec ici y g id o e ime, while he second conside s i s p og essi e
deca boniza ion. The esul s showed a s ong co ela ion be ween he GWP sco e and he
ligh ing luminous e icacy in bo h scena ios. This co ela ion ollows an exponen ial dec ease
equa ion, wi h Pea son co ela ion coe icien s o R = 0.97 and R = 0.86 o he cons an and
p og essi e imp o emen o elec ici y g id ca bon con en , espec i ely.
In he i s scena io, which assumed a cons an ca bon con en o he elec ici y g id o e
ime, he GWP sco e om ligh ing sys ems wi h di e en luminous e icacy le els ell om
192 kg CO
2
e/FU o 40 kg CO
2
e/FU. A ela i e educ ion o
−
480% was calcula ed due o
Buildings 2025,15, 1279 8 o 15
he minimiza ion o impac s esul ing om an inc ease in ligh ing luminous e icacy om
35 o 171 lm/W (+488%). Fu he mo e, unde he p og essi e scena io, which conside ed
he deca boniza ion o he elec ici y g id o e ime, he impac s ela ed o ligh ing luminous
e icacy ell om 77 kg CO
2
e/FU o 14.8 kg CO
2
e/FU. In his case, a ela i e minimiza ion o
−520% was calcula ed o he same imp o emen o ligh ing luminous e icacy.
Buildings 2025, 15, x FOR PEER REVIEW 9 o 16
Figu e 3. Rela ion be ween luminous e icacy and he en i onmen al impac s o ligh ing in Den-
ma k. Lined black ci cles ep esen he a e age alues o each g oup, and he in e al ba s indica e
he a ia ions be ween he minimal and maximal alues.
To imp o e unde s anding o he impac s o ligh ing sys ems on he scale o he
building, Figu e 4 p esen s he GWP sco e o a case s udy in he scena ios o conside ing
a cons an and p og essi e ca bon con en o he elec ici y g id, espec i ely. Unde he
i s scena io, he a e age impac o he building was calcula ed o be 8.8 kg CO
2
e/m
2
/yea ,
wi h a a ia ion be ween 8.2 and 13 kg CO
2
e/m
2
/yea . The embodied impac s o building
ab ic and ligh ing sys em we e espec i ely equal o 4.18 kg CO
2
e/m
2
/yea and 0.15 kg
CO
2
e/m
2
/yea , con ibu ing 47% and 2% o he o e all building impac s. A he same ime,
he ope a ional impac s o he mal pu poses and ene gy used o a i icial ligh ing we e
equal o 2.8 kg CO
2
e/m
2
/yea and 1.7 kg CO
2
e/m
2
/yea , con ibu ing 32% and 19%. In his
scena io, he esul s indica ed he la ge con ibu ion o he impac s om ligh ing ene gy
consump ion, which dese es p io a en ion by he designe o educe he impac s.
Unde he p og essi e deca boniza ion o he elec ici y g id scena io, he a e age
impac s o he building we e calcula ed as equal o 6.51 kg CO
2
e/m
2
/yea . In his case,
based on he ype o ligh ing sys em employed, he impac o he building a ied be ween
6.23 and 8.16 kg CO
2
e/m
2
/yea . Rega ding he ela i e con ibu ion o he o e all impac s
o building he building ab ic, he ligh ing sys em, hea ing and en ila ion, and he en-
e gy used o a i icial ligh ing we e espec i ely equal o 64%, 2%, 24%, and 9%. E en in
his scena io, he a e age ela i e con ibu ion o ligh ing ene gy consump ion was p e-
dominan compa ed o he embodied impac s.
Figu e 3. Rela ion be ween luminous e icacy and he en i onmen al impac s o ligh ing in Denma k.
Lined black ci cles ep esen he a e age alues o each g oup, and he in e al ba s indica e he
a ia ions be ween he minimal and maximal alues.
Based on hese esul s, i can be concluded ha ligh ing luminous e icacy could be im-
p o ed by 488%, po en ially educing he GWP sco e by 480–520%. Analyzing he educ ion
in he GWP sco e due o a dec ease in he ca bon con en o he elec ici y g id, i can be ob-
se ed ha , o he lowes luminous e icacy, he impac was educed om 192 kg CO
2
e/FU
o 77 kg CO
2
e/FU (
−
250%). Meanwhile, o he highes ligh ing luminous e icacy, he
educ ion was om 40 kg CO
2
e/FU o 14.8 kg CO
2
e/FU (
−
270%). Consequen ly, imp o -
ing he g id’s ca bon con en could educe he GWP sco e by
250–270%
. These indings
sugges ha enhancing ligh ing luminous e icacy is mo e e ec i e han deca bonizing he
elec ici y g id o minimize he GWP sco e o ligh ing sys ems.
A deepe analysis o a u he classi ica ion o ligh ing luminous e icacy imp o e-
men s is p esen ed in Figu e 3, which highligh s ou g oups: low-, medium-, high-, and
e y-high-pe o mance LEDs. In he i s scena io, whe e he ca bon con en o he elec-
ici y g id emained cons an o e ime, he impac s o low-pe o mance LEDs anged
be ween 149 and 192 kg CO
2
e/FU, indica ing a a ia ion o 43 kg CO
2
e/FU. Fo medium-
pe o mance LEDs, he impac a ied be ween 65 and 128 kg CO
2
e/FU, wi h a di e ence
o 63 kg CO
2
e/FU be ween he wo s and bes cases. High-pe o mance LEDs had an
impac anging be ween 43 and 84 kg CO
2
e/FU, wi h a a ia ion o 41 kg CO
2
e/FU. High-
pe o mance LEDs showed an impac a ia ion be ween 39 and 46 kg CO
2
e/FU, indica ing
a ange o 7 kg CO
2
e/FU. Unde he p og essi e scena io, whe e he elec ici y g id’s
ca bon con en ell o e ime, he impac s o low-pe o mance LEDs anged be ween 61 and
76 kg CO
2
e/FU, wi h a di e ence o 15 kg CO
2
e/FU be ween he wo s and bes cases.
Fo medium-pe o mance LEDs, he impac a ied be ween 24 o 54 kg CO
2
e/FU, wi h a
ange o 30 kg CO
2
e/FU. High-pe o mance LEDs showed an impac a ia ion be ween
Buildings 2025,15, 1279 9 o 15
15 and 46 kg CO
2
e/FU, wi h a di e ence o 31 kg CO
2
e/FU. Las ly, o high-pe o mance
LEDs, he impac a ied be ween 15 and 21 kg CO
2
e/FU, wi h a ange o 6 kg CO
2
e/FU.
The esul s indica ed ha high-pe o mance LEDs we e he ligh ing sys em solu ion wi h
he lowes en i onmen al impac s. Howe e , i a speci ic ype o ligh ing sys em wi h
a di e en luminous e icacy mus be used, he esul s demons a ed signi ican impac
educ ions when selec ing he op imal solu ion wi hin a gi en ype o ligh ing sys em and
luminous e icacy ange.
To imp o e unde s anding o he impac s o ligh ing sys ems on he scale o he building,
Figu e 4p esen s he GWP sco e o a case s udy in he scena ios o conside ing a cons an and
p og essi e ca bon con en o he elec ici y g id, espec i ely. Unde he i s scena io, he
a e age impac o he building was calcula ed o be 8.8 kg CO
2
e/m
2
/yea , wi h a a ia ion
be ween 8.2 and 13 kg CO
2
e/m
2
/yea . The embodied impac s o building ab ic and ligh -
ing sys em we e espec i ely equal o 4.18 kg CO
2
e/m
2
/yea and 0.15 kg CO
2
e/m
2
/yea ,
con ibu ing 47% and 2% o he o e all building impac s. A he same ime, he ope a-
ional impac s o he mal pu poses and ene gy used o a i icial ligh ing we e equal o
2.8 kg CO
2
e/m
2
/yea and 1.7 kg CO
2
e/m
2
/yea , con ibu ing 32% and 19%. In his scena io,
he esul s indica ed he la ge con ibu ion o he impac s om ligh ing ene gy consump ion,
which dese es p io a en ion by he designe o educe he impac s.
Buildings 2025, 15, x FOR PEER REVIEW 10 o 16
Figu e 4. The GWP sco e o buildings in he scena ios o a cons an and p og essi e ca bon con en
o elec ici y, espec i ely, o Denma k.
Howe e , conce ning he absolu e alues o he a e age embodied impac s o he
ligh ing sys em and ope a ional ene gy consump ion in bo h scena ios, he e is an ob ious
necessi y o educe hem u he , gi en he limi alues equal o 0.3 kg CO2 e/m2/yea ha
buildings mus each unde Pa is ag eemen which Denma k is commi ed o achie e [62]
( u he mo e, he a ia ion in he building impac s o he a ious ligh ing sys ems u he
s esses he need o educe hei impac s). Fo his eason, Figu e 5 gi es de ailed esul s
o each ligh ing sys em’s absolu e and ela i e con ibu ion o imbe buildings unde he
p og essi e deca boniza ion o he elec ici y g id. Compa ing he impac s o he building
case s udy wi h he limi alue o 7.1 kg CO2 e/m2/yea [63], in 2025, he new p ojec s mus
comply wi h he Danish egula ions, o which 3% o scena ios canno each. This is mos ly
o hose cases whe e low-, medium-, and some high-pe o mance sys ems a e conside ed
as ligh ing sys em op ions. Based on hese esul s, we can conclude ha he ligh ing sys-
em is a signi ican a ge dese ing a en ion o minimize o building impac s o each he
limi a ge s and comply wi h Danish egula ions ela ed o en i onmen al impac s. In
addi ion, designe s should a oid using lamps wi h he lowe 113 lm/W luminous e icacy
as ligh ing sys em op ions, since hey signi ican ly inc ease he impac o buildings. The
implemen a ion o such op ions o ligh ing sys ems will, in consequence, equi e he
d as ic minimiza ion o ene gy equi emen s and he implemen a ion o low-ca bon
sou ces o elec ici y. On he o he hand, high- and e y-high-pe o mance LEDs a e he
ligh ing sys em solu ions ha , wi hin he amewo k o he case s udy building, could
help in eaching he limi alues. An in-dep h analysis o hese solu ions highligh ed he
ligh ing sys em esponsible o 7% and 29% o he o e all impac s o buildings. The con-
ibu ion o embodied impac s was ound o be wi hin he ange o 1% o 12.5%, while a
he ope a ional s age, i ell be ween 6% and 24%. Based on hese esul s, we can de ini-
i ely conclude ha he impac o ligh ing sys ems is signi ican compa ed o he impac s
o o he building componen s. To minimize ligh ing sys em impac s, designe s should
ocus on selec ing sys ems wi h low embodied impac s and educing he impac o hei
ope a ions.
Figu e 4. The GWP sco e o buildings in he scena ios o a cons an and p og essi e ca bon con en
o elec ici y, espec i ely, o Denma k.
Unde he p og essi e deca boniza ion o he elec ici y g id scena io, he a e age
impac s o he building we e calcula ed as equal o 6.51 kg CO
2
e/m
2
/yea . In his case,
based on he ype o ligh ing sys em employed, he impac o he building a ied be ween
6.23 and 8.16 kg CO
2
e/m
2
/yea . Rega ding he ela i e con ibu ion o he o e all impac s
o building he building ab ic, he ligh ing sys em, hea ing and en ila ion, and he
ene gy used o a i icial ligh ing we e espec i ely equal o 64%, 2%, 24%, and 9%. E en
in his scena io, he a e age ela i e con ibu ion o ligh ing ene gy consump ion was
p edominan compa ed o he embodied impac s.
Howe e , conce ning he absolu e alues o he a e age embodied impac s o he
ligh ing sys em and ope a ional ene gy consump ion in bo h scena ios, he e is an ob ious
necessi y o educe hem u he , gi en he limi alues equal o 0.3 kg CO
2
e/m
2
/yea ha
buildings mus each unde Pa is ag eemen which Denma k is commi ed o achie e [
62
]
( u he mo e, he a ia ion in he building impac s o he a ious ligh ing sys ems u he
s esses he need o educe hei impac s). Fo his eason, Figu e 5gi es de ailed esul s
