Environmental impacts of the production of electricity
6. Methodology of the study: the LCA The methodology used for the estimation of the environmental impacts of the energetic systems considered is the Life Cycle Assessment (LCA). This is an internationally recognized –ISO 14.040– environmental tool used to identify in an objective and rigorous way all the environmental impacts of a product, process or activity from cradle to tomb, that is to say, along all phases of its life cycle –from the extraction of raw materials needed for its elaboration until its final management as a waste–. The study has analysed the following life cycle stages of the electrical generation systems: ¾ Obtain the fuel (mining and extraction). ¾ Treatment of the fuel (preparation). ¾ Transport of the fuel. ¾ Construction of the plant (works and equipments). ¾ Running the central (Production of electricity) Next figure shows life cycle scheme analysed for the coal system:
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C O2
PST
C H4
H C l, H F
N Ox
Fe, Al , S i
CO
Me tal e s p esa do s
S u lf a to s
Lo do s
C e n iza s
E sc oria s
C lo ru ro s
C e m e nto
U tiliza ción d e te r re no
En e rgía
A re na
Ace ro
C o n str ucc i ón de la C e n tr al
M a ter ial e s a gr e ga do s
E n er gía
A g ua
C a lo r r esid u al kW h
C om b u sti ón c a rb ón
T2
Lo do s
A g ua
S Ox
C o m b u stib le
E n er gía
C O2
C al iza
T2
T ra ta m i e nto (la v ad o )
T1
S usta n cia s d isu el ta s
C O2
En e rgía
S u lf a to s
E sté ril e s d e m i na
Im pa cto p aisaj ístico
U tiliza ción d e l te r re no
E x tra c ci ón
En e rgía
P lu via le s
Po l vo
E n er gía
E s cu r rido s
C al iza
C O2
S IS T E M A E N E R G É T IC O D E L C A R B Ó N
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Figure 3: Analysis of coal energy system
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