Abstract
In the absence of direct sources of greenhouse gas (GHG) emissions (i.e. combustion), other
sources of emission become dominant in so-called ‘emission-free’ power plants. In this study
the indirect GHG emissions, related to construction of nuclear plants, windfarms and photo-
voltaic plants, are estimated with two dierent types of life-cycle assessment. The process-
chain analysis divides an investment good into its material components (tons of material) and
then unravels the entire production process of each material product. The energy required in,
and the GHG emissions related to, the construction of the power plant are obtained by inte-
gration over all process steps and summation over all material products. The input/output
analysis looks at the dierent economic sectors called on in the construction of the power
plant. The sectors that represent a part of the total cost of the power plant are responsible for
the amount of energy used (and the corresponding GHG emissions) to deliver their final
product. A result is provided by detailed analysis of all relevant sectors and fitting them into
the construction phase. Using similar techniques, energy use and GHG emissions related to
maintenance and demolition, including storage of nuclear equipment, can be quantified. For
construction, maintenance and demolition of these power plants, following orders of magnitude
are obtained: nuclear: 40kJ prim /kWh el , 3g CO2 /kWh el ; wind(coast): 120kJ prim /kWh el , 9g CO2 /kWh el ;
wind(inland): 350kJ prim /kWh el , 25g CO2 /kWh el ; PV(1998): 3000kJ prim /kWh el , 130g CO2 /kWh el ;
PV(near future): 1500kJ prim /kWh el and 60g CO2 /kWh el . # 2000 Elsevier Science Ltd. All rights
reserved.
Keywords: Greenhouse-gas emissions; Electricity generation; Investment goods; Life-cycle assessment