In January, the German Öko-Institut (Institute for Applied Ecology) released an updated version of its November 1997 paper, “Comparison of Greenhouse-Gas Emissions and Abatement Cost of Nuclear and Alternative Energy Options from a Life-Cycle Perspective”, first presented at the CNIC Conference on Nuclear Energy and Greenhouse-Gas Emissions held in Tokyo.
(642.5752) WISE Amsterdam - The paper addresses the two main arguments currently being used to good effect in much of the international mainstream media by the nuclear industry’s publicists and government spin doctors - that it is supposedly ‘free’ of CO2 and inexpensive - by presenting the results of life-cycle cost and emission analyses of the various energy systems of currently available technologies. The results are compared to other published findings and also demonstrate the cost-effectiveness of CO2 abatement (reduction) in the electricity sector.
Where the claims on nuclear power’s ozone friendliness are concerned, the Institute’s scientists looked not only at what happens at the end point, the nuclear power plant, but have also considered the processes that go into the production of nuclear electricity - ore mining and processing, uranium enrichment, fuel fabrication etc. - and which represent the upstream fuel cycle. The downstream fuel cycle, which involves post-plant activities like the processing and storage of nuclear wastes, is also considered in addition to the energy used in the production of the necessary materials - steel, concrete and other materials required for the construction of nuclear power plants - for use in both the up and downstream fuel cycles. Energy used for up and downstream cycles is partly produced by fossil fuel energy causing greenhouse gas emissions, other gases are also released as a result of the chemical reactions during the processing of construction materials for example. The inclusion of all these elements means that the analysis comprises of the whole life cycle, which provides a more complete picture.
The paper does also point out that nuclear is not the only energy source that requires up and downstream activities before electricity can be generated in a plant - fossil fuels and biomass need to be extracted, processed, converted and transported as well.
Comparisons
In order to provide an accurate comparison of GHG emissions from different energy processes, the Institute’s researchers tracked each step in the life-cycle of energy technologies and all activities that directly or indirectly emit GHGs given that emissions and other environmental impacts can occur during any of the steps in the processes making up the cycle. The three levels of impacts considered are direct impacts from the operation of processes, indirect impacts from auxiliary input to these processes (including transports), and indirect impacts from manufacturing materials used during the construction of all processes. Since the levels are interlinked, the life-cycle analysis also considers the interactions between all processes.
The Öko-Institut used the GEMIS (Global Emission Model for Integrated Systems) computer model, which is continuously updated and expanded, to compile the huge variety of data that has been collected.
Nuclear Results
The GEMIS model compiled data on nuclear plants, and their whole life cycles as described previously and according to that data calculated around 31 grams of CO2 per kilowatt hour (kWh) of electricity (el) generated in Germany. The other GHGs emitted along the nuclear life cycle contribute a further 33 grams of CO2 equivalents per kWhel. For a standard sized nuclear plant (1250 MW) in Germany, the indirect emissions total around 250,000 tons per year. Other international studies have shown higher figures, up to 120 g/kWhel.
In comparison with the other ten energy sources whose life-cycle emissions were calculated by GEMIS, nuclear had the fifth highest level of CO2 emissions per kilowatt-hour of electricity generated. The highest was standard coal at around 900 g/kWhel; coal cogeneration (combined heat and power) was next at around 460 g/kWhel, then gas combined cycle cogeneration and then photovoltaic (solar) with around 120 g/kWhel. Solar power comes in at such a high level because of its upstream cycle.
The net CO2 emissions from electricity generated from gas-fired ICE (internal combustion engine) cogeneration is actually lower than that of electricity from nuclear plants, as is electricity efficiency and electricity from other renewable sources.
Where other GHGs are concerned (mostly nitrogen oxide and methane), the life-cycle emissions of nuclear remains relatively unchanged but increases are seen with coal and natural gas systems.
Overall, renewable electricity and efficiency have lower GHG gas emissions than nuclear electricity. Small-scale gas cogeneration plants have similar levels or emissions to nuclear while biogas-fired cogeneration has far lower emissions than nuclear.
Costs
There are two types of costs to consider: generation costs and CO2/GHG reduction costs.
Generation costs are the specific costs associated with generating one kWh of electricity (without taking into account external costs). GEMIS considered a broad range of data including investment, operating and decommissioning costs, operating time and lifetimes. Depending on the various parameters, the costs of generating nuclear electricity ranges from 4.6 to 6.5 Euro cents (year 2000 values) per kilowatt-hour for current reactor designs, with GEMIS data for Germany at 5.3 Euro cents per kilowatt-hour of electricity. Electricity efficiency, gas CC (combined cycle) cogeneration, coal cogeneration and standard coal cost less per KWh of electricity.
More relevant to the discussion is how much CO2 or GHG reduction or avoided emissions can be reached per Euro cent invested. Taking a standard coal plant as reference point, electricity efficiency, biogas-fired ICE, gas CC cogeneration and coal cogeneration, score better than nuclear power. Therefore the use of an intelligent mix of efficiency measures, renewable energy sources and fossil (cogeneration) alternatives would in fact reduce GHG reduction costs by three to four times compared to nuclear power.
Contact: Uwe R. Fritsche, Coordinator, Energy & Climate Division, Öko-Institut (Institute for applied Ecology), Darmstadt Office, Rheinstr. 95, D-64295 Darmstadt, Germany
Phone: +49-6151-8191-40 (secret.), -24 (direct)
Fax: +49-6151-8191-33
E-mail: u.fritsche@oeko.de
Website: www.oeko.de
 |
 |
 |
 |
|
 |
 |
 |
 |