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Nuclear energy

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Nuclear energy

KAUNAS UNIVERSITY OF TECHNOLOGY

PANEVĖŽYS INSTITUTE

CENTRE OF LANGUAGES

TERM-PAPER

CONTENTS

The Economics of Nuclear Power 3.

Active vocabulary 6.

Exercise 1-3 6.

Answer sheet 8.

Crimes 9.

Grammar practice 10.

References 11.

The Economics of Nuclear Power

October 2004

The relative costs of generating electricity from coal, gas and nuclear plants vary considerably depending on location. Coal is, and will probably remain, economically attractive in countries such as China, the USA and Australia with abundant and accessible domestic coal resources as long as carbon emissions are cost-free. Gas is also competitive for base-load power in many places, particularly using combined-cycle pplants, though rising gas prices have removed much of the advantage.

Nuclear energy is, in many places, competitive with fossil fuel for electricity generation, despite relatively high capital costs and the need to internalise all waste disposal and decommissioning costs. If the social, health and environmental costs of fossil fuels are also taken into account, nuclear is outstanding.

External costs

The report of a major European study of the external costs of various fuel cycles, focusing on coal and nuclear, wwas released in mid 2001 – Extern. It shows that in clear cash terms nuclear energy incurs about one tenth of the costs of coal. The external costs are defined as those actually incurred in relation to health and the eenvironment and quantifiable but not built into the cost of the electricity. If these costs were in fact included, the EU price of electricity from coal would double and that from gas would increase 30%. These are without attempting to include global warming.

The European Commission launched the project in 1991 in collaboration with the US Department of Energy, and it was the first research project of its kind „to put plausible financial figures against damage resulting from different forms of electricity production for the entire EU“. The methodology considers emissions, dispersion and ultimate impact. With nuclear energy the risk of accidents is factored in along with high estimates of radiological impacts from mine tailings (waste management and decommissioning being aalready within the cost to the consumer). Nuclear energy averages 0.4 euro cents/kWh, much the same as hydro, coal is over 4.0 cents (4.1-7.3), gas ranges 1.3-2.3 cents and only wind shows up better than nuclear, at 0.1-0.2 cents/kWh average.

Fuel costs are one area of steadily increasing efficiency and cost reduction. For instance, in Spain nuclear electricity cost has been reduced by 29% over 1995-2001. This involved boosting enrichment levels and burn-up to achieve 40% fuel cost reduction. Prospectively, aa further 8% increase in burn-up will give another 5% reduction in fuel cost.

Comparing electricity generation

For nuclear power plants any cost figures normally include spent fuel management, plant decommissioning and final waste disposal. These costs, while usually external for other technologies, are internal for nuclear power.

Decommissioning costs are estimated at 9-15% of the initial capital cost of a nuclear power plant. But when discounted, they contribute only a few percent to the investment cost and even less to the generation cost. In the USA they account for 0.1-0.2 cent/kWh, which is no more than 5% of the cost of the electricity produced.

The back-end of the fuel cycle, including spent fuel storage or disposal in a waste repository, contributes up to another 10% to the overall costs per kWh, – less if there is direct disposal of spent fuel rather than reprocessing. The $18 billion US spent fuel program is funded by a 0.1 cent/kWh levy.

French figures published in 2002 show (EUR cents/kWh): nuclear 3.20, gas 3.05-4.26, coal 3.81-4.57. Nuclear is favourable because of the large, standardised plants used.

The cost of nuclear power generation has been dropping over the last decade. This is because declining ffuel (including enrichment), operating and maintenance costs, while the plant concerned has been paid for, or at least is being paid off. In general the construction costs of nuclear power plants are significantly higher than for coal- or gas-fired plants because of the need to use special materials, and to incorporate sophisticated safety features and back-up control equipment. These contribute much of the nuclear generation cost, but once the plant is built the variables are minor.

In the past, long construction periods have pushed up financing costs. In Asia construction times have tended to be shorter, for instance the new-generation 1300 MWe Japanese reactors which began operating in 1996 and 1997 were built in a little over four years.

Overall, OECD studies in teh 1990s showed a decreasing advantage of nuclear over coal. This trend was largely due to a decline in fossil fuel prices in the 1980s, and easy access to low-cost, clean coal, or gas. In the 1990s gas combined-cycle technology with low fuel prices was often the lowest cost option in Europe and North America. But the picture is changing.

Source: US Utility Data Inst. (pre 1995), Resource Data International (1995)

Note: the above data refer to fuel pplus operation and maintenance costs only, they exclude capital, since this varies greatly among utilities and states, as well as with the age of the plant. On the basis of the OECD projections opposite, capital costs in USA are 55% of total for nuclear, 45% of total for coal and 16% of total for gas. Grossing these up on this basis for 2001 gives 3.73 c/kWh for nuclear, 3.27 c/kWh for coal and 5.87 c/kWh for gas.

FACTORS FAVOURING URANIUM

Uranium has the advantage of being a highly concentrated source of energy which is easily and cheaply transportable. The quantities needed are very much less than for coal or oil. One kilogram of natural uranium will yield about 20,000 times as much energy as the same amount of coal. It is therefore intrinsically a very portable and tradeable commodity.

The fuel’s contribution to the overall cost of the electricity produced is relatively small, so even a large fuel price escalation will have relatively little effect. For instance, a doubling of the 2002 U3O8 price would increase the fuel cost for a light water reactor by 30% and the electricity cost about 7% (whereas doubling the gas price

would add 70% to the price of electricity).

REPROCCESSING & MOX

There are other possible savings. For example, if spent fuel is reprocessed and the recovered plutonium and uranium is used in mixed oxide (MOX) fuel, more energy can be extracted. The costs of achieving this are large, but are offset by MOX fuel not needing enrichment and particularly by the smaller amount of high-level wastes produced at the end. Seven UO2 fuel assemblies give rise to one MOX assembly pplus some vitrified high-level waste, resulting in only about 35% of the volume, mass and cost of disposal.

For different fuel costs (fossil fuels) or lead time (nuclear plants).DecadeAssumes 5% discount trate, 30 year life and 70% load factor. Note that the key factor for fossil fuels is the high or low cost of fuels (top portion of bars), whereas nuclear power has a low proportion of fuel cost in total electricity cost and the key factor is the short oor long lead time in planning and construction, hence investment cost (bottom portion of bars). Increasing the load factor thus benefits nuclear more than coal, and both these more than oil or gas. (OECD IEA 1992)

Active vocabulary

1. plant (decorative container ffor growing plants it) – gamykla, įšranga, agregatai

2. damage (to cause physical harm to something or to part of someone’s body) – žala, sugadinimas

3. to dispose (to arrange things or put them in their places) – sutvarkyti, išdėstyti

4. to storage (the act of keeping or putting something in a special places) – laikyti, saugoti

5. decade (a period of ten years) – dešimtmetis

6. construction (the process or method of building lage buildings, bridges, roads) – statyba, statymas

7. advantage (something that helps you to be better or more successful than others) – pranašumas, privalumas

8. energy (the physical and mental strength that makes you able to be active) – energija, jėga

9. extract (to remove an object from somewhere, especially by pulling it) –– išplėsti, ištraukti

10. opposite (as different as possible from something else) – priešingas, priešprieša

Exercise 1.

Answer the questions.

1. Why is coal economically attractive in countries such as China, the USA and Australia?

2. Why is uranium competitive with fossil fuel for electricity generation?

3. What is the main factor of electricity prices?

4. Why has been the cost of nuclear power generation dropping over the last decade?

5. What has the highest influence on the price of nuclear energy?

6. How ddid new technologies influence the term of construction period?

7. Why is nuclear energy so economic considering the expensive exploitation of nuclear power-station?

8. How can you compare uranium and coal needed to make the same amount of energy?

9. How can we increase the extraction of energy?

10. Which of disadvantages can you note as the main for nuclear power stations?

Exercise 2.

Fill in the gaps with new words.

Opposite, storage, decade, dispose, plants, construction, damage, advantages, extracted, energy.

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