December, 2006 Page: 28
Nuclear power is not as clean, green or cheap as its proponents would like us to think, writes Dr Mark Diesendorf.
With growing international and national concern about global climate change from human-induced greenhouse gas emissions, the nuclear power industry has attempted to change the image of its product into that of an energy source that is 'clean, green and cheap'. In reality, all the serious problems that worried us about the nuclear industry in the 1970s and 1980s are either unchanged or have become worse.Nuclear wastes and economics
Not a single country has built a facility for the long-term management of high-level nuclear wastes. The US, said to be the most advanced in this regard, is building a waste repository at Yucca Mountain, Nevada. So far, costs have amounted to US$8-10 billion ($10.2-12.7 billion) and the estimated complete life-cycle cost is $72 billion in today's prices. In July 2004, the US Court of Appeals rejected the EPA's radiation release regulations for Yucca Mountain, ruling that public health protections extending out 10,000 years post-burial are insufficient and ordering that regulations must extend hundreds of thousands of years into the future. In 2005, a scandal emerged about the falsification of safety data in relation to groundwater modelling. This is as good as it gets.
Now that several countries have created competitive markets for electricity, it is clear that the cost of nuclear electricity is even higher than previously estimated. In the UK, nuclear power was propped up through the 1990s by the Fossil Fuel Levy, which reached £1.3 billion ($3.2 billion) per year. In the US, not a single new nuclear power station has been built since the 1970s, despite accumulated subsidies estimated at about $126 billion throughout the past 50 years. An expert multidisciplinary pro-nuclear group from the Massachusetts Institute of Technology has estimated that electricity from a new nuclear power station would cost US6.7-7.5 cents per kilowatt-hour (9-10 c/kWh), not counting subsidies. That is more expensive than wind power at 7.5-8.5 c/kWh.
CO2 and the alternatives
Every step (except reactor operation) in the nuclear fuel chain burns fossil fuels and hence emits CO2. When high-grade uranium ore is used, total CO2 emissions are quite small, but there are only a few decades of high-grade uranium left. With low-grade ore, at least 10 tonnes have to be mined and milled, using fossil fuels, to produce just 1 kg of uranium oxide (yellowcake). Then CO2 emissions If carbon pricing were introduced... most of these genuinely clean technologies would romp in ahead of nuclear power and so-called 'clean coal: 77 become significant. In response, the nuclear industry cites a report by Swedish utility, Vattenfall, which has not been published and is not available on the internet. Only a summary, that does not reveal most of the assumptions, is accessible. It is poor science to cite a report that is unavailable to the public.
Clearly, nuclear power is not clean, green or cheap and is not an answer to the problem of human-induced climate change. We already have a large portfolio of technologies for cutting CO2 emissions: efficient energy use, solar hot water, natural gas, wind power and bioenergy.
More expensive, but developing rapidly, are solar electricity and hot dry rock geothermal. If carbon pricing were introduced - together with high standards of energy efficiency in buildings, equipment and appliances - most of these genuinely clean technologies would romp in ahead of nuclear power and so-called 'clean coal'.
Dr Mark Diesendorf is from the Institute of Environmental Studies at the University of New South Wales.
and now for the other side of the debate...
Nuclear power could be the answer to Australia's dependence on coal, writes Associate Professor Martin Sevior
The current best estimate of the science tracking human induced global warming is that global CO2 emissions must be reduced to 60 per cent of their 1990 levels by 2050 in order to keep the global temperature increase below 2°C.
Australia has the OECD's highest emissions of CO2 per capita, largely because of our reliance on coal to provide cheap and reliable electricity. Indeed, electricity demand has been growing annually at 3.7 per cent during the past five years. Our challenge is to find ways to grow economically while reducing CO2 emissions, which is particularly daunting when faced with the expected decrease in world supplies of oil and natural gas during the next 50 years.
We need essentially zero emission large scale energy generation technology. One option is to use nuclear power to provide baseload electricity. Unlike renewable energy sources, nuclear power is a `drop in' replacement for coal-supplied electricity, as it does not fluctuate on a daily or a seasonal basis. Modern life-cycle analyses show that, when used at world's best practice, the energy investment required to build a nuclear power station is typically repaid in a couple of months' operation. The backend of waste disposal and decommissioning is repaid in a similar period.
The fuel is abundant and contributes less than 10 per cent of the cost of power produced from nuclear reactors. While there are some CO2 emissions associated with uranium mining, the lowest grade mine currently in operation, Rossing in Nambia, produces uranium that provides about 400 times more energy than the energy cost of mining, with a commensurately small contribution to CO2 outputs.
All up, these life-cycle analyses show nuclear power has similar emissions to wind power and less than one per cent of those of fossil fuel generators.
What does it cost?
The cost of generating nuclear power can be separated into the costs of construction, operation, waste disposal and plant decommissioning. Construction costs are difficult to quantify but dominate the equation. The problem is that proposed third generation power plants are claimed to be both substantially cheaper and faster to build than current plants. Westinghouse claims its Advanced PWR reactor, the AP1000, will cost US$1,800 ($2,320) per kW for the first reactor and fall to $1,545 per kW for subsequent builds.
It also claims these will be ready to switch on three years after first pouring concrete. Compare this to second generation plants in the US, which had construction costs up to $6,420 per kW and generally took more than five years to complete.
The reasons for the high costs in the 1980s are well understood: design changes after the Three Mile Island accident; duplicate licensing for both plant building and operation; and lack of economies of volume.
Operating costs are much easier to quantify and are independently verified. Since 1987, the cost of producing electricity has decreased from 3.63 cents per kilowatt-hour (c/kWh) to 1.68 c/kWh in 2004, with plant availability increasing from 67 per cent to more than 90 per cent. This includes a charge of 0.15 cents per kW/hr to fund the disposal of radioactive waste and for decommissioning the reactor.
If we assume a seven per cent interest rate and four-year construction period, the cost of electricity production for plants that cost respectively $1.26 billion, $1.8 billion and $2.5 billion would be US2.8 c/kWh, 3.1c and 3.9c. Electricity from eastern Australian coal costs US2-4 c/kWh and wind power about US5.5-7 c/kWh. There is a credible case for nuclear power in Australia. We should build up the intellectual infrastructure needed to deploy it while closely watching the new wave of building elsewhere in the world.
Martin Sevior is Associate Professor at the School of Physics at the University of Melbourne. His complete study is at http://nuclearinfo.net
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