Opinion
Facts don't affirm popular belief
By Benjamin K. Sovacool (China Daily)
Updated: 2011-03-23 15:13
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Many people are again presenting nuclear power as a solution to the world's energy demands because of the constraints associated with coal and the fear of oil prices shooting through the roof, and because the reality of global warming has started to hit home.
But can nuclear power provide what we are all looking for: a reliable, affordable, sustainable, secure and now low-carbon source of electricity?
When the full nuclear fuel cycle is considered - not only reactors but also uranium mines and mills, enrichment facilities, spent fuel repositories and decommissioning sites - nuclear power proves to be one of the costliest sources of energy. Nuclear plants are capital intensive and the high capital costs result in higher charges by electricity generators. This either ends up with high costs for customers, or significant government funds being expended on subsidies, or both.
A study of construction costs of nuclear power facilities across five countries has found that quotes by industry were unreliable, conservative and that construction was subject to costly project overruns which sometimes doubled the cost of building the plant.
Since most Asian nuclear programs are new, decommissioning costs for Asian governments are largely unknown. Historical data from the United States and the United Kingdom indicate huge decommissioning costs of $300 million to $5.6 billion per nuclear power facility. Assessment of decommissioning by the US General Accounting Office show that decommissioning costs have exceeded plant revenue by more than $4 billion.
Moreover, nuclear power is reliant on uranium availability and uranium prices, like oil and natural gas, and highly volatile. This means uncertain uranium prices can have a grave impact on plant operating costs. Such price movement is hard to anticipate when some of the countries, responsible for more than 30 percent of the world's uranium production, are politically unstable.
To plan for long-term energy solutions, fuel availability needs to be assessed beyond 2020, when future plants in Asia will be operational. The International Atomic Energy Agency expects that primary supply of uranium (all newly mined and processed uranium) will meet only 4 to 6 percent of total demand in 2025, and secondary supply (highly enriched uranium, enriched uranium inventories, mixed oxide fuel, reprocessed uranium and depleted uranium tails) will meet 8 to 11 percent of the world demand.
The implication is clear: a huge shortfall is likely to exist between uranium supply and demand. Even on optimistic assumptions of fuel availability, global reserves of uranium will only support a growth in nuclear power of 2 percent and be available for 70 years.
Furthermore, the nuclear fuel cycle involves some of the most dangerous elements known to humankind. These elements include more than 100 dangerous radionuclides and carcinogens such as strontium-90, iodine-131 and cesium-137, which are the same toxins found in the fallout of nuclear weapons.
In addition to questions about the safe handling of such elements, the nuclear fuel cycle presents numerous other environmental risks.
Nuclear energy is highly water intensive. Nuclear plants use 25 to 50 percent more water per unit of electricity generated than fossil fuel plants with equivalent cooling systems. That's why during periods of drought many nuclear facilities either cannot operate or induce water shortages. The average US plant operating on an open-loop cooling system withdraws 216 million liters of water and consumes 125 millio n liters every day.
Nuclear plants and uranium mining contaminate water, too, and the methods used to draw water and exclude debris through screens kill marine and riparian life, setting in place a destructive chain of events for ocean/river systems.
About 10,000 tons of spent nuclear fuel is discharged each year from existing nuclear facilities, because nuclear plants convert most of their fuel to waste (only 15 percent can be reprocessed).
On average, a plant produces 30 tons of waste a year and this waste can be radioactive for up to 250,000 years. The lowest available estimate for the storage of 1 ton of nuclear waste is $35,000 a year, so that's a minimum cost per facility of over $1 million a year for the conceivable future.
The main problem caused by nuclear waste however is where to store it, since even nuclear waste processed in storage casts will take at least 10,000 years to reach levels of radiation considered safe for human exposure. With five waste streams that can contaminate and degrade land, suitable sites for storage are hard to find.
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But when emissions from uranium mining, milling and spent fuel conditioning are added to the emissions associated with plant construction, operation and decommissioning, a typical reactor emits about 66 grams of carbon dioxide equivalent for every kilowatt-hour of electricity produced.
This figure, which is more than any single source of renewable electricity, is likely to increase significantly as more energy intensive uranium enrichment is required once high quality uranium ores are exhausted. The Oxford Research Group has estimated that by 2050, nuclear electricity will have the same carbon footprint as natural gas.
In addition to the catastrophes at Three Mile Island and Chernobyl, there has been at least one nuclear incident and on average $332 million awarded in damages every year for the past three decades.
Although the nuclear industry says it has learned from its mistakes and that new technology and strict supervision have made plants much safer, 57 accidents have occurred since the Chernobyl disaster in 1986, with two-thirds of them taking place in the US.
Planning our energy future is difficult. Nuclear, renewable and fossil fuel-based energy sources all have trade-offs - security versus reliability, affordability versus carbon emissions, and capital intensity versus environmental impact, to name a few. And policymakers everywhere can never be too cautious in building nuclear power plants.
The author is an assistant professor at the Lee Kuan Yew School of Public Policy at the National University of Singapore.
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