terça-feira, janeiro 13, 2009

6 Reasons Why Nuclear Power Can't Save Us

The following is an excerpt from The Transition Handbook: From oil dependency to local resilience by Rob Hopkins.

1. Length of time to come on stream

Commissioning and building new plants is a time-consuming business (at least twenty years), so they would have little or no impact on cutting emissions over the next twenty years, nor build any resilience in the face of peak oil.

2. Insurance

The insurance industry refuses to underwrite nuclear power, a gap it looks like the government will have to fill, resulting in a huge invisible subsidy for nuclear power.

3. Waste

Nuclear waste is a huge problem. The UK alone has 10,000 tons of nuclear waste, a pile which will increase 25-fold when the existing plants are decommissioned, with no solution in sight other than deep burial. The disposal of nuclear waste requires a great deal of embodied energy, including that in the materials used to maintain the disposal facilities (i.e. concrete and steel). It is often said that nuclear waste has a half-life of 100,000 years…it is worth remembering that Stonehenge was built only 4,000 years ago.

A society in energy descent, dependent on local, lower embodied energy building materials, will struggle to maintain nuclear waste sites with cob blocks and straw bales.

4. Cost

A new programme of nuclear power would be staggeringly expensive. Amory Lovins has calculated that 10 cents invested in nuclear energy could generate 1kwh of nuclear energy, 1.2- 1.7kwh wind-power, 2.2-6.5kwh small co-generation, or 10kwh of energy efficiency. Also, having sufficient money to invest so unwisely assumes an economy which is still growing, an increasingly unlikely prospect.

5. Peak Uranium

At the moment, there are about 60 years’ worth of uranium left. However, if electricity generation from nuclear grows steadily, this figure will fall, to the point where if all the world’s electricity were generated with nuclear, we’d have around 3 years supply left.

6. Carbon Emissions

Nuclear is often said to be a carbon-free way of generating electricity. While that may be true for the actual generation, it is not when the entire process is looked at. The mining, processing, enrichment, treatment and disposal all have significant impacts, equivalent to around one-third those of a conventional- sized gas-fired generating plant.