Nick Clegg says coalition will be unable to subsidise nuclear energy should current uncertainty cause investors to pull away
Allegra Stratton in Mexico City
guardian.co.uk, Tuesday 29 March 2011 20.55 BST Article history
The Fukushima nuclear reactor. Following the disaster many countries are questioning the future of nuclear energy. Photograph: TEPCO/HANDOUT/EPA
Britain could join a wave of countries loosening their embrace of nuclear power in the aftermath of the Fukushima nuclear disaster in Japan, the deputy prime minister, Nick Clegg, has said.
Speaking to reporters on a trip to Mexico, Clegg said that the new uncertainty for the nuclear industry could raise its liabilities and in all likelihood entail some kind of public subsidy – which the coalition would be unable to provide.
When the Liberal Democrats joined the coalition the party was seen to drop its long-held opposition to nuclear power but retain a commitment of no new subsidies for the industry.
Any pushback over the perceived viability of nuclear energy would cause ructions in the coalition; some Tory MPs are convinced that Britain's energy mix must include nuclear power, to try to meet all the UK's energy needs while keeping a commitment to carbon emissions reductions. Some members of the Conservative benches think renewable energy sources would fail to make the weight if nuclear power were knocked out of the equation. bLib Dems believe the huge subsidies the industry can receive skew the market in favour of nuclear.
Speaking in Mexico, Clegg said: "We have always said there are two conditions for the future of nuclear power – it has to be safe and cannot let the taxpayer be ripped off. We could be in a situation now where the potential liabilities are higher, which makes it more unlikely to find private investment. There will be no rowing back on the coalition agreement, the agreement was very clear."
Clegg said the new carbon price brought in by the coalition, which will reward low-carbon technologies like nuclear and renewables, could help ameliorate the cost pressures on the nuclear industry. But he said that he was still unsure whether the industry would remain viable. Eight further nuclear plants are due for construction in the UK.
The chief nuclear officer, Mike Weightman, is managing a review of the safety of British reactors in the aftermath of the events in Japan. The interim findings are due in May.
At the moment, UK policy is based on a three-pronged portfolio approach: nuclear energy but also more renewable energy and new carbon-capture technology to mitigate the damaging environmental effects of fossil fuel-fired power plants and industrial facilities.
Despite there being few immediate parallels with Japan's reactors – which were built in an earthquake and tsunami zone – the problem for the UK government will arise if the nuclear industry as a whole becomes more insecure and therefore more expensive for investors, requiring subsidies.
The issue of nuclear power has the potential of becoming a "wedge issue" over the next few years as Lib Dems seek to distinguish themselves from their pro-nuclear coalition partners ahead of the next general election.
In Germany, the head of the ruling Christian Democratic Union party blamed the near-meltdown of the Fukushima reactors in Japan for a popular revolt against new nuclear power in Germany, which was registered at the ballot box this weekend with Angela Merkel's party partly losing to the anti-nuclear Greens in Baden-Württemburg.
In Hamburg, Berlin, Cologne and Munich 200,000 protesters took to the streets demanding the closure of all 17 of Germany's nuclear reactors. Merkel has already had to act. She declared a three-month moratorium on a decision about whether to extend the life of the existing reactors.
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Beginner's guide: How nuclear power works
Is nuclear power the answer to the energy crisis? Ian Sample explains how it works - and how we get the awful side-effects of bombs and waste
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Ian Sample
The Guardian, Wednesday 30 April 2008
Article history
Nuclear power
The world's first large-scale nuclear power plant opened at Calder Hall in Cumbria, England, in 1956 and produced electricity for 47 years.
Nuclear power is generated using uranium, a metal that is mined as an ore in large quantities, with Canada, Australia and Kazakhstan providing more than half of the world's supplies.
Nuclear reactors work in a similar way to other power plants, but instead of using coal or gas to generate heat, they use nuclear fission reactions. In most cases, heat from the nuclear reactions convert water into steam, which drives turbines that produce electricity.
There are different kinds, or isotopes, of uranium, and the type used in nuclear power plants is called uranium-235, because these atoms are easiest to split in two. Because uranium-235 is quite rare, making up less than 1% of natural uranium, it has to be enriched until the fuel contains 2-3%.
Inside a nuclear reactor, rods of uranium are arranged in bundles and immersed in a giant, pressurised water tank. When the reactor is running, high-speed particles called neutrons strike the uranium atoms and cause them to split in a process known as nuclear fission. The process releases a lot of energy and more neutrons, which go on to split other uranium atoms, triggering a chain reaction. The energy heats up the water, which is piped out to a steam generator.
To make sure the power plant does not overheat, control rods made of a material that absorbs neutrons are lowered into the reactor. The whole reactor is encased in a thick concrete shield, which prevents radiation escaping into the environment.
In Britain, nuclear power stations provide 19% of our electricity and account for 3.5% of our total energy use. All but one of those reactors are due to close down by 2023.
Some groups oppose nuclear power stations because they produce radioactive waste and could release radioactive material if there was an accident. But nuclear power plants do not release greenhouse gases, which cause coal and gas-fired power plants to contribute to global warming. Without nuclear power stations, UK's carbon emissions would be 5% to 12% higher than they are.
In 1957, the world's first nuclear power accident occurred at Windscale in west Cumbria. A fire in the reactor caused a release of radioactivity, which led to a ban on milk sales from nearby farms. The site was later renamed Sellafield. Modern reactors are designed to shut down automatically. The worst nuclear power accident in history took place in Chernobyl in 1986 when a reactor there exploded, killing tens of people instantly and exposing hundreds of thousands more to radiation.
In January, the government reaffirmed its plans to expand nuclear power in Britain to help it meet stringent targets to reduce carbon dioxide emissions.
Nuclear weapons
There are two main types of nuclear weapon: atomic bombs, which are powered by fission reactions similar to those in nuclear reactors, and hydrogen bombs, which derive their explosive power from fusion reactions.
The first atomic bomb was produced at Los Alamos National Laboratory in America under the Manhattan Project at the end of the second world war. An atomic bomb uses conventional explosives to slam together two lumps of fissionable material, usually uranium-235 or plutonium-239. This creates what is known as a critical mass of nuclear material, which releases its energy instantaneously as atoms inside it split in an uncontrolled chain reaction.
Atomic bombs unleash enormous shock waves and high levels of neutron and gamma radiation. In atomic bombs, uranium is enriched much more than fuel, to about 85% uranium-235.
On August 6 1945, an atomic bomb called Little Boy was dropped on the Japanese city of Hiroshima, followed three days later by another, called Fat Man, on Nagasaki.
Hydrogen, or thermonuclear bombs, work in almost the opposite way to atomic bombs. Much of their explosive power comes from fusing together hydrogen atoms to form heavier helium atoms, which releases far more energy than a fission bomb. Two types, or isotopes, of hydrogen are used - deuterium and tritium. A deuterium atom is the same as a hydrogen atom, except the former has an extra neutron in its nucleus. A tritium atom has two extra neutrons.
A hydrogen bomb has a built-in atomic bomb, which is needed to trigger the fusion reaction. Hydrogen bombs have never been used in war and are thousands of times more powerful than atomic bombs.
The first test of a hydrogen bomb was at Enewatak, an atoll in the Pacific Ocean. It released a three mile-wide fireball and a mushroom cloud that rose to nearly 60,000 feet, destroying an island in the process.
Nuclear waste
One of the biggest problems the nuclear industry faces is what to do with the radioactive waste it produces. Some of it will remain radioactive and hazardous for hundreds of thousands of years.
High-level waste is the most dangerous because it can melt through containers and is so radioactive it would be fatal if someone was near it for a few days. This type of waste makes up just 0.3% of Britain's total volume of nuclear waste, which is mostly waste from spent fuel rods. The largest amounts of radioactive waste are made up of nuclear fuel cases, reactor components and uranium.
Today, high-level waste is dealt with by cooling it in water for several years and then mixing it into a molten glass, which is poured into steel containers. These canisters are then stored in a concrete-lined building.
This is only a temporary measure, though. Scientists know that eventually they need to find a way of storing nuclear waste safely for thousands of years. Some countries, such as America and Finland, plan to store nuclear waste in deep underground bunkers. For this to be safe, scientists have to be sure the material could never leak out and contaminate water supplies or rise up to the surface.
Britain already has more than 100,000 tonnes of higher activity radioactive waste that needs to be stored. Large amounts of low-level waste are already stored in concrete vaults in Drigg in Cumbria. Other plans for disposing of nuclear waste have included dumping it at sea and blasting it into space.
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