Quick Fire Science: Nuclear Power
This week, nuclear expert Mycle Schneider, formerly an adviser to the French and German governments has said that he's deeply worried about contaminated cooling water leaking from tanks at the site of the Fukushima nuclear reactors.
- Huge amounts of energy can be released by joining or fusing small atoms together to make larger atoms, or by splitting apart larger atoms like uranium.- In nuclear reactors, atoms such as Uranium 235 and Plutonium 239 are bombarded by neutrons which causes them to split in two, a process called fission.- When atoms undergo fission, they often release more neutrons, which can go on to hit another atom, creating a chain reaction.- A kilogram of uranium in a nuclear reaction can release more energy by fission than 10 000 tonnes of coal, gas or oil, and all without releasing any greenhouse gasses.- In a nuclear bomb, all of the energy from several kg of uranium or lutonium are emitted within a single microsecond, creating an immensely destructive burst of energy.- The first controlled release of nuclear energy was in a reactor built in 1942 under the stands in a chicago university american football stadium. But it wasn't producing power, just plutonium to build America's second nuclear bomb.- The first commercial nuclear power station was Calder Hall in cumbria . It was built in 1956 and generated 60 megawatts of power.- Unfortunately many of the atoms left over after fission are unstable and can release some of their remaining energy over days and years in the form of high energy particles and gamma rays, known as radiation.- This radiation can damage the DNA in cells which can cause cancer, or in very large doses radiation sickness.- On average less than a third of 1% of your annual radiation exposure is due to nuclear bombs and nuclear power. Between a third and a half of your exposure is due to medical procedures such as X-rays and the rest is due to natural radiation.- Today in the uk 19% of electricity is produced by nuclear power compared to 4.6% by renewables and the percentage is dropping as older plants are being decommissioned.- The last nuclear power plant to be built in the UK was Sizewell B completed in 1995.