The government has given the go-ahead for a new generation of nuclear power stations. Here is a look at the plans:
What has been announced?
The government has given its verdict after a review into the future of nuclear power in the UK. It has come out strongly in favour of a new generation of privately-built plants to replace Britain's ageing reactors. The Energy Bill is also being published giving more incentives for renewable energy.
Is this a big change?
In theory there has been nothing to stop a private firm proposing to build a nuclear power station in recent years. But given the amount of investment needed, explicit government support is seen as necessary to persuade firms to do so. The government also says it will identify what it believes are the best sites for new reactors, set up a new independent body to monitor clean-up costs and streamline planning for big infrastucture projects such as nuclear plants.
Why does the government want more nuclear power stations?
It says that the existing nuclear power stations, which provide 20% of UK electricity, are scheduled to close over the next 20 years or so. They need to be replaced to ensure Britain is not over-dependent on foreign sources of energy, such as the Middle East or Russia, as North Sea oil and gas runs out, the government argues. It also believes nuclear energy will help Britain meet its carbon reduction targets and fight climate change. Business Secretary John Hutton told MPs it was also a "proven" and "affordable" way of doing so.
Can't this by done just using renewable energy?
The government is planning a huge expansion of wind farms and other forms of renewable energy but it believes there should be a mix of electricity generating methods to ensure continuity of supply.
How much will it cost and who will pay for it?
Once the cost of decommissioning and disposing of waste is factored in, nuclear can be an expensive way to generate electricity. Opponents say the clean-up bill for current plants could reach £70bn and, they add, no plant has ever been built anywhere in the world without public money. The government says the next generation of reactors will be cleaner and cost less to decommission. It insists operators will have to build and run them without subsidies. Firms will also have to pay for decommissioning. There may be tax changes "ensure a level playing field" with other forms of electricity generation. The government will bail out firms in the event of an environmental emergency and also pay for the construction of underground caverns for the storage of nuclear waste. The amount new nuclear operators will contribute towards this has yet to be decided.
Where will the new reactors be sited?
The government has not decided yet, with a review expected to report by 2009. However minister expect the new reactors to be built at or near the site of existing reactors. A report prepared for ministers last year identified 14 likely sites, with Hinkley Point, Sizewell, Dungeness and Bradwell topping the list.
What is going to happen to the nuclear waste?
The government believes it can continue to be stored above ground at temporary facilities at Sellafield, on the Cumbrian coast, until a suitable site for an underground bunker can be found. Another longer-term option might be to refurbish Sellafield's reprocessing plant or even build a new one.
What do opponents of the plan say?
Nuclear power is expensive and leaves a legacy of waste that remains dangerous for tens of thousands of years. They also say it provides terrorist targets - and that Britain can meet its energy needs, maintain energy security and tackle climate change through greater investment in renewable sources such as wind and wave power, and clean carbon technology. Greenpeace is planning a legal challenge to the government's public consultation, which it says was a sham.
What do the other parties say?
The Conservatives support nuclear power but say it should go ahead without public subsidies. The Lib Dems reject its use because of the risk of accidents and what they describe as "the long-term legacy of waste".
Will the new plants be built in all parts of the UK?
According to last year's siting report, the most likely location of new reactors is in the south of England. There are four existing reactors in Scotland but The Scottish National Party say they will use planning laws, which are devolved to Holyrood, to fight the construction of any replacements. There are currently two reactors in Wales. There are no reactors in Northern Ireland and no plans to build any.
Didn't the government announce something similar before?
Yes. In 2006 the then prime minister Tony Blair, said he believed new nuclear stations should be built. But that decision was put on hold after the consultation element of the government's energy review was ruled "seriously flawed" and "misleading" by a High Court judge, following a challenge by Greenpeace.
So when will the new plants be built?
The government is changing planning laws so that permission could theoretically be given more quickly for major infrastructure developments like power plants and airport runways. Ministers hope that the first new nuclear power station could be open by 2020. But there could yet be new legal challenges.