The government says it has identified eight potential sites in England and Wales for new nuclear power stations by 2025.

Where are the proposed locations?

The following are earmarked for possible new nuclear plants: Bradwell in Essex; Hartlepool; Heysham in Lancashire; Hinkley Point in Somerset; Oldbury in Gloucestershire; Sellafield in Cumbria; Sizewell in Suffolk and Wylfa on the Isle of Anglesey. All are the sites of existing or former nuclear plants. Developments will only get the go-ahead following consultation with residents and environmental groups and when planning permission is given.

Which sites have been ruled out?

Dungeness in Kent and both Braystones and Kirksanton in Cumbria have been ruled out for environmental reasons. As the Scottish government is opposed to future nuclear expansion, existing plants north of the border - Hunterston and Torness - are not on the list.

Why does the UK need new plants?

The last Labour government came out strongly in favour of a new generation of privately built plants to replace Britain's ageing reactors and the coalition government has broadly endorsed this policy. Existing nuclear power stations, which provide 20% of UK electricity, are scheduled to close over the next 20 years or so. Ministers believe they need to be replaced by 2025 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. Nuclear energy is also seen as a way of helping Britain meet its carbon reduction targets and fight climate change.

Can't this be done by 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?

Given the amount of investment needed, some experts believe explicit government support will be necessary to persuade firms to get involved. Opponents say the clean-up bill for current plants could reach £70bn and no plant has ever been built anywhere in the world without public money. The government says the next generation of reactors will cost less to decommission but insists operators will have to build and run them without subsidies and pay for decommissioning. A number of firms are believed to have expressed interest but industry has warned uncertainty over the planning regime and electricity market reform would deter them.

What is going to happen to the nuclear waste?

The government's assumption is that radioactive waste will be stored at the site where the waste is produced until a suitable site for an underground bunker becomes available or alternative arrangements are made such as a central storage facility, if a site can be identified and the necessary regulatory and planning permissions obtained.

Is future expansion politically contentious?

The government supports future nuclear expansion but the Lib Dems are far less enthusiastic than their Conservative partners. The coalition agreement gives Lib Dem MPs the scope to abstain in future Commons vote on nuclear power. However embarrassing any revolt might be over the issue, it is unlikely to be a real thorn in the side as Labour supports future nuclear expansion. While there are concerns over how it will be paid for, the nuclear industry employs more than 40,000 people and new plants could provide valuable job opportunities.

What do opponents 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.

So when will the new plants be built?

The government wants to streamline planning laws so that permission could theoretically be given for the new plants much more quickly than in the past. Ministers and business groups hope that the first new nuclear power station could be open by 2020, with the bulk of the new reactors operating by the middle of the following decade. But there could yet be new legal challenges which slow the process down.