Atomic power was at the heart of the Government's Energy White Paper yesterday. Lindsay Jennings looks at the debate over Britains reliance on nuclear fuel

TO some, it is seen as a wasteful energy system of the past. To quote John Sauven, the director of the environmental group Greenpeace, for example, putting nuclear power at the centre of Britain's future energy needs is like "an obese person taking up smoking to lose weight".

Yet, as the Government unveiled its Energy White Paper yesterday, it became clear that nuclear power is still seen as the answer to Britain's energy needs.

While environmental campaigners champion alternatives in the renewable energy revolution - from wind farms to solar panels - nuclear power, says the Government, has been chosen for the very way it will be able to help Britain meet her carbon emission targets.

Sir Bernard Ingham, secretary of lobby group Supporters of Nuclear Energy, says of environmental campaigners: "I think they are throwing away the only method of generating electricity which produces next-to-no greenhouse gases."

But with all but one of the country's nuclear power stations - which provide 20 per cent of the country's energy needs - due to close by 2023, where will future nuclear provision come from?

We look at some key questions and answers surrounding the atomic debate.

How does nuclear power work?

When nuclear power first burst onto the scene about 50 years ago it was touted as the miracle answer to the world's energy needs.

Nuclear power uses uranium which is found in rocks around the world. The two largest producers of uranium are Canada and Australia.

Uranium dioxide pellets are produced which are then encased in long metal tubes to form fuel rods which are sealed and assembled in clusters for use in the core of the nuclear reactor.

Nuclear reactors then produce electricity by heating water to make steam. The steam is used to drive turbines that generate electricity.

One nuclear fuel pellet, which is about 2cm long, can produce the same amount of electricity as 1.5 tons of coal.

Does nuclear power create greenhouse gases that will contribute to global warming?

Nuclear reactors are similar to other thermal power stations in that burning coal or gas also produces steam which drives turbines. But nuclear reactors emit little carbon dioxide and less greenhouse gases which contribute to global warming.

Finland's parliament has approved the construction of a new nuclear power station which it hopes will help the country to meet its greenhouse gas emission targets. It will be the first to be built in western Europe since 1991.

What happens to the waste products from nuclear reactors?

Used fuel from a nuclear reactor is stored to allow most of the radioactivity to decay. It is then either reprocessed to recover the reusable portion or disposed of directly as waste. One of the questions that will be asked is where can we put that waste, which remains dangerous for centuries.

Currently, nuclear facilities are decommissioned after the end of their operating lives. All nuclear materials, machinery and plant are removed and the site is returned to a state where it can be used for a new purpose.

How many nuclear power stations are there in Britain?

There are currently 16 nuclear power plants in Britain, half operated by British Nuclear Fuels (BNFL) and the other half by British Energy.

All power stations run by BNFL will close by 2010 and those run by British Energy will close by 2023. The power stations have outlived their 20-25 year life expectancy.

This will leave one power plant in Suffolk running until 2035. There has not been any building of nuclear power stations in Britain in more than ten years.

The Government is currently being advised that Britain needs to build further nuclear power stations if it is to meet greenhouse gas emission targets.

What's wrong with building more power stations?

Building a nuclear power station is not simple even when permission has been given.

A report commissioned by Greenpeace said the average nuclear power station costs up to three times more than expected and takes four years longer to build than planned.

"We can't even build football stadiums on time or on budget. If you look at any big infrastructure projects you have similar problems," says Mr Sauven of Greenpeace.

"We do agree that we need new efficient combined heat and power stations to replace existing nuclear power stations. But we also need to deal with the bigger picture of cutting energy demand.

"If you just phased out energy inefficient lightbulbs then you could close down two power stations."

The campaign group also believes that more reactors would create tens of thousands of tons of waste, which would remain dangerous for up to a million years.

Why can't we rely on other energy sources, such as coal, gas or wind power?

By 2015, the amount of electricity from renewable energy will triple to 15 per cent, with particular focus on offshore wind power. Tidal power could also make a significant contribution and potentially provide up to five per cent of the country's electricity demand.

But the Government believes that renewable energy alone will not be enough to provide an answer to Britain's energy needs - although Friends of the Earth argue renewable resources could generate more than half our electricity needs by 2025.

The Government also says that wind farms are not popular with everyone. Some say they ruin the landscape while others worry about the effect on wildlife.

Our coal stocks are dwindling with as little as 30 years of supplies left and coal also emits huge quantities of carbon dioxide which affects global warming. Our gas provisions - although a considerably cleaner fuel than oil - are running out in the North Sea and if Britain stays with gas stations it will rely more and more on other countries, such as Russia and Algeria, for its fuel, which could prove expensive.

What happens now?

The Government says it has reached a preliminary decision to allow energy companies to invest in nuclear power. It would be up to them to initiate, fund, build and operate new nuclear plants, but the planning process for building nuclear plants is expected to have been streamlined after changes made to planning laws outlined on Monday.

Industry secretary Alistair Darling has said it will be more than likely that any new plants will be built on or near existing nuclear facilities. There will now be a consultation process which will run until October 10 before any further decisions are made.