The government is determined to build a new generation of nuclear power stations, arguing that they are the best way of providing the country with secure, low emission power. Currently, Britain’s electricity generation comes from the host of sources, each with their own benefits and drawbacks.

Nuclear: A total of 20.5% of the UK’s electricity was generated by nuclear power in 2005 the last year for which figures are available  according to Department of Trade and Industry statistics. Nuclear plants have supplied power to the national grid since 1956, when the Calder Hall site in Cumbria first went into service. There are currently 19 reactors operating at 10 power stations around the country. Advocates of nuclear power Gordon Brown among them argue that it can play a major role in cutting carbon emissions and make the UK less reliant on imported energy. Some environmentalists, among them the veteran climate change expert James Lovelock, agree. However, critics insist the technology has much longer-term environmental problems and has always tended to end up being far more expensive than planned. A study commissioned by Greenpeace, released earlier this month, claimed that the average nuclear power station comes in four years behind schedule and runs three times over budget.

Gas: Natural gas is currently the most important single fuel for electricity generation, accounting for 38.5% of the UK total in 2005. The liberalisation of the UK gas market in the 1990s saw gas prices fall sharply, prompting electricity providers to switch from coal-fired power stations to gas-fired stations. This in turn led to a reduction in greenhouse gas emissions, because gas is less polluting than coal. However, the production of domestic North Sea gas is falling as reserves tail off, leaving Britain more reliant on imports with all the political uncertainty this can bring. The problem was starkly illustrated in late 2005, when a bitter dispute with Ukraine saw Russia reduce gas pipeline flows, affecting supplies to the EU.

Oil: Despite its unchallenged primacy as the fuel most consumers come into contact with directly, oil plays only a minor role in generation, providing just 1.4% of total output. It suffers similar drawbacks to those of gas environmental impact, falling domestic supplies and the insecurity of relying on imports.

Coal: Although coal-fired power stations still provide 34% of total electricity, the domestic coal industry is a shadow of its former self. While there were 180,000 people working in the coal industry before the 1984 miners strike, the current figure is just 5,600. The UK does still have economically viable coal reserves, but these are expected to run out with 10 to 15 years. Already, half the coal used in the country is imported. Coal-fired power stations are less polluting than they once were, but still produce large amounts of greenhouse gases. However, some believe the emerging technology of “carbon capture”, in which emissions are not released into the atmosphere, could see a new lease of life for coal.

Hydro: Power from running water currently supplies 1.25% of the country’s electricity, providing virtually emission-free power once the initial impact of building the plant has been taken into account. Unfortunately, hydroelectricity is most heavily dependent not on technology or political will but on a factor beyond the control of any government - geography. While Norway can produce virtually all its electricity through hydro stations, much of the UK’s potential in this area has already been used.

Wind: For all the many arguments for and against wind turbines, they are only a negligible player in total electricity production, making up just 0.75% of the national total. Wind is something the UK possesses in abundance, and the government is committed to building more wind farms to add to the 140 or so currently in operation. According to the DTI, wind energy will “make the main contribution” to the government’s eventual target of producing 10% of its energy via renewable sources. However, the issue divides even environmentalists, some of whom worry about the impact on the natural landscape of large-scale wind farms.

Other sources: Around 3.6% of electricity comes from other sources, two-thirds of this renewables such as biofuels, wave and solar power, and the remainder from the likes of burning landfill gas. Some have hailed biofuels as a potential environmental saviour, but others worry the scale of production needed to meet large-scale energy needs would cause more problems than it would solve.