The government thinks building more nuclear power stations will help tackle climate change and secure energy supplies.  Energy efficiency is at the heart of the government’s energy white paper, unveiled by ministers this lunchtime. Trade and industry secretary Alistair Darling told the House of Commons that it would not be easy to implement the proposals, which seeks to tackle environmental and energy security issues by focussing on energy efficiency. Among the goals set by the white paper are tripling the amount of electricity from renewable sources by 2015 and cutting emissions by up to 33 million tonnes of carbon by 2020. It hopes to achieve these aims by introducing new real-time ’smart meters’ from 2008, publishing a biomass strategy, legalising the storage of natural gas underneath the North Sea and funding for the development of low carbon vehicles. “Every action set in train by this white paper is important, and none will be easy. Nor can we become a low carbon economy in a single step,” Mr Darling told the Commons. “But if each of us acts we can start to deliver the low-carbon economy vital to our prosperity,” he said. The government stopped short of a full endorsement of nuclear power in a bid to avert the expected fierce debate between policymakers and environmentalists. Instead ministers framed nuclear power stations as an environmentally-friendly energy source but avoided making concrete decisions on the issue, launching a new consultation. Conservative shadow trade and industry secretary Alan Duncan contrasted Tony Blair and Gordon Brown’s strong commitment to nuclear power with the white paper’s less clear preference, saying the difference reflected the “confusion” at its heart. “The government says that certain things must be done, but its policy, at best, says that they might be done,” he said. “It offers nothing definite on nuclear or anything else, it heralds the collapse of carbon capture, it continues an irrational regime for carbon penalties and incentives, it provides little or no prospect of hitting renewables targets, it does not offer the security we need. “Ten months after the energy review it is still content free, not carbon free,” he concluded