Britain is facing a huge electricity supply gap because of the closure of coal and nuclear plants, with plans to plug the shortfall "unrealistic", the Government has been warned.
According to the Institution of Mechanical Engineers, the gap could be as much as 55% by 2025, with proposals to build combined cycle gas turbine (CCGT) plants insufficient to deal with the problem.
A report by the institution detailed the impact of closing all coal-fired power stations by 2025, ageing nuclear stations stopping generating power, and growing demand for power. It said the UK does not have the resources or the skilled workers to build the number of power stations needed.
Report author Dr Jenifer Baxter said the UK's growing population and increased electricity use meant it was facing a "supply crisis".
"The UK is on course to produce even less electricity than it does at the moment," said Dr Baxter.
"We cannot rely on CCGTs alone to plug this gap, as we have neither the time, resources nor enough people with the right skills to build sufficient power plants."
Dr Baxter warned electricity will become less secure and affordable as imports leave the UK's supply at the mercy of the markets, weather and politics of other countries, with companies lacking incentives to invest in electricity infrastructure or innovation.
"Under current policy, it is almost impossible for UK electricity demand to be met by 2025," Dr Baxter said.
The GMB union said the Government needed to set out a long-term plan rather than "kicking this can down the road".
A Department of Energy and Climate Change spokesman said: "New gas power stations are being built and we are investing in cleaner energy, such as nuclear and shale gas, to ensure hardworking families and businesses have secure, affordable energy supplies they can rely on now and in the future."