The chief of SSE has warned that the government’s new windfall tax on electricity generators could threaten the UK’s energy security.

This concern was shared by the leading trade association Energy Uk earlier this year.

Earlier this month, the government announced the introduction of the Electricity Generator Levy – it said the increase in the wholesale price of gas resulted in “extraordinary profits” made by some electricity generators.

In an interview with the Sunday Telegraph, SSE Chief Executive Alistair Phillips-Davies said SSE may need to reduce the output of its hydroelectric plants in January and February to avoid the tax.

Mr Phillips-Davies warned: “That will mean there’s less certainty of supply over the absolute peak.”

The energy giant plans to invest £12.5 billion in the UK’s energy system by 2026. The boss of SSE said: “The £12.5 billion out to March 2026 is a fully funded plan, even with the windfall tax.

“And we still feel very confident that we can make that £24 billion investment. Maybe our ability to expand that £24 billion isn’t as high as it would have been. But we are still there, we are still ready.”