Shoring up the UK’s “tenuous” supply of energy and decarbonising the power sector will cost an “eye-watering” £215 billion, according to Barclays.

The bank has calculated that £95bn alone will need to be spent on “disruptive” technologies, such as renewables, battery storage and distributed generation.

Barclays said: “Shoring up the UK’s current tenuous electricity security of supply in the face of this mass obsolescence of baseload generation capacity, combined with government policy to achieve a 57% reduction in greenhouse gas emissions by 2032, will require an eye-watering level of investment over coming years.

“With electricity security of supply already on a knife edge, the UK faces the obsolescence of approximately 40% of its current aged [gas-fired power station] fleet by around 2020 and approximately 70% of all reliable generation capacity by 2030.”

Loss of coal, gas and nuclear

Barclays said the UK would lose 15GW of coal capacity by 2025.

By 2030, the country would also lose 7.GW of its current 8.9GW nuclear capacity.

Some 13GW of gas capacity will be lost by 2020 and a further 9GW by 2030.

> Find out more about National Grid's future energy scenarios