Variations in demand are a “fundamental problem” when replacing one fuel with another.

Converting all heating from gas to electricity would require a massive increase in generation capacity, shadow energy minister Alan Whitehead has warned.

Speaking at a Labour party fringe meeting, sponsored by gas company ESB, Whitehead said that the variation in demand for heating vis-a vis that currently existing for electricity was the “fundamental problem” facing any attempt to replace one fuel with the other.

He said: “The variance is six times as big during the day. Since most of our homes are heated by gas we simply wouldn’t be able to produce enough capacity to make that happen.”

“We need to proceed with decarbonisation of heat by keeping gas in the system but not as we know it. Rather than ripping all the boilers off the wall, we want to start replacing the gas going in the heating system.”

He said that the solution was to “progressively decarbonise the gas grid by physically injecting other forms of green gas, such as biomethane”.

Whitehead also warned that electricity generation cannot be expected to continue to shoulder the burden of decarbonising the energy system, and that efforts on heating were lagging.

“The danger is that electricity will bear all the burden and we will not reach the target by that route alone. We need to take heat seriously.”

But he said that by undertaking measures, principally by installing better insulation, it would be possible to reduce the demand for gas by 20 per cent.

“We can get ourselves a long way down the route by simply not using the stuff in the first place.”

He said a decision to roll out hydrogen into the gas network would have to be made on a national basis.

Polly Billington, director of the UK100 network of councils, agreed that decarbonising needed to be carried out urgently and at a large scale. She said: “We can’t faff around. This is not the time to do this stuff in labs like Professor Brainstorm.”