Air source heat pumps, which can warm buildings using a fraction of the energy of conventional gas boilers, are subject to complex building regulations in Scotland – but not in England and Wales.

Figures from energy regulator Ofgem show only 26 per cent of domestic renewable heat installations in Scotland are air source heat pumps, compared to a UK average of 39 per cent.

Scottish Renewables, which represents more than 300 organisations working in renewable energy, is working with government to have the planning rules – known as permitted development rights – changed.

Stephanie Clark, policy manager at Scottish Renewables, said: “Heat pumps are a fantastic tool with which to combat fuel poverty. Scotland has ambitious renewable heat targets and this is technology which can help us reach them.

“In England and Wales, homeowners can install an air source heat pump without the need to apply for planning permission. In most cases in Scotland, they must do so.

“This adds a significant hurdle in terms of time and expense, and is putting many people off.”

An air source heat pump extracts heat from the outside air in the same way that a fridge extracts heat from its inside. The technology can extract heat from the air even when the temperature is as low as -15C.

This heat can then be used in radiators or underfloor heating systems, as well as to provide hot water in a building.

Heat pumps need a small amount of electricity to run, but the energy they extract from the ground, air, or water is constantly being renewed naturally. The technology was first described by William Thomson, the first Lord Kelvin, at Glasgow University in 1852.