The trust, the UK's largest heritage conservation charity, has renewed its ambition to hit net-zero by 2030.

Will Handford, the trust's renewable energy programme director, told Sky News it was "around halfway" on its own carbon reduction plan, and that the energy crisis made these targets "incredibly relevant".

"Things are obviously bringing energy right to the forefront of people's minds," Mr Handford said.

"But it's the same with us as with people's home: to get those costs down, and to try and save costs, the thing is to try and reduce using the energy first.

"It's the same principle in any property, whatever its size: check loft insulation, curtains, and double glazing."

The National Trust has worked on more than 130 renewable energy projects over the past nine years, reducing reliance on fossil fuels as well as establishing its own green energy supply.

Speke Hall, a 500-year-old Tudor mansion in Liverpool, has replaced its traditional heating system with the installation of a ground-source heat pump.

The pump, installed within a cellar of the property, means the house is no longer reliant on oil or gas and any remaining electricity demand is supplied by energy from a nearby wind farm.

Simon Osborne, the property's general manager, admits that he "needed convincing" that the 21st century technology would work in an historic building property, but says it's been "remarkable."

"We have a duty to care for these old buildings, and now we can better control its climate, as well as reducing our reliance on fossil fuels," Mr Osborne said.

"All this technology is scalable - it's a big system here because of the size of the property - but it's exactly the same system that would be in a residential home.

"And if it works in a 500-year house, it could pretty much work anywhere."

The UK government, which has a 2050 net-zero target, has recognised heat pumps will be a major technology to help reduce residential carbon footprints but acknowledges, for now, that units are currently too expensive.

In the short-term, it intends to make £1bn worth of funding available for home insulation projects as it seeks to reduce energy consumption by 15% by 2030.