INSIDE our freezer it’s a chilly -20C, but behind it, its quite warm. The freezer takes heat out of the food and pumps it out as heat.
This is all done with a clever system of compressing and expanding gasses. The same reason why aerosol cans get cold, and bike pumps get warm.
You can heat a home like this too, using a heat pump system. It’s the same technology as a freezer – but the other way round. It takes heat from outside and puts it inside.
It works best with underfloor heating because it doesn’t have to pump the heat to as high a temperature as needed with radiators. However, with well-insulated house and efficient radiators, a heat pump will work ok.
Heat pumps can pump heat from the ground (ground source heat pump), from nearby water (water source heat pump), or from the air (air source heat pump or ASHP).
Air is the hardest source to pump heat from – but ASHP are the easiest to install. They look like air conditioning units. You’ll be seeing a lot more of them and as they become more common, their prices will come down.
Pumping heat from somewhere else uses less energy than making heat. A heat pump using 1kWh of electricity is equivalent to over 3kWh of conventional heating. This makes heating your home with electricity competitive with gas.
So why are we going through the upheaval of a new heating system with replacement radiators? We’re cutting our use of fossil fuels and trying to power our home entirely on renewable electricity.
Global warming can’t be stopped until we stop burning fossil fuels. Where boilers can’t be replaced, fossil fuel gas will be replaced with bio-gas, or hydrogen created with renewable electricity.
Gas is being phased out by the government as part of their wider move to tackle climate change. By 2025 gas heating will be banned from any new housing built. So your boiler will become extinct.
Our new air source heat pump won’t be very expensive to run but it is quite an expensive purchase. However, there is help available. We were successful in applying for a Green Homes Grant which covers much of the cost up-front fitted by a local provider.
If we hadn’t been successful, we could still receive the Renewable Heat Incentive – a payment over a period of seven years which should roughly cover the cost of the system.
In 8-10 weeks, we’ll have a something like a small air conditioning unit at the side of our house, and we’ll bid farewell to that caged pipe outside puffing hot CO2 into the atmosphere.
And we’ll gain some extra cupboard space where the boiler once lived. Best of all it’s a small step towards helping reduce climate change.
Turn Lyme Green