One of our restored ponds, Pwll yr Ardd, heats up our Welsh Water Discovery Centre.

Sounds crazy doesn’t it?

But it’s not – it’s a bit like a fridge in reverse.

Under the water are lots of coiled pipes filled with liquid. When the water temperature is over 5°C, this liquid evaporates. Vapour turns back into liquid inside the building, releasing the heat from the water through radiators.

What pumps the liquid around?

Electricity. But heat pumps provide up to 4 times more energy than they consume.

Saves money?

Sure does. A heat pump can cut your heating bill by 30 to 40%.

Good for the environment?

Very. Heat pumps move heat around rather than generating new energy.

Could you use this at home?

Yes. Heat pumps can generate heat from still or running water and from the ground.