Heat pumps idea can save millions in power bills

Renewable technology first envisaged by the physicist Lord Kelvin 150 years ago could use the country’s damp climate to save Scottish businesses £250 million annually.

The results of a study suggest heat pumps could be used to turn cold water from rivers, lochs and sewage plants into cheap, green energy for thousands of businesses.

The new report, commissioned by Glasgow University and due out in June, estimates that heat pumps could shrink the nation’s carbon footprint by the equivalent of 260,000 around-the-world car journeys every year.

“The only way to radically change the cost of heating is to harvest heat instead of burning new fuel,” said study leader David Pearson, director of Glasgow firm Star Renewable Energy, which carried out the research.

“Heat pumps aren’t new. They were examined by Scottish scientists 150 years ago. But recent technological breakthroughs can really help fight the battle against climate change.”

A heat pump collects warmth from cool water in rivers and lochs and delivers it at a higher temperature through compression. The process requires some imported energy, usually electricity, but returns the equivalent of three units of heat energy for each unit of electricity used.

The process – described in our graphic – means water as cold as 2C can be used to heat offices, homes and public buildings – water from the average Scottish river is 5C.

The study shows that heat pumps taking water from the River Kelvin could help Glasgow University slash £1.6 million a year off its £2m gas bill. The same technique could see Camlachie Burn used to cut heating costs by 80 per cent at the city’s Cranhill housing estate. Edinburgh airport could also spend 80 per cent less on power by dipping into the Almond, which flows alongside its runway.

“Heat pumps have the potential to save Scottish businesses £250m a year – enough to employ almost 10,000 people at the country’s average salary,” Mr Pearson said. “Scotland is a cool, wet country, and we have hundreds of rivers, streams and lochs which could provide the heat needed to warm office blocks, warehouses, supermarkets, cinemas and shops.”

He added: “Our biggest resource is falling from the sky.”

The report assesses the economic and environmental benefits of Scots businesses switching to renewable heating, but Mr Pearson said the technology has potential to help the 900,000 Scots homes in fuel poverty. The technology was first described by thermodynamics pioneer William Thomson, the first Lord Kelvin, at Glasgow University in 1852. The mathematical physicist is famed for defining the absolute temperature scale, named Kelvin in his honour.

.Stephanie Clark, policy manager at industry body Scottish Renewables, said: “With fossil fuel prices rising, and the price of renewables continuing to fall, it makes sense that heat pump technology should become more widespread in

Scotland.”