Processing seawater through innovative underwater heat pumps provides efficient domestic heating, as well as cutting energy bills and carbon emissions, say Norwegian pioneers. Jim Drury reports.
You might be surprised to hear that the water from this Norwegian fjord is used to heat the homes and businesses of the city of Drammen. A steady 8 degrees Celcius, the water travels through underwater heat pumps. Here it's used to heat ammonia, a compound which boils at minus 33 degrees. It's this which makes the system different from other heat pumps, says Drammen District Heating chief Jon Ivar Bakk. SOUNDBITE (English) JON IVAR BAKK, GENERAL MANAGER OF DRAMMEN FJERNVARME, SAYING: "When ammonia turns to gas we are lifting the pressure in two steps, adding the energy into the ammonia. Then we condensate the ammonia and we release the energy into the district water... We can raise the temperature from around 60 degrees returning from the city up to 90 degrees and it goes in a loop all the time." Reaching such high temperatures means the system can be retrofitted to all gas-powered boilers. Distribution manager Anders Liang says there are other benefits. SOUNDBITE (English) ANDERS (PRON: ANDERSCH) LIANG, DRAMMEN FJERNVARME, DISTRIBUTION MANAGER, SAYING: "We use a large energy resource that is not exploited by others.....So we produce cheap energy that's for the whole city and it's environmentally friendly." Drammen used to be synonymous with smog. But far-sighted local authorities have cleaned up the city, which is home to more than 60,000 people. And the heat pump system, designed by Scottish firm Star Renewable and rolled out four years ago, is cutting 15,000 tonnes from Drammen's annual carbon emissions. Production manager Vidar Mathisen. SOUNDBITE (English) VIDAR MATHISEN (PRON: VEEDAR MATEEZAN), PRODUCTION MANAGER, DRAMMEN FJERNVARME, SAYING: "We pump in, we pump the same seawater out. There is not any pollution in this water." And the pumps need not be limited to Norway. SOUNDBITE (English) JON IVAR BAKK (PRON: YORN EEVA BUCK), GENERAL MANAGER OF DRAMMEN FJERNVARME, SAYING: "All over Europe you can use the same technology, definitely. As long as you have a water source, a stable temperature of above six degrees Celsius." With buildings responsible for almost a third of total global energy consumption, solutions like heat pumps could have a useful role in cutting global emissions.