Professor of geology Stefán Arnarson believes the geothermal areas around Hengill and Reykjanes are being overused. He told RÚV that geothermal heat is not renewable to any extent. Projects at the geothermal power plants in Hellisheiði and Reykjanes went ahead with too much speed, in his opinion.
Much debate has been going on lately regarding the rationality behind the size of operation of the geothermal plants. Gunnlaugur H. Jónsson physicist and former employee of the National Energy Authority of Iceland (Orkustofnun) told RÚV the geothermal areas are being overused. In order to maintain the level of productivity at the Hellisheiði power plant, one additional borehole must be drilled a year.
Gunnlaugur worries that if operation is not reduced, there won’t be enough geothermal heat in the future for heating up houses in the greater Reykjavík area or in Suðurnes on Reykjanes peninsula. The interests of generations to come are at stake, he says.
Stefán agrees with Gunnlaugur. “Steam from the boreholes, or the flow of steam from the boreholes, has decreased with time and continues to decrease. That has happened because the areas are overused; more is removed than flows in.”
According to Stefán, there is not enough steam available to operate the Heillisheiði and Reykjanes plants at full capacity. The reason, he explains, is that very large plants were built to begin with, although it is common knowledge that you must start small and gradually increase operation as you see how the area responds. He maintains that by starting this big in a new area, a huge risk has been taken. “And now it’s evident that it failed.”
According to RÚV, Bjarni Bjarnason CEO of Reykjavík Energy, has acknowledged that the Hellisheiði geothermal plant was built too fast and too large. Ásgeir Margeirsson, CEO of HS Orka, which operates the plants in Reykjanes and Svartsengi, does not believe that geothermal heat is being overused in those areas.