fraction from the high-temperature power plants is used for hot water production for district heating in co-generation plants. Thus, the energy efficiency is improved considerably. The low-temperature (<150˚C) fields are used mainly to supply hot water for district heating. The current utilisation of geothermal energy for heating and other direct uses is considered to be only a small fraction of what this resource can provide.
Geothermal utilisation at Reykjanes peninsula The Reykjanes peninsula in the southwest of Iceland is an active volcanic area. After nearly 800 years of inactivity, a
Figure 5. The total direct use of geothermal energy in 2020 is estimated to have been 9737 GWhth (35 052 TJ).
relatively small eruption was ongoing in Fagradalsfjall volcano at Reykjanes for a few months in 2021. Geothermal research has been ongoing in the area for decades with important contributions from ÍSOR and its predecessors in the form of geothermal exploration, drilling consultancy, well logging and testing, as well as resource assessment. Geothermal utilisation at Reykjanes on a large scale started by building a co-generation power plant at Svartsengi in 1976. The plant is located 50 km from Reykjavík and serves approximately 30 000 people with district heating. Due to the high salinity of the water (two-thirds that of sea water), it cannot be used directly for district heating as is commonly done in Iceland. Therefore, several heat exchangers are used to transfer the heat from the 240˚C brine to freshwater, which is distributed to the users at approximately 80˚C. The capacity of the plant for district heating is 190 MWth and for electricity 76.4 MWe. The energy company HS Orka also has another 100 MWe geothermal plant at Reykjanes that was commissioned in 2006 for electricity generation only. Expansion of that plant by 30 MWe is ongoing by adding a low-pressure turbine for better utilisation of the resource without extracting more fluid from the geothermal reservoir. A Resource Park has been built near HS Orka’s geothermal power plants at Reykjanes, based on the idea of maximum utilisation of the resource and minimum environmental impact of the activities. The Resource Park consists of spin-offs of different types where the Blue Lagoon, one of the most popular tourist attractions in Iceland, utilises effluent brine from Svartsengi power plant. Among other activities within the Resource Park are a fish farm and a fish drying factory utilising effluent heat from Reykjanes power plant, a methanol factory utilising both electricity and CO2 emission from Svartsengi power plant, and a company producing growth factors for medical research and skin care products by genetic engineering processes.
The role of the government
Figure 6. The low-temperature (<150˚C) fields are used mainly to supply hot water for district heating.
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ENERGY GLOBAL SUMMER 2022
It has been the policy of the government of Iceland to increase the utilisation of renewable energy resources even further for power generation, direct uses, and the transport sector. A broad consensus on conservation of valuable natural areas has been influenced by increased environmental awareness. Thus, there has been opposition against hydropower and some geothermal projects. However, a recent public opinion poll shows that the most preferred type of power plant is geothermal power plants. The ownership of energy resources in Iceland is based on the ownership of land. However, exploration and utilisation are subject to licensing. A master plan assessing the economic feasibility and the environmental impact of selected power development projects was adopted by the Icelandic Parliament approximately 25 years ago. It is a tool to reconcile the often-competing interests of nature conservation and energy utilisation on a national scale and at the earliest planning stages. The master plan is currently in its fourth phase, which is due to be completed soon. Direct involvement of the government in energy research has gradually decreased over the years. While the government still encourages and supports exploration for geothermal and
