| Title | Exploration and Utilization of the Námafjall High Temperature Area in N-Iceland |
|---|---|
| Authors | Ásgrímur Gudmundsson, Anette K Mortensen, Arnar Hjartarson, Ragna Karlsdóttir and Halldór Ármannsson |
| Year | 2010 |
| Conference | World Geothermal Congress |
| Keywords | Exploration, utilization, drilling, alteration, lithology, resistivity, conceptual model, reservoir modeling |
| Abstract | The longest successful cascading operation of geothermal utilization in Iceland is in the Námafjall high temperature area, often recognized as the Bjarnarflag field (Fig. 1). Initially in the early 1950s, the purpose of utilization was to mine sulfur from the geothermal steam, however the product did not turn out to be economic. After a short investigation period in the early sixties, drilling activities started in 1962. In the next eight years, nine steam-wells were drilled to fulfill the needs of a diatomite plant and a 3 MWe pilot power plant. The tenth and deepest well so far was drilled in the summer of 1975 down to 2000 m depth. Unfortunately an eruption event started in the Krafla central volcano at the end of the same year, which destroyed several wells in Bjarnarflag. This was followed by the successful drilling of two make up wells (BJ-11 and BJ-12) in the years 1979-80. In the early seventies, a central heating system for the Reykjahlíð village and nearby farms was constructed based on direct use, which turned out to be unfeasible because of a corrosive fluid. It was improved in 1984 by the installation of a heat exchanger. The utilization continued and in June 2004 the Mývatn Nature Baths opened. The warm geothermal waters of the Baths contain a unique blend of minerals, silicates and geothermal microorganisms, which are beneficial to the skin. According to new exploration program in NE- Iceland, three wells were directionally drilled in the years 2006-2008 to confirm the location of up-flow zones and improve the data input for the numerical model. Two of the wells appeared to be very powerful, 27 MWe in total, but the third one headed into colder environment. Further surface investigation of the Námafjall area and deep drilling exploration complemented the conceptual and natural state model of the area. Concurrently, a design for a 90 MWe geothermal power plant was worked out and assessment of environmental impact was completed. Landsvirkjun is the owner of the power plant in Bjarnarflag and got the privilege to exploit the area according to agreement with the state and landowners. |