Numerical Modelling of the Hveragerði High-Temperature Field

Abstract

The Hveragerði high-temperature geothermal field is located on the eastern margin of the Western Rift Zone and on the western end of the South Icelandic Seismic Zone. Located 40 km South-East of Reykjavík, Iceland and east of the Hengill Area, where the Hellisheidi and Nesjavellir geothermal power plants are located. The Hveragerði municipality district heating utility is one of the first district heating utility in Iceland, established in 1952. However, the geothermal field has been used for district heating since the early 1920s. Today the need for stable thermal power has increased due to the rapid population growth in and around the Hveragerði municipality. Reykjavík Energy and Veitur Utilities have high service standards set for district heating, in order to sustain that standard a better understanding on the Hveragerði geothermal field is needed. A better understanding can lead to a more economic and sustainable thermal power production. A numerical model was developed using TOUGH2. Available data was collected, and formation temperatures of wells were estimated using well temperature measurements. The formation temperatures were used to calibrate the numerical model. Little data is available on the production from the field; thus, the production was estimated using the population growth and the building types and sizes. The calculated formation temperatures and the estimated formation temperatures show a good match. The production simulation shows that the production results in little drawdown in the field. These results indicate that more could be produced from the field, without compromising sustainability.