A 90 MW geothermal power station, built in two phases, is the first step in the careful development of sustainable geothermal utilisation in the northeast.

Extensive preparation work was carried out at Þeistareykir this year. The unique nature of the area was considered during the execution of all preparation work and an emphasis was placed on working in harmony with the environment and in consensus with society.

A special emphasis has been placed on environmental issues during all preparation work for the Þeistareykir Geothermal Power Station. The main objective is to design a profitable and reliable power station that operates in harmony with its environment and nature. Preparation work is now underway in the area and construction is expected to begin in May, 2015

The Þeistareykir land area is a historic farm site which lies to the southeast of Húsavík.


In harmony with the environment

Nearly 3000 kilos of seeds have been sown in grazing areas and road sides in the Þeistareykir area.

The first 15 km of the access road from Húsavík to the site at Þeistareykir was completed and roadside edges were completed during the summer of 2014. Construction work on the road will be completed in the summer of 2015 including road surfacing for the entire length of the road, up to the station. More detailed information on the topic can be found in the chapter on Visual Impact.

Plans have been developed to re-vegetate any land lost as a result of the construction of the power station in cooperation with the municipalities of Þingeyjarsveit and Norðurþing and other local landowners. The Soil Conservation Service of Iceland is supervising the projects. In 2014, over 120 hectares of land was sown, including 40 hectares in the Þingeryjarsveit area, to reclaim grazing land. Over thirty seven thousand plants were planted in lupine covered land to the north of the Höskuldsvatn Lake.

Landsvirkjun has planted 37,118 plants, both birch and larch, in the lupine-rich area of the Höskuldsvatn Lake, in cooperation with local residents.

Reducing the visual impact of structures has been a key issue during preparation work since the Þeistareykir Power Project began. Massive amounts of material, extracted from the foundation of the power house, have been used to build earthen berms. These berms are located in front of the proposed power house and are used to reduce the visual impact of structures pertaining to the station. The same materials were ground down and used for road construction.

Visual aspects have also been considered during the design process for the power station and landscaping and finishing work is therefore completed alongside construction work. Examples of this include sowing on road verges and the utilisation of vegetation cover extracted from construction areas to vegetate the roadside and to cover earthen berms.  The project was successful and similar projects will be carried out during the construction period.

  • Umhverfisskyrsla_Myndir_1400x5008.jpg
    This picture shows the Þeistareykir road after landscaping and sowing in the road side area.
  • Umhverfisskyrsla_Myndir_1400x5009.jpg
    Over 37 thousand plants were planted to re-vegetate land in the lupine- rich areas to the north of the Höskuldar Lake.
  • Umhverfisskyrsla_Myndir_1400x50012.jpg
    Earthen berms were constructed to the south of the station site to reduce the visual impact of structures in the area.
  • Umhverfisskyrsla_Myndir_1400x50010.jpg
    Vegetation coverage was extracted from a large area at the powerhouse site.
  • Umhverfisskyrsla_Myndir_1400x50011.jpg
    Vegetation cover extracted from construction areas was used to re-vegetate the roadside area and to cover earthen berms to the south of the powerhouse site.
  • Umhverfisskyrsla_Myndir_1400x50013.jpg
    This picture shows the roadside area which was completed by using vegetation cover extracted from construction areas.

Environmental monitoring at Þeistareykir

Regular research and monitoring has been conducted within the Þeistareykir utilisation area since 2002. Researching the area during the preparation, construction and operational stage will give an overall picture of how and if the operation of geothermal power stations affect the geothermal resource and the environment.

The criteria for regular monitoring is outlined by the results of the environmental impact assessment in cooperation with the relevant permit issuers and is also based on Landsvirkjun’s experience in environmental monitoring.



Overview of monitoring

The objective of monitoring is to understand the baseline for environmental aspects before geothermal utilisation proceeds.

Vegetation areas
Air quality
GPS and gravity survey station
The shaded area on the map shows the industrial area in Þeistareykir

Extensive environmental research has been conducted on the geothermal resource and other environmental aspects in the Þeistareykir area. The objective is to understand the baseline for environmental aspects before geothermal utilisation proceeds. This enables us to understand if and how the operation of a geothermal power station affects its surroundings.

The geothermal resource

Extensive research has been conducted on the nature of the geothermal system and to assess the potential for geothermal utilisation in the Þeistareykir area.

A geothermal reservoir model has been developed by utilising all available data and is continuously updated as new information becomes available. Capacity testing began at the end of 2014 to simulate the proposed energy utilisation from the area. The data was then fed into the numerical model, which is a part of the geothermal reservoir model, and the information is used to assess the capacity of the resource before utilisation begins.

Seismic activity

A micro seismic monitoring network has been set up in the Þeistareykir area. The objective is to collect data for the area to assess the potential impact of operations on the environment before utilisation begins. Monitoring will provide information on how or if utilisation affects seismic activity. The data will also be used for ongoing research on the geothermal system.

GPS measurements

The GPS and InSAR measurements conducted in the area provide information on any changes to the land, both horizontal and vertical. The measurements can also be used to assess the effects of utilisation on the area.

Surface activity

The National Energy Authority has monitored geothermal activity at the surface in the Þeistareykir area since 1982. There have been significant natural changes to the surface temperature since monitoring began. Landsvirkjun monitors surface temperature in the area using photographic evidence and sampling. This detailed information on the development of surface temperature aids in the assessment of how and if geothermal utilisation is affecting the area.

Vegetation and birdlife

Landsvirkjun began monitoring vegetation and birdlife in the Þeistareykir area in the summer of 2012. Annual monitoring on the progress of vegetation, the nesting density of heathland birds and the occupation and breeding success of the falcon will be carried out.


The status of groundwater in the Þeistareykir area has been considered since organised research on the high temperature area began. The baseline for the water systems within the proposed affected area of the power station is therefore well known. Baseline knowledge on groundwater provides insight as to how and if Landsvirkjun’s operations affect the area.


Landsvirkjun has begun monitoring noise levels at Þeistareykir. A permanent noise monitor has been set up by the cabin in the area. Monitoring sites have also been determined where noise levels are measured six times a year. The objective of monitoring is to identify the impact of noise on the surrounding environment.

Air quality

Steam discharged from active wells and geothermal power station operations mostly contains water but also various gases (CO2, CH4 og H2S). A monitoring station was set up in the Kelduhverfi area in 2011 to monitor air quality in the vicinity of Þeistareykir area. A monitoring station was also set up in the Þeistareykir area this summer. The concentration of hydrogen sulphide in the atmosphere will be monitored on a monthly basis both in and around the Þeistareykir Geothermal Power Station. Samples will be taken from steam vents, wells and the production channel to monitor the chemical composition of gas and the percentage of steam. Natural gas emissions from the surrounding geothermal areas will be monitored and used as for comparison.


Further information

See Landsvirkjun’s website for more information on the development of the Þeistareykir power project and an overview of the research. Landsvirkjun’s Annual Report from 2014 also contains extensive information on the power project.