Nesjavellir Power Plant

ON Power operates not only the Hellisheiði Geothermal Power Plant, but also the Nesjavellir Geothermal Power Plant – our sister plant.

The Nesjavellir plant has an installed capacity of 120MWe and 350MWth, sending hot water to the capital region at a rate of around 1,640 l/s.

Nesjavellir is also located in the Hengill volcanic area therefore harnesses the same volcanic system that we do in Hellisheiði. It is located on the other side of the mountains, closer to Lake Þingvellir.

In the 1940’s, geothermal research was done in this area. It was believed that the area had a lot of potential for geothermal energy, but the drilling technology was not yet available in Iceland. In 1965, the City of Reykjavík purchased the area that now houses the Nesjavellir plant for future geothermal energy production. Construction on the plant began in 1987 and operations commenced in 1990.

Nesjavellir is now the largest supplier of geothermal water to Iceland’s capital region, alongside the Hellisheiði plant and low-temperature fields inside the city.

The plant is not open to the public, but ON Power maintains hiking trails around the plant that allow for fantastic views over the area. The plant also shares a valley with the ION Hotel and an Adventure Park.  

In addition to these two geothermal power plants, ON Power also operates a small hydroelectric plant called the Andakíslá Power Plant. This plant has been in operation since 1947, and has an installed capacity of 8MWe. You can read more about ON Power’s different plants here.