Heating Husavik
Husavik – a small urban community on the north coast of Iceland, 40 km from the Arctic Circle – is a model of how energy efficiency can be integrated to a unified whole.
Keeping warm. Geothermal water is used for both space heating and electricity (Photo: Mc Lunaar)
Húsavík is known primarily for whales, fossils and salmons. For persons with technical interest, the town is also known for its new CHP plant based on utilisation of geothermal energy. Located some 20 km south of Húsavík is the Hveravellir geothermal area. From there Húsavík receives geothermal water for the district heating system. Utilisation of geothermal energy in Húsavík started back in 1960 when the local swimming pool was connected to one of the hot water springs in the area. Húsavík started utilising the geothermal hot water from Hveravellir as early as 1970.
Spreading the heat
The design of a new integrated energy system started in 1998 and finished in 2000. The concept is as follows: The high temperature level of the geothermal water at Hveravellir was used for electricity production, space heating and various industrial applications. The benefits of such a multi-use of the energy were many; electricity production would be economical for Húsavík since the town would no longer need to purchase electricity in addition to creating new jobs and increasing the scope of new jobs.
Electricity production combined with utilisation of hot water of various temperatures for space heating, industry and fish farms increased the value of the energy, since the total energy efficiency increased.
Fish farms and pharmaceutics
According to the concept, once the geothermal water arrived in Húsavík, it would first be utilised for applications requiring temperatures higher than 115°C - electricity production in the CHP plant and various industries. Once the temperature had fallen to 80°C through these processes, it would be utilised in the district heating distribution system as previously - for space heating, industrial purposes and snow melting.
Among the district heating consumers are several industries:
- A fishing farm presently uses about 4-6 l/s of 80°C water in addition to 20 l/s of the 24°C cooling water from the condenser at the CHP plant. The annual fish production at the moment is 1.5 million salmon smolt (2 years old salmon) and 140 tons of trout. The trout production is expected to increase to 200 tons next year.
- A factory for producing timber-flooring boards uses 80°C hot water to dry the wood in specialised drying compartments.
- A factory producing dried fish. Actually the annual production is 2,500 tons and the production is exported to Nigeria. The drying process takes place in specialised drying compartments, using 80°C hot water to heat air before blowing it through the compartments.
- A factory producing glucosamine. Glucosamine is a compound used in the pharmaceutical industry for arthritis drugs and other purposes. The production requires water in the temperature interval between 80°C and 120°C.
Success story
The geothermal energy project in Húsavík is an excellent example of how energy efficiency – even in Iceland where enormous resources of relative cheap energy are available – is now part of the considerations when new energy projects are to be realised.
