Jarðvarmi

Kröfluvirkjun

Mývatn

The Krafla power station is a geothermal power plant with high and low pressure steam from 18 boreholes driving 2x30 MW turbines. During the completion of Krafla in 1997-2002, Verkís provided consulting services for all electrical- control- and protection equipment, as well as for civil work for the steam supply system. Verkís also conducted all testing and start-up commissioning for the electrical, control and protection equipment.

 Stærðir:  60 MW og 400 GWh/ári
 Verktími: 1997 - 2002

Almennt um verkefnið:
The Krafla Power Station is now operated by the National Power Company of Iceland Landsvirkjun. The development of the Krafla geothermal power plant began in 1974 but it was not until 1978 that the first 30 MWe turbine was connected to the network. The second phase of the plant was implemented in 1997 with the installation of a second 30 MWe turbine and the renewal of the existing electrical, control and protection equipment. In the following years other systems were also refurbished, namely the steam supply and 132 kV substation. The refurbishment was completed in 2002 and the plant generation capacity is now about 500 GWh p.a.

Krafla geothermal field is located in a well known geothermal area, in northern Iceland and Verkís has been involved in the development of Krafla since the very beginning. The history of Krafla has been turbulent, starting from the onset when volcanic activity jeopardized the plant's existence just prior to its connection to the network. The volcanic eruptions which ensued during the period between 1975 and 1984 caused corrosive vapor to enter the geothermal system which in turn altered the chemical properties of the steam supply, increased its corrosiveness and destroying the supply lines. Despite these difficulties the first turbine was connected to the network in 1978.

As a result of the volcanic activities, the second turbine was not erected during the first phase as originally planned and the power plant was commissioned with only one of the two purchased units operating and at only approximately 10% capacity. In the following years, the amount of harnessed steam was gradually increased until the unit was operating at 100% capacity in the early 1990s. In 1996, drilling prospects showed good results and the second phase of the plant was implemented. The second 30 MWe turbine was installed in 1997 increasing the plant capacity to the 60 MWe originally planned. At full capacity the power plant utilizes 110 kg/sec of 7.7 bar saturated high pressure steam and 36 kg/sec of 2.2 bar saturated low-pressure steam.

Verkís has been involved in the initial plant development and later on in its refurbishment and completion. During the refurbishment stage, Verkís was in charge of the design and construction supervision of the steam gathering system i.e. sites for drilling rigs, access roads, steam collecting mains, steam separator station etc. in addition to overseeing the conceptual design and detail design, site supervision, testing and start-up commissioning of all electrical- , control- and protection systems.

More on Landsvirkjun website.