Magma, based in Vancouver, will first buy an 8.62% stake for about $20mn, payable when the deal closes, and a 2.16% holding for about $5mn, due by 31 March 2010.

The company has an option to acquire an additional 5% share by infusing an additional $15mn into HS Orka. Closing of the agreement is expected in September.

HS Orka now has 175MW of installed geothermal power capacity from the from the Svartsengi and Reykjanes power plants.