Seattle: Geothermal developer Magma Energy and wind and hydro company Plutonic Power have agreed to merge, creating a diversified renewables group with 366MW of operating assets in Canada, Iceland and the US. The merged company, to be known as Alterra Power, would be worth about $575m, the companies say..

The deal would give Plutonic shareholders 2.38 shares of Magma stock - based on its closing price the Friday before the deal was announced - for each Plutonic share.