Sempra Energy said Thursday that it has signed a 20-year contract to sell Maui Electric Co. 21 megawatts of wind energy from a wind farm to be completed by the end of next year.

Semrpa said the power will be generated at its Sempra's Auwahi Wind project, and the contract will be administered by its subsidiary Sempra Generation.

Financial terms of the deal were not disclosed.

The wind farm will be located on the Ulupalakua Ranch in southeastern Maui.

Construction is set to begin by early 2012 and should be done by the end of the year. The wind farm will help Hawaii reach its clean energy goal of 40 percent of electricity from renewable sources by 2030. It is to create about 150 jobs and serve the equivalent of 10,000 homes.

Shares of Sempra Energy fell 60 cents, or 1 percent, to $53.50 in afternoon trading.