Sempra Generation, a subsidiary of Sempra Energy, has signed a 20-year contract to sell 21MW of wind energy to Maui Electric Company from the Auwahi Wind project on the Ulupalakua Ranch in Maui, Hawaii.

The construction on Auwahi Wind project, which is expected to begin in early 2012, is currently undergoing an environmental review by Maui County, and state and federal agencies.

The company said that Auwahi Wind will be capable of generating clean electricity equivalent to the amount used by 10,000 typical Maui homes when fully operational.

This new source of locally-produced wind energy will help Hawaii reach its clean energy goal of 40% of electricity from renewable sources by 2030.

The battery storage unit could store as much as 12MWh of wind energy generated by the project’s wind turbines during the typically windy times.

The contract between Maui Electric Company and Sempra Generation is subject to approval by the Hawaii Public Utilities Commission.