The proposed Auwahi Wind Energy project could begin construction in 2011 and commence commercial operations in 2012 on the Ulapalakua Ranch in the remote southeastern region of Maui.

Terms of the agreement were not disclosed.

"Consistent with our growing renewable presence in the southwestern United States, this project further expands Sempra Generation's footprint in one of the fastest growing renewable energy markets while further advancing the sustainability goals of Maui and the state of Hawaii," said Michael W. Allman, president and chief executive officer of Sempra Generation.

An important component of the Maui wind-power project is the development of a battery energy storage unit. The battery could store as much as 28 megawatt-hours (MWh) of wind energy generated by the project's windmills during the typically windy morning and night hours. The battery power could be stored until late afternoon, when electricity consumption typically reaches its peak, or could be utilized to regulate and smooth intermittent wind power, providing a valuable source of grid stability for Maui Electric.

Sempra Generation recently submitted a proposal to the U.S. Department of Energy to co-fund costs associated with an expansion of the battery energy storage facility to 72 MWh.

The integrated wind and battery energy storage project could serve as a prototype to help maximize the energy output of other wind power projects in Hawaii and throughout the world.

"Shell WindEnergy Inc. has re-assessed its wind development efforts in Hawaii and will concentrate on projects on the U.S. Mainland and Canada that are more aligned with our strategic direction," said Dick Williams, president of Shell WindEnergy Inc. "Our portfolio consists of eight wind farms on the U.S. Mainland with a total capacity of almost 900 megawatts. Going forward, we will continue to support Shell's overall strategy of diversifying its energy mix by developing energy sources that have low carbon emissions."

The project would help Maui attain its goal of achieving 95 percent of its electricity from renewable sources by 2020.

In 2008, the state of Hawaii and the U.S. Department of Energy set goals associated with the state's Clean Energy Initiative.