Hawaiian Electric Co. announced a plan Tuesday to buy wind energy from both Lanai and Molokai.

As part of the proposed arrangement, Castle & Cooke will scale back its Lanai wind farm from 400 megawatts to 200.

The overall deal could be considered in its infancy, considering all the steps that must fall into place, including environmental impact studies and land acquisition on Molokai. First Wind, co-owner of the Kaheawa Wind Farm on Maui, will attempt to build 200 megawatts of wind generation on Molokai, although it has no land there yet.

The arrangement is being called "Big Wind," and it will support HECO's commitment to the state to increase its renewable energy sources statewide to 1,100 megawatts by 2030. By comparison, Kaheawa is rated at 30 megawatts and is seeking approvals to expand to 51 megawatts.

Any agreements made would need the approval of the state Public Utilities Commission.

The proposal was announced jointly Tuesday by Gov. Linda Lingle, HECO, Castle & Cooke and First Wind.

"This agreement is a significant step forward for us," said Paul Gaynor, president of First Wind. "We now know HECO will purchase power generated by First Wind on Molokai.

"The proposed Ikaika Wind Power is a win-win for everyone - for us, for Molokai, for the state of Hawaii, and for our environment. We still have a long way to go and we look forward to continuing on our path forward together."

Both developers will cooperate with HECO to research and coordinate the reliable integration of the wind projects into the Oahu electric grid. As a variable power source, large amounts of wind-generated electricity added to a stand-alone grid pose challenges to maintaining a stable supply.

The projects also will depend on the ability to transmit the electric power to Oahu. The developers will assist the state in planning the undersea cable and in planning needed interconnection facilities by Hawaiian Electric.

First Wind has been promoting the development of a wind farm of 300 to 400 megawatts on Molokai since 2006, collecting wind data and doing environmental studies. It proposes to use Hawaiian homelands for the first 50 megawatts of towers and has been working with homesteaders to reach an access agreement.

A group of Molokai residents wants to buy Molokai Ranch outright, and First Wind committed $50 million toward a purchase fund. If the community group Ho'i I Ka Pono does purchase the ranch, First Wind would lease land for the rest of the wind farm from the community group.

However, in the past Molokai Properties Inc., which owns the ranch, lodge, golf course and 60,000 acres or one-third of the Friendly Isle, has said that is is not interested in selling its properties. The community group also has not come close to accumulating the $300 million that Molokai Properties Inc. has reportedly said its land and other holdings are worth.

There was no information available Tuesday evening about whether the company would consider leasing some of its land to First Wind.

Harry Saunders, president of Castle & Cooke Hawaii, said: "Lanai already is the site of the largest photovoltaic farm in the state, and this project will add significantly to the island's clean energy contributions for Hawaii. This agreement provides some certainty and assurances for us to continue to advance our wind farm proposal to harness Lanai's wind resources.

"This will result in the creation of green jobs and economic opportunities for Lanai, while protecting its environment and its special sense of place for residents and visitors," Saunders said.

Hawaiian Electric Executive Vice President Robbie Alm. said: "These two wind projects are absolutely essential to meeting our Hawaii Clean Energy commitments, and we are very pleased to be able to work with both developers to negotiate purchase power contracts as soon as possible."