Castle & Cooke Inc. yesterday said it may build a $750 million wind farm on Lana'i that could provide 15 percent to 20 percent of O'ahu's power needs.

The company, which owns 98 percent of Lana'i, is conducting wind and other feasibility studies in preparation for a decision on whether to build what would be the state's largest wind farm, said Castle & Cooke President Harry Saunders.

"Our intention is to go forward," Saunders said yesterday. "We're hoping to have a 'go' or 'no go' decision by the end of the year."

The proposed wind farm would generate 300 to 400 megawatts of power, or 10 times more energy than Hawai'i's largest existing wind farm. To put that in context, the total electric generating capacity for the Big Island is 300 megawatts.

The Lana'i wind farm power could be sent by undersea cable to O'ahu. However, it would not relieve O'ahu's need for a new, proposed biofuel power plant at Campbell Industrial Park, according to Hawaiian Electric Co.

HECO spokeswoman Lynne Unemori said wind farms provide intermittent power and wouldn't address O'ahu's need for a more reliable power source.

"We certainly welcome getting additional renewable energy," she said. But "it wouldn't remove the need for a new generator."

Despite consistent trade winds, Hawai'i gets little of its electric power from the wind. Because Castle & Cooke owns most of Lana'i, it may be able to avoid the type of public opposition that has tripped up wind farm plans in the past.

Community and cultural concerns effectively killed Hawaiian Electric Co.'s $70 million proposal to build a wind farm above the Kahe power plant in 2005. The plan to place 24 to 26 wind mills on a ridge drew opposition from Wai'anae Coast residents who considered the turbines unsightly and believed they would desecrate a sacred Hawaiian place.

LITTLE POWER SO FAR

The five existing or planned wind farms in the state, not counting the proposed Lana'i farm, only satisfy about 1 percent of the state's electricity demands, according to the Department of Business, Economic Development and Tourism.

A new $69 million Kaheawa Wind Power project on Maui, for example, uses 20 of General Electric's 1.5-megawatt wind turbines, which produce 30 megawatts of energy. The Kaheawa wind farm, on state land above Ukumehame, produces about 9 percent of Maui Electric Co. needs and eliminates the need for an estimated 244,000 barrels of imported oil annually.

SOLAR FARM PLANNED

Also yesterday, Castle & Cooke said it plans to build the largest solar photovoltaic farm in the state on Lana'i.

The solar farm would meet up to 30 percent of Lana'i's electricity demand.

The 1.5-megawatt solar farm will be built by a Castle & Cooke subsidiary, Lana'i Sustainability Research LLC, on a 10-acre site in south Lana'i. The $13 million to $18 million project could be completed by year's end.

"The time to move forward with renewable energy is now," said David Murdock, chairman and owner of Castle & Cooke Inc., in a news release about the solar plant. "Castle & Cooke is uniquely positioned on Lana'i to move forward to quickly meet — and exceed — the state's mandate of 20 percent sustainability by 2020."

The proposed site of the solar farm is in the Palawai Basin, about two miles south of the Maui Electric Co. power plant.

This project will add 14.4 percent to the installed electric generating capacity on Lana'i, and its daytime duty is expected to provide up to 30 percent of the island's power demand, said Maui Mayor Charmaine Tavares.

"This clean, renewable energy project will replace the equivalent of 202,400 gallons of diesel fuel, thereby avoiding 4.5 million pounds of global-warming carbon dioxide emission in Maui County annually," Tavares said in a news release.

SOLAR ADVANTAGES

Castle & Cooke is in the process of negotiating a power-purchase agreement with MECO to provide the solar power to Lana'i's community through MECO's electrical grid. Castle & Cooke said the solar farm could help mitigate future rate increases.

While solar power generation is small in Hawai'i compared to other renewable-energy sources such as geothermal, it offers advantages, said Maria Tome, an alternative-energy engineer at the state DBEDT.

Solar has the ability to be located on a building rooftop or other location where power is needed, Tome said. The technology makes more sense on the Neighbor Islands where utility rates are highest.

Castle & Cooke's solar project may qualify for a state technology investment incentives and a commercial solar, or photovoltaic, power tax credit program that rebates 35 percent of actual costs or $500,000, whichever is less. The company also might tap a 30 percent federal photovoltaic investment tax credit, Castle & Cooke said.

Another alternative-energy project that Castle & Cooke is pursuing on Lana'i is growing feedstock for biofuels.

"With the support of the state and the counties, this agreement to build Hawai'i's largest solar farm is just the first step of our plans for renewable, sustainable energy," Murdock said.

Reach Sean Hao at shao@honoluluadvertiser.com.