The Big Island, for example, has a wind farm in Hawi with 16 windmills turned by the tropical breeze. The 100-foot turbines can generate enough electricity for more than 1,200 homes.

During one recent afternoon, however, the tradewinds were so weak that only eight of the turbines were turning, forcing the local electric utility to compensate with other energy sources to avoid power shortages.

"The potential is huge. We're not lacking the resources," said Maurice Kaya, chief technology officer for the Hawaii Department of Business, Economic Development and Tourism. "There may be technological solutions to this intermittence, but we're not there yet."

One potentially more reliable source of clean power is geothermal energy. Geothermal equipment draws heat from the molten rock deep within the Earth's crust to drive turbines. Hawaii, the home of Mount Kilauea, is a place of great volcanic activity.

The big advantage of geothermal energy is that it is an uninterrupted source of power.

"Unlike wind, geothermal is just like fossil fuel — we keep on producing," said Barry Mizumo, a consultant for Puna Geothermal Venture, which contributes 15 percent of the Big Island's peak power capacity.

Several businesses are also working on early efforts to take advantage of Hawaii's world-famous waves and harness the power of the tides. And Hawaii's electric utilities plan to convert plants to burn biofuels such as palm vegetable oil by 2009, Stahlkopf said.