Hawaiian Electric Co. hopes to run a new Campbell Industrial Park power plant on renewable biofuels — ethanol or biodiesel — but some energy advocates say those fuels will come from plantations burned and bulldozed out of native forests, and that the utility should follow other avenues.

The utility, on the other hand, says the community desperately needs the extra generating capacity now, and that many of the alternatives are still unproven technologies.

HECO proposes to build a 110-megawatt single-cycle combustion turbine generator at Campbell Industrial Park. The unit would be operational by the middle of 2009. It is designed to be able to start up quickly to meet load demands, and to be fuel-flexible. It would not only be able to burn ethanol and biodiesel, but also fossil fuels such as diesel and naphtha.

The arguments about the need for and alternatives to the plant have been played out before the state Public Utilities Commission, and HECO is waiting for the commission's approval of the plant as well as an air pollution permit from the state Department of Health.

HECO spokesman Peter Rosegg said the utility is committed to using biofuels to run the plant.

"The Campbell Industrial Park unit will be the first commercial plant to run 'green,' entirely on renewable biofuel," he said. HECO senior vice president for operations Tom Joaquin said that to the utility's knowledge, "there is not another utility combustion turbine electricity generator using or planning to use biofuels in the United States, and probably the world."

The citizens group Life of the Land has opposed HECO's plan, arguing that biofuels imported from abroad are often from plantations cut out of native jungle, and that other technologies using local resources should be emphasized for the future of Hawai'i's power grid.

"Right now Indonesia is third in the world in greenhouse gas emissions. They are mowing down rain forest and burning peat forests, releasing enormous amounts of carbon dioxide so that oil palms can be mono-cropped to produce biodiesel," said Henry Curtis, Life of the Land executive director.

Rosegg said biofuels have broad support from environmental groups across the nation, but he concedes that some worry about things like the loss of rain forests and competition between food crops and fuel crops.

"There are clearly some concerns, caveats and hurdles that need to be overcome," Rosegg said.

Curtis argues that there are three big resources that HECO should emphasize before building another combustion power plant.

One is aggressive conservation measures to reduce demand, as well as changes in power costs at different times of the day, to get people to shift power consumption to times when consumption is low. That can level out demand and minimize the peak loads that require the utility to have far more capacity than its average demand.

"Conservation is the thing you do first," Curtis said.

Rosegg said the utility supports a number of conservation programs and this month is presenting the Public Utilities Commission a proposal for a test of variable rate structures. It would provide customers with a lower rate for off-peak power use. That would tentatively be periods like 9 p.m. to 7 a.m. on weekdays and 7 a.m. to 5 p.m. on weekends and holidays. And there would be a premium for peak-time use, from 5 to 9 p.m. weekdays.

Seawater air conditioning, of which the first system for downtown Honolulu is under way, is capable of replacing a dramatic proportion of O'ahu's energy use, Curtis said. It would use cold deep-ocean water to chill O'ahu office buildings, rather than electricity from imported fuel. The system cools buildings for less cost than electricity-produced air conditioning, and Hawai'i is a world leader in developing the technology, he said.

Makapu'u's Makai Ocean Engineering has consulted with numerous international sites and has designed systems for Cornell University, the city of Toronto, a hotel in Bora Bora and others. The firm's vice president, Reb Bellinger, said there is considerable potential in the technology for Hawai'i, including at Waikiki and West Beach.

"We did a study for the state in the early '90s, and the best location on O'ahu is West Beach, where deep cold seawater is closest to shore," Bellinger said. Seawater air conditioning can stabilize the cost for air conditioning, which he said is "probably the largest single operating cost for offices."

Rosegg said that Hawaiian Electric supports seawater air conditioning and has committed that its downtown office structure will be one of the first buildings on the new Honolulu system, but he said the utility believes that the technology won't supplant enough power soon enough to avoid the need for new utility generation.

Curtis said a third major power source is one that was largely developed in the Hawaiian Islands — ocean thermal energy conversion, or OTEC. This involves generating power from the difference in temperature between the sun-warmed ocean surface and the chilly water from the deep ocean.

Curtis said a Hawai'i company, OCEES International, is prepared to install a system off Kahe Point if Hawaiian Electric will agree to purchase power from it. But Rosegg said his firm is being cautious with a technology that has not been fully implemented anywhere.

"We are monitoring installation of a small OTEC unit for the military at Diego Garcia in the Indian Ocean. To our knowledge no commercial ocean thermal energy conversion plant is operating anywhere in the world ... We believe it is not good use of ratepayers' or shareholders' money to chase a technology that could take unknown years to develop and get permits for," he said.

Curtis said that seawater air conditioning and OTEC are "real, 24/7 resources" produced from local resources.

"We're talking about a total switch to homegrown power. Ocean, wind and solar appear to be the way to go," but HECO seems to be dragging its feet, he said.

Reach Jan TenBruggencate at jant@honoluluadvertiser.com.