Hawaiian Electric Co. has signed agreements to buy electricity from two O'ahu renewable energy companies as part of an effort to meet lofty clean energy goals that it's agreed to with the state.

The utility has signed so-called purchase-power agreements with a 30- megawatt-capacity wind farm proposed for Kahuku and a 6-megawatt operation that wants to turn construction and demolition waste as well as other biomass into synthetic gas that will power generators.

"The fact that HECO is making a commitment and getting stuff going and entering into purchase power agreements is real movement," said Michael Hamnett, co-chairman of the Hawai'i Energy Policy Forum, a group that was formed to help pursue energy solutions for the state.

"It's no longer theory."

HECO is party to an agreement with the state that calls for it to obtain 40 percent of electrical power from renewable resources in the next 20 years. The mandate is part of an aggressive state objective aimed at making Hawai'i a clean energy showplace by 2030, with 70 percent of its power from clean sources.

Some 40 percent of this would come from renewable energy sources while 30 percent would come from efficiencies and conservation. Reaching the 40 percent level is easier on the Neighbor Islands because of richer wind and geothermal resources and lower power requirements.

On O'ahu, there are already some projects in place that move toward the goal, including the 46-megawatt garbage-to-energy HPower plant and a 110-megawatt plant that HECO plans to put into use this year. That plant will be powered by biodiesel made on the Mainland from animal waste fat and cooking oil.

The two new contracts must first be approved by the state Public Utilities Commission before the operations move forward with HECO. The first of the contracts is with Kahuku Wind Power, a firm backed by Boston-based First Wind, which was also the developer of the 30 megawatt Keheawa Wind project on Maui. First Wind also has pending a 21-megawatt project for Maui.

The second project is by Honua Power LLC, a local company that ultimately wants to build a $30-million to $40-million plant that will take organic materials, including construction and demolition debris, as well as nonrecyclable plastics and paper. The initial feed stock will be wood pallets that aren't shipped back to the Mainland, said Kevin Kondo, Honua spokesman.

These materials will be converted into gas that will be used in a conventional gas boiler system attached to generators. Kondo said Honua will start out with a 6 megawatt operation and will about double that in a second phase of the project.

All of the above projects, in addition to another 100 megawatts of projects being sought by HECO, add up to a little more than 20 percent of O'ahu's peak electrical needs of about 1,250 megawatts.

"These are all steps in the right direction, but there's a long way to go," said HECO spokesman Peter Rosegg. He said other efforts that could also help fill the gap include Ocean Thermal Energy Conversion in which exploits temperature differences offshore, and devices that capture wave energy.

There is also hope that a cable will be built that links 400 megawatts of proposed windfarms on Moloka'i and Lāna'i to O'ahu.

Hamnett said there may be other technology just "over the hill" that we can't see yet but may play a role here. He said that should help with Hawai'i's ambitious goal for weaning itself off of imported oil that accounts for about 90 percent of the state's energy needs.

"Personally, I think it's going to be tough to get to 70 percent indigenous energy by 2030, but I hope I'm wrong," he said. But "things are starting to happen."