The city has broken ground on the next phase of its $302 million waste-to-energy project at Campbell Industrial Park.

The project, once completed by late 2011 or early 2012, will be the third boiler at the HPOWER facility, burning 900 tons a day and producing 25 to 30 megawatts of electricity or enough to power 25,000 homes, the city said.

The construction will create 300 jobs and produce 34 new full-time employees upon completion, the city said.

“;By greatly improving our island's sustainability, this project will be a tremendous help to us all,”; said Mayor Mufi Hannemann during the ceremony yesterday.

HPOWER now utilizes two fuel boilers capable of processing a combined 2,160 tons per day of non-hazardous municipal solid waste, producing 57 megawatts of power, enough for 45,000 homes, the city said. With the third boiler, HPOWER will supply 6 percent of Oahu's electricity, up from the current 4.5 percent.

The facility reduces the volume of waste by 90 percent, burning it at 1,800 degrees Fahrenheit and turning it into inert ash.

HPOWER has been in operation since May 1990 and has burned more than 12 million tons of waste and offset 12 million barrels of imported oil that would have been burned to generate electricity, the city said.

HPOWER, formally the Honolulu Program of Waste Energy Recovery, burns about 60 percent of the 1.8 million tons of garbage on Oahu annually.