Hawaii’s booming solar energy market is proving to be a tonic for the state’s ailing construction sector. A mix of homegrown solar companies, construction firms, electrical contractors and entrants from the mainland are all boosting their payrolls as they push to meet the growing demand from homeowners and businesses for rooftop photovoltaic (PV) systems.

While the level of overall building permits has been fairly static over the past five years, permits issued for PV and solar hot water systems have soared. Solar projects accounted for 18 percent of all building permits issued on Oahu during the first five months of this year, up from 4 percent in 2007, according to data from the city Department of Planning and Permitting.

Hawaii is expected to be among the nation’s leaders in PV installations again this year after strong growth in the first quarter, according to a report released last week by the Solar Energy Industries Association. And construction jobs are on track to begin growing this year after four straight years of declines, according to a forecast from the University of Hawaii Economic Research Organization.

"The solar industry is providing so many of the new jobs," said Devin Ruiz, president of the Solar Training Institute, a San Diego-based company that offers a range of solar training courses in Hawaii. "A lot of people are starting companies and getting business licenses. It’s stimulating a lot of areas in the economy: construction, distribution, shipping and finance."

The firm has trained about 150 people over the past 18 months, including a group of 11 offenders incarcerated at Waiawa Correctional Facility, a minimum-security prison.

Out of 79 Hawaii companies in the photovoltaic and solar water heating businesses surveyed recently, 45 added workers last year, while four cut positions because of lack of work. The employers said they planned to hire anywhere from 171 to 197 workers on a net basis in 2012 across a range of job categories, according to the survey conducted by the state Department of Labor and Industrial Relations.

The largest number of new hires is projected to be installers, electricians and plumbers, the companies said. Although smaller in number, the biggest growth in hiring is expected to be for sales representatives. Employers said they planned to hire a "somewhat smaller" number of management, engineering and administrative support staff.

Bonterra Solar has increased its spending on manpower in Hawaii sixfold since expanding from California four years ago, said Andrew Yani, company principal and founder. Bonterra has about 10 full-time employees in Hawaii, and works with partners that employ from 45 to 50 workers at any given time on Bonterra PV and solar hot water projects, Yani said. That arrangement gives Bonterra flexibility with its labor costs so it doesn’t have to lay off anyone if business slows, he added.

Solar City has boosted its workforce to 66 employees since launching its Hawaii operations about a year ago, said Jon Yoshimura, director of government affairs.

"We’ve had steady growth. For years people have been talking about the ‘brain drain’ and kids having to leave Hawaii for the mainland to get a good job. At Solar City, there are a group of us who have been able to come back to Hawaii because of the solar industry," said Yoshimura, who previously worked as communications director for Sen. Daniel Akaka in Washington, D.C.

The state Workforce Development Council is spearheading Hawaii’s effort to train workers for the solar industry using a $6 million federal State Energy Sector Partnership Grant. The Council, which is under the state Labor Department, is working with county governments, the community colleges, Goodwill Industries, the state Department of Public Safety and the General Contractors Association to develop a qualified workforce.

Hawaii’s high electricity prices have made PV systems an attractive alternative to utility-produced power. But part of the recent growth has been spurred by government incentives, which critics say have outlived their usefulness.

A 35 percent state renewable-energy credit cost the state $30 million in lost revenue in fiscal year 2009. And that could potentially grow to $70 million by fiscal 2013, according to a recent estimate the Department of Taxation produced for the state Council on Revenues.

In addition, the city and county of Honolulu has lost millions of dollars from waiving fees for the installation of PV systems. The exemption cost the city $3.6 million in lost fees last year, according to the Department of Planning and Permitting.