San Francisco's landmarksolarincentive program has led to a near quadrupling of applications for new solar installations in the city during its first three months, Mayor Gavin Newsom said Wednesday.

But while residential customers are signing up in record numbers, only six businesses have applied for the program's more generous commercial incentives so far, putting impetus behind a program launched Tuesday by the city to entice more of them to go solar, Newsom said.

"The big question is what the business community does," Newsom said after a press event on a Sunset district rooftop featuring solar panels installed under the city's incentive program.

Since the "GoSolarSF" program launched in July, the number of applications for solar installations to the state's California Solar Initiative within city limits has jumped to about 60 per month, the mayor's office reported – a 275 percent increase compared to an average of 16 per month in the same period last year.

Newsom said those increases show the popularity of the program, which offers incentives of $3,000 to $6,000 for residential solar installations and up to $10,000 for commercial installations (see San Francisco Solar Incentive Becomes Official, San Francisco Offers Solar Subsidies, San Francisco Solar Subsidy Steps Closer and Solar Setback in San Francisco).

Newsom said he would push to increase funding for the 10-year program, which is now set at between $2 million to $5 million per year.

The city set aside $3 million for the program this fiscal year. Of that, about $900,000 has been pledged to applications under the program, leaving $2.1 million for applications yet to come, said Ed Harrington, general manager of the San Francisco Public Utilities Commission.

Of the roughly 195,000 rooftops in the city, 871 now have solar panels installed, up from 583 in February 2007, said Phil Ting, Assessor Recorder of the City and County of San Francisco.

But while residential applications have zoomed, only six businesses and three nonprofit organizations so far have applied, despite the more generous $10,000 incentive available to them, Harrington said.

Newsom, who mentioned the lag Tuesday, said he sensed the reason is that "a lot of businesses are not aware of the opportunity."

On Tuesday, he also suggested that the economic downturn and financial crisis might be discouraging businesses from investing in new solar installations.

The situation led his office to announce an outreach effort that will offer up to 1,600 businesses free energy-efficiency audits and solar-installation estimates in hopes of doubling the city's solar power generation from 5 megawatts to 10 megawatts by next year (see SF Mayor Says Solar Program Lags Expectations).

On Wednesday, Newsom also highlighted the program's "green collar job" program, which links the more generous $6,000 residential incentives to installations that include companies that employ workers from approved workforce programs.

So far, eight workers have been hired through the job program, which includes five installation companies now certified to participate and 11 more seeking certification, he said.

While he acknowledged that number was small, he said he expects it to grow as the incentive program gains popularity.