The number of green jobs is growing throughout the Golden State, but it still represents just a tiny fraction of California's overall employment.

A study to be released today counted 159,000 green jobs throughout the state - everything from scientists devising new fuels and better solar panels to workers insulating buildings to cut energy use.

While the Bay Area has the most - 41,674 jobs, compared with 39,894 for the Los Angeles area - California's green economy is surprisingly widespread. It employs people in places as disparate as the San Joaquin Valley and the Inland Empire.

But taken together, those jobs represent less than 1 percent of employment in the state, according to the report's authors. Green industries have great promise for employment, but they haven't delivered yet.

"Green tech is not a panacea," said F. Noel Perry, founder of the Next 10 public policy group, which commissioned the report from consulting firm Collaborative Economics. "We believe green jobs are going to be a significant part of future jobs growth in California. But at the same time, we know they are a small proportion of the total jobs we have now."

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The report, "Many Shades of Green," aims to give an accurate account of the number and distribution of green jobs throughout the state.

California has embarked on an ambitious effort to fight global warming and encourage renewable energy, hoping to capture as much of the growing green-tech industry as possible. Supporters and opponents of that effort often issue competing estimates of how many jobs the state's climate change policies will create or destroy. In contrast, the Next 10 report tries to count jobs that are already there.

It does have a significant drawback. The survey, which collects and cross-checks data from many sources, is based on data from January 2008. It misses any jobs that might have been lost during last year's economic collapse or jobs that might have been created by this year's economic stimulus program from the federal government.

The study defines green jobs as those that develop new energy sources, save energy, conserve natural resources or reduce pollution, including greenhouse gases.

By that measure the number of green jobs in California has grown 35.9 percent since 1995, the earliest year for which Collaborative Economics could get consistent data. In contrast, the total number jobs in the state grew 13.3 percent during the same period.

The Bay Area, long a hub of university research and venture capital funding, has benefited more than any other part of the state. And yet other places, such as Orange County and Sacramento, have succeeded in luring and nurturing young green companies, to the point that each area has developed its own specialties.

The Bay Area, for example, leads the state in the number of jobs related to energy-generation technologies, such as solar and wind power, with a total of 7,003 positions. But the Los Angeles area has the most jobs related to green transportation, with 1,072 people working on alternative fuels or advanced vehicles.

"It's not like everybody has to do the same thing," said Doug Henton, chief executive officer of Collaborative Economics. "Every region - Sacramento, Southern California, even Sonoma - everyone's trying to develop some kind of economic strategy to their advantage."

Perhaps the study's most surprising finding is that manufacturing accounts for a significant portion of the state's green jobs, about 21 percent. Although many green companies are research startups whose products haven't yet left the lab, others have moved on to mass production.

For example, solar panel manufacturer Solyndra Inc. started construction of its second Bay Area factory in September, helped by a $535 million federal loan guarantee.

"At a time when we're worrying about whether we can hold onto manufacturing jobs, it looks like we have an opportunity here," Henton said.

In addition, the green economy may have benefits that extend beyond the number of new jobs generated.

Stephen Levy, director of the Center for the Continuing Study of the California Economy, noted that much of the green economy will consist of companies changing how they operate and what they make, offering products and services that help the environment and cut energy costs.

Some of those jobs will be new, while others will simply be existing jobs given a different purpose. Even if they aren't new, those jobs can still help the overall economy by helping consumers and companies save money on energy bills.

"I don't want to count it as job growth, but I also don't want to ignore the benefits," said Levy, who was not part of the Next 10 study. "You're going to have benefits to consumers and the planet."