Research house iSuppli Corp also expects the Golden State's hot-streak to continue in 2010, when California's photovoltaic installations, in terms of megawatts of power generated, would increase another 68 percent, while solar panel installations around the world grow 54 percent.
The solar power industry has suffered in the credit crisis, which has dried up available financing for new projects and a dramatic fall in solar panel prices has cut into companies' profits.
This year, iSuppli expects panel installations to jump 120 percent in California, compared with a 27 percent global decline.
Henning Wicht, senior director and principal analyst for photovoltaic at iSuppli, attributed California's growth in solar installations to the state taking advantage of incentive programs such as the federal solar tax credit and U.S. stimulus program.
"This is a very encouraging sign for the solar market," Wicht said in a statement.
ISuppli expects California to install 350 megawatts of solar systems in 2009, compared with 132 MW installed across the rest of the United States. California ramped up on Tuesday its goal to have 33 percent of its energy come from renewable resources by 2020, up from a previous target of 20 percent by 2010.
Worldwide, iSuppli estimates 4 gigawatts of photovoltaic systems will be installed in 2009, with Germany adding 1.5 GW and Italy 580 MW and another 300 to 400 MW coming from Spain and Japan each.