The amount of electricity produced via rooftop solar panels in Los Angeles nearly tripled over the past two years, putting it within striking distance of San Diego, California's biggest solar-electricity producer, according to a report released today.

As of September, Los Angeles has 4,018 rooftop solar installations, second to San Diego's 4,507, according to the report by Environment California.

San Jose, Fresno and San Francisco rounded-out the state's top five solar electricity producers.

The maximum output in Los Angeles is 36 megawatts, slightly less than San Diego's 37 megawatts, according to Environment California.

Electrical current is measured in megawatts -- a million watts -- and kilowatts -- 1,000 watts -- and usage is measure in kilowatt-hours or 1,000 watts per hour. An average American household uses about 10,000 kilowatt-hours of electricity over the course of a year.

Los Angeles nearly tripled the amount of rooftop solar energy in the last two years to surge to the No. 2 spot in California, the report said.

Per capita, however, only about 1 in 1,000 Angelenos have rooftop photovoltaic panels.

"If the city of Los Angeles achieved the same levels of solar penetration as Santa Cruz and Chico, it would have more than 50,000 solar rooftops and 400 MW of solar power," the report said.

Germany now gets about 4 percent of its electricity from solar panels, thanks largely to a government incentive program that has helped create about 100,000 jobs over the past decade.