So far just 3 percent of Germany's electricity comes from the sun, but the government wants to raise the share of renewables to 27 percent of all energy by 2020 from 13 percent.

It is a thriving industry with booming exports that has created tens of thousands of jobs in recent years, posting growth rates that surpassed the optimistic forecasts made by the fathers of a pioneering 2000 renewable energy law.

This law, known by the acronym EEG, has helped this cloudy, rainy country on the northern rim of central Europe become a solar giant.

"The EEG was the single most important vehicle to boost the solar energy market," Frank Asbeck, chairman of SolarWorld AG, told Reuters. The law, which offers cash incentives to people introducing renewable energy sources, was designed to help fight climate change and reduce dependency on fossil fuels.

"There has also been an enormous interest for solar power from the public in general," added Asbeck, who in 1988 started his Bonn-based company making and marketing PV products. Its 1,350 staff have doubled in number in the last two years.

"Germans have a fondness for inventing and developing technologies -- especially when it might lead to big export rates. Helping fight climate change is a bonus," said Asbeck, who plans to nearly double the staff again within two years.

LEGIONS OF HOMEOWNERS

There are now more than 300,000 photovoltaic systems in Germany -- the energy law had planned for 100,000.

Spread out across the country, they are owned by legions of homeowners, farmers and small businesses who are capitalising on the government-backed march into renewable energy.

By tapping the daylight for electricity -- which power companies are obliged to buy for 20 years at more than triple market prices -- they are at the vanguard of a grassroots movement in the fight against climate change.

"It's grown much faster than anyone thought it would," Juergen Trittin, the former Environment Minister who masterminded the scheme, told Reuters. He was mocked at the time for his claims it would create jobs and not hurt the economy.

There are now 250,000 jobs in Germany in the renewables energy sector. Asbeck expects the number of jobs in solar power alone to double to 90,000 over the next five years and hit 200,000 in 2020.

The law has also since served as a model for other countries including Spain, Portugal, Greece, France and Italy.

GUARANTEED PAYMENT

Germany's photovoltaic systems generate about 3,000 megawatts of power -- 1,000 times more than in 1990.

Asbeck said political decisions in the 1990s made it easy and even lucrative for ordinary people to put the systems on their roofs.

At the heart of the scheme is a "feed-in tariff" giving anyone who generates power from solar PV, wind or hydro a guaranteed payment from the local power company. The power firms are obliged to buy solar electricity for 49 cents per kilowatt hour -- or nearly four times market rates.

This can work out at a better return than putting money in the bank. So despite the cloudy weather, the investment pays for itself within 10 years.

There are some critics of the solar power incentives who want the government to phase out the programme faster than now planned. The lucrative feed-in-tariffs are, however, guaranteed for 20 years for all existing owners.

Gerhard Mueller-Westermeyer, a climate researcher at the German national weather service (DWD), said most of Germany is covered by clouds between five and six eighths of the time and there are only a handful of days each year with no clouds at all. Many German towns have annual sunshine of some 1,500 hours - about half as much as in Spain.