As we reported earlier, Germany just brought online the world's largest solar plant. While a big deal in itself, the Mulhausen plant really just signals a larger trend.
Germany is the fastest-growing market for photvoltaics in the world, worth over 800 million euros (well over one billion dollars) last year, and an estimated 1.8 billion euros in 2004. The German solar industry is already generating 400 MW, more than the rest of Europe put together. (It doesn't stop with solar: as Jamais reported, "Germany is also the world's leading producer of wind power, with over 16,000 windmills; power generation capacity from wind amounted to 14,609 megawatts in 2003, up from 334 megawatts in 1993.")
These strong numbers are in large part a result of the German Renewable Energy Law (EEG), which levels the playing field by tilting subsidies away from fossil fuels and towards renewables.
Less noted is Germany's strong commitment to energy efficiency and green design, like the CO2 Building Modernization Program (PDF), which is investing 360 million euro a year in green building retrofits (borrowers who meet particularly high standards only have to back 80% of the loan).
According to Michael Rogol at a lecture at MIT a few months ago, Germany is the biggest PV market, Japan is next and California is third, maybe.
Rogol's investment report on the world solar industry is at http://www.photon-magazine.com/news/ww%20ms%20Sun%20Screen%20Studie.pdf
FYI, to clarify, Japan is world's largest market, Germany #2, California #3. - rogol