Solar power

For firefighters, there can be too many solar panels on a roof. Fire officials and the solar industry are paying attention to the concern.

Rooftop solar installations cut into utilities' revenue, but still use their expensive grid and and rely on them for backup power.

Solar facilities like Ivanpah could be the future -- or, they could be a footnote in the history of clean energy.

European -- and some American manufacturers -- believe Chinese solar panels are being sold for less than they cost to build. The European Commission is investigating, but now Germany is distancing itself from the "dumping" allegations.

The U.S. believes China is dumping solar panels at below-market prices in America and has hit back with a penalty of 31 percent. That tariff is surprisingly steep and many in China are not reacting well. Could they backfire?

The U.S. will impose new tariffs on cheap Chinese solar panels. The new duties will be low. Analysts say it's not likely to spark a trade war.

The solar sector in the U.S. did very well in 2011, installing nearly twice as much capacity as the previous year -- a record. And the industry still expects to have an even better 2012.

The state visit by Chinese VP Xi Jengpeng highlights U.S.-China cooperation -- but behind the scenes, China plays hardball.

Solar stocks have been plunging of late and the world's biggest solar market is tapping the brakes on sun power. Looks like a cloudy forecast ahead.