Welcome to the end of that caveat. From ScienceBlog:
Two technologies have dominated efforts to harness the power of the sun’s energy. Photovoltaics convert sunlight into electric current, while solar-thermal power generation uses sunlight to heat water and produce thermal energy. Photovoltaic cells have been deployed widely as flat panels, while solar-thermal power generation employs sunlight-absorbing surfaces feasible in residential and large-scale industrial settings...“We have developed a flat panel that is a hybrid capable of generating hot water and electricity in the same system,” said Ren. “The ability to generate electricity by improving existing technology at minimal cost makes this type of power generation self-sustaining from a cost standpoint.”
This is huge. I'm still primarily a supporter of smart and careful nuclear power, but this development bumps solar far up the ranking of viable energy sources.