Solar photovoltaics under the gun

It began a few weeks ago when San Francisco Mayor Gavin Newsom addressed a gathering of cleantech leaders.

"We need to stop playing at the margins," he said, in an impassioned call-to-arms at an event called Cleantech Crossroads (see the Cleantech Group's Bay Area cleantech leadership at risk, says Khosla.)

He urged those in the room to look beyond simply putting solar systems on roofs and think about more meaningful ways to address climate change.

Not that there was anything wrong with solar photovolatics, Newsom said. Or hybrid vehicles. Or phasing out petroleum-based plastic bags at retail, as San Francisco has done. But they were weren't, by themselves, meaningful activities, only "in the margins."

Newsom challeged attendees to help effect more dramatic changes, quickly, to help reverse global warming.

Today, at the micro-investment bank ThinkEquity's ThinkGreen conference in San Francisco, that same criticism was levied specifically at solar photovoltaics (PV), which raised the ire of vendors of the various silicon, thin film and other PV technologies.

The most provocative criticism came from investor Vinod Khosla, who, in a lunch keynote, called PV deployments too little, too late.

"Solar is not a climate change solution. That doesn't mean it's not a good investment. It's just not a climate change solution," he said, arguing the total amount of installed photovoltaics would never constitute a meaningful percentage of the world's energy mix.

Large scale solar thermal, said Khosla—an investor in solar thermal company Ausra—was the only viable approach to displace coal in significant enough quantities to help reverse the effects of climate change.

Ausra President and CEO Robert Fishman claimed at the conference that his company was in discussions to install its equipment at decomissioned coal plants and turn them into solar powered plants.

He said there was room for everybody in the renewable space.

"The renewable portfolio standard is large. The market demand is probably larger. There’s room for PV, there's room for solar thermal. If we're going to solve the global warming problem, we need a lot of solutions, not just one."

His view was echoed by Steve Eglash, CEO of multi-junction solar cell maker Cyrium Technologies, pursuing high performance solar cells like Boeing's Spectrolab.

"We’re still a long way from solar being even one percent, let alone 10 percent of the world's generating capacity. Solar is not a solution for the whole problem, but it's certainly a solution for an important piece of the problem."

Tim Teich, VP of sales and marketing of thin film maker Global Solar Energy was more heretical.

"I don’t subscribe to the climate change theory. I may be an apostate in this room. I'm in business to make money, and that's what we have to drive towards or we won’t be here to change climate."

Some industry observers were more charitable.

"It's absolutely a way to change climate. Even if [solar PV] displaces only 10 percent of coal use, it's still meaningful," said ThinkEquity research associate Peter Peng.

ThinkEquity greentech managing director Jonathan Hoopes summed it up, noting, "let’s not forget that Vinod’s background was highly successful thanks to heterogeneous IT environments. It’s not a one-solution-fits-all."

The conference concludes tomorrow.