Calera

Vinod Khosla just might have let it slip which of his cleantech investments he thinks has the best chance at success.

When asked to pick the top company in the cleantech portfolio of Khosla Ventures, the firm's founder told the audience at the Always On Going Green Conference in Sausalito, Calif., that he couldn't choose (see Kleiner Perkins hints at plug-in car launch this week).

It's more than a battle of namesake between Vinod Khosla investment Calera (not to be confused with Caldera, which bought parts of Linux vendor SCO) and scientist Ken Caldeira; it's an accusation of fraud and misrepresentation… to children!

Sparked by a new exhibit at the California Academy of Sciences detailing the controversial Calera process, the conveniently confusingly-named Caldeira, a Carnegie Institution scientist who has studied this exact process, started a Google Groups discussion challenging the scientific claims of the exhibit.