He did not say who would pay for a technology which increases the cost of powergeneration so much that it has still not been adopted in rich nations which have caused the climate problem.
Projects like powergeneration, on the other hand, may cost hundreds of millions of dollars, since Google.org will endeavor to prove engineering concepts by building out power plants.
And developing basic low-cost pollution technology for coal-fired powergeneration in the third world would probably get more bang for the pollution buck than just about anything else.
Unfortunately these arguments rarely acknowledge the need to contextualize the cost of administering these subsidies in the current regime of centralized government-dominated powergeneration and transmission.