John Doerr's long view talk at today's MIT Energy Conference gave a brief glimpse into how the VC approaches investing in such a crowded market. Following in the mold (one which Doerr himself helped to create) of the big money guys suddenly so worried about the future of our planet, Doerr started out with some big numbers. In the next 40 years, he said, the global population of city dwellers will skyrocket to nearly 6 billion people. "By 2050, that's the equivalent of 40 new megacities" or "like eight new Manhattans a year." What's more there are "two billion people coming on to the world's economic stage and they all want the same thing: clean energy and clean water." And, of course, Doerr has the solution. His concerns - prompted by the words of his two daughters - are speed and scale. How do we build a new energy infrastructure fast enough and big enough to meet the challenge? Well, says Doerr - quoting Billy Joy - "to fund the future you have to find it." When thinking about his investment criteria, Doerr pulls up a big map of the United States's energy infrastructure - it helps him think about where energy comes from, where it's going, and how it gets there. According to Doerr, "more than 55 percent of the energy for electricity is wasted in heat and transmission." This brings him to "cars, coal, and conservation - the three 'C's'." Following these ambiguous investment criteria, Doerr and Kleiner Perkins have invested close to $500 million in 30 greentech companies. These include Fisker, which is producing a vehicle Doerr claims "is going to be the first volume plug-in hybrid in the world when it goes into production next year." Also on the list is Miasolé, whose CIGS cells hit costs of "$0.12/kWh that costs less than $1 per watt peak." Or it would, if only the company could get its sputtering process right. But these are only a few solutions... "We've got to tap the world's capital," says Doerr. "Energy is a $6 trillion a year business, and I like to say it's the mother of all markets." But what about all the venture capital going into greentech? Doerr "thinks we'll see venture capital respond to the size of this opportunity, especially as we see more large, venture-backed public companies. And I think we'll see those in 2009. " When asked if he thought the money flowing in to greentech - over $4 billion in North America during 2007 - was creating a bubble in the market, Doerr responded "I can assure we do not have an over investment against the scale of this problem." Doerr thinks the scale of returns in greentech "are possibly an order of magnitude higher" than in IT. So, if you want to get in on some of that action, email John at jdoerr@kpcb.com. I'm sure he'd love to hear from you.