"The supergrid will be the last great network we build in our lifetimes," said John Doerr, partner at Kleiner Perkins Caufield and Byers who helped fund Google and Amazon.com but now focuses on green technology. The electric grid has "been a dumb one-way pipe, but it's about to get really smart with lots of apps," said Doerr in an on-stage interview at the Greenbeat conference here.

"Today the Internet represents a $1 trillion economy and there are some 1.2 billion people on the Net, but energy is a $6 trillion economy, four billion people use it and there hasn't been innovation here for a variety of reasons," he said.

Doerr was an early investor in Silver Springs Networks, a smart meter startup expected to go public next year. Earlier this year alternative battery maker A123 went public in a successful IPO that many market watchers say effectively opened a long-closed window for high tech IPOs.

After the interview, Doerr took questions from a handful of the estimated 400 attendees at the event. He discussed his views on a wide range of topics including everything from hot technologies to China's role in smart electric grids.

In the on-stage interview Doerr shared his experiences and opinions on lobbying for green technologies in Sacramento and Washington D.C.