Innovation hubs are key to driving the next generation of technology — and making a lot of people a lot of money. For years, Silicon Valley has offered the combo of nearby university talent, investment funds, a networking environment and local regulations that promote startups. But when it comes to cleantech in the U.S., incubation centers are spread out across the country. Over on Earth2Tech we have put together the Top 7 Cities for Cleantech, those that offer the most nourishing climates for entrepreneurs, students and investors. The list is led by cities with progressive mayors, programs that offer incentives to keep businesses within the urban area, and green buying habits, like buying green cars for city fleets, or making city buildings LEED-certified. OK so San Jose and San Francisco are still way up there, but find out which are the other five on Earth2Tech.