According to Clean Edge research, the top 15 metro areas in the U.S. for clean-tech job activity, based on an analysis of job postings, investment and patent activity, and other data, include the San Francisco Bay Area at #1, Greater Boston/southern New Hampshire at #4; Denver/northern Colorado at #6; Austin-San Marcos, Texas at #12; and Detroit-Ann Arbor, Michigan at #14. (Complete results availa