Hawaii's sunny, mild climate gives it a leg up over many states. Home to the nation's highest electricity rates, the state has proved to be a magnet for smart-meter installers and other energy efficiency companies. That push for consumption reduction means Hawaii has the second-lowest electricity use per capita behind California.
Clean-tech job growth has been rising steadily over the past 10 years, according to state data. Also, 26 percent of construction expenditure in Hawaii in 2012 was solar-related. Hawaii's solar-energy capacity jumped 150 percent in 2011, making it No. 11 among the 50 states in terms of solar capacity, according to the US Energy Information Administration (EIA).