Scoring 74.49 overall , Hawaii ’ s capital ranks first for environment , 14th for lifestyle and policy , 21st for energy sources and a middling 38th for transportation . The city is working to prevent further water pollution , mainly by promoting permablitz ; a movement involving volunteers who plant permaculture gardens in order to reduce storm water runoff . Honolulu also currently has the most solar power per capita in comparison with all other US cities . 34 October 2017