An ocean apart from the US mainland’s electric supply, Hawaii has embarked on an ambitious effort to wean itself off imported fossil fuels with a mandate to reach 100 percent renewable electricity by 2045. Elemental Excelerator commissioned Rhodium Group, in partnership with Smart Growth America, to conduct an independent analysis of Hawaii’s clean energy transition. This is not a plan; rather, this report presents a quantitative assessment of accomplishments to date and describes the future potential of clean energy deployment in Hawaii’s electric power sector and on-road transportation.