The islands that ship in their power
Hawaii is warm, sunny and sitting on volcanoes. So why does it run its lights mostly on oil that crosses an ocean in a tanker?
Hawaii is a chain of islands out in the middle of the Pacific. No power line and no fuel pipeline reaches them from the mainland, and each main island runs its own separate grid — so an island can't borrow electricity from a neighbor the way Ohio can borrow from Indiana.
Basis: Well-established: Hawaii's electric systems are island grids with no connection to any mainland grid or interstate pipeline.
That leaves ships. On this site's official EIA data, Hawaii makes more oil-burning electricity than any other state — and oil is more than 70% of Hawaii's own electricity, which arrives across the ocean in tankers.
Basis: This site's EIA quiz (machine-checked): Hawaii is #1 in petroleum-fired generation, and petroleum is over 70% of the state's total net generation. Hawaii has no mainland grid or pipeline connection, so power-plant fuel comes by sea.
Hawaii sits on volcanoes, and hot rock underground can boil water into steam that spins a turbine — the islands really do tap that heat. But on the same official data the Earth-heat champion is California, where a field of plants called The Geysers has been running since 1960; Hawaii is only #4.
Basis: This site's EIA geothermal quiz (machine-checked): California #1, Hawaii #4. The Geysers' first power plant began operating in 1960.
So why oil, and why not just sunshine? A tidy idea: oil is easy to carry in a tanker and easy to keep in a tank until the evening rush, while the sun sets every night and an island can't borrow power from next door when it does — so somebody has to keep a fuel that still works at 3 a.m. It fits, but fuel choices also follow money, history and rules, and big batteries are changing the picture fast.
※ A hypothesis is an idea that isn't proven yet.
📊 Sources for the rankings mentioned in this note (links to the original data and retrieval dates) are on each quiz page below.