Well, on Maui that’s not as feasible, because such activity is now minimal and far underground, and has mostly moved to creating the big island.

Oahu is even less active than Maui, being farther back in the island creation path.

On the big island it would be more feasible with the active volcano, but would likely have to restrict it to capturing what you could from steam vents (which aren’t that plentiful, even around the volcano rim). Trying to build something over the areas active enough with lava would probably just be asking for the occasional eruption with ejected plumes destroying the investment. So solar and wind are still our better options because those resources are in excess without melting anything down.

I think the main reason that coal and oil were/are still being used is simply because that’s the working infrastructure that was already there. Wind turbines have been added to slowly replace part of the need, as well as solar on housing to reduce those residents’ bills and feed back into the grid, but the larger move to solar farms has (I believe) been waiting for the solar and battery tech to get better before spending our level of expense on it. And probably determining where to put farms that are large enough. There’s a lot of concern about placing such things on burial grounds, and on such a small pieces of land it can be a challenge to find large suitable areas that don’t also contain ancestors. Hopefully here on Maui they’re planning to use part of the central valley for it now that cane is no longer grown, but idk.