Hopefully you have self-sufficient solar with any plug-in Oahu. Oahu is shutting down their remaining coal power plant this year to make deadlines set by the state; unfortunately, greener projects are delayed and won't be online in time to make up for demand. As such HECO is getting ready to ramp up oil burning power plants which cost 4x+ more to operate than coal and expect to pass those costs onto consumers. So if you don't have solar, the calculus on saving gas money with an electric car go out the window in Hawaii due to the even more expensive electric rates.

I have a Tesla and a personal solar system that produces far more than the house and car consume, so I'm in a sweetspot where I'm immune to high gas and electric rates. But most people aren't as lucky especially those on Oahu.