The State and City/County of Honolulu used to offer some nice perks for EVs, including free parking at the airport, but let most of them expire about 2 years ago. The other odd thing for charging is the power company on Oahu offers a program which gives a good discount from 9 AM-5 PM , very high rates from 5-10 PM and standard rate the rest of the time. The reason for the daytime discount is they have surplus solar power during the daylight hours.