Is a home battery worth it in Hawaii?

Almost every explanation of home batteries you will find was made by someone selling one. So here is the version from people who are not. A home battery does three things. It keeps your lights on when the grid goes down. It buys electricity when it is cheap so you can use it when it is expensive. And it can earn you money by letting the utility borrow it. In most states only one of those is worth real money, and it is usually not the one you called about. Start with backup. A mainstream battery holds about thirteen and a half kilowatt hours. Run a fridge and some lights, about a quarter of a kilowatt, and that lasts you roughly two days. Back up your whole home's essential circuits instead, around two point two kilowatts, and the same battery gives you about six hours. Same battery, same kilowatt hours. The only thing that changed is what you asked it to carry. Anyone quoting you days of backup without asking what is plugged in is guessing. Second job: buying low and using high. This one only works if your utility charges different prices at different times of day. In California the blended average is about thirty-four cents a kilowatt hour. Peak can pass fifty-five. Off-peak can drop under twenty-five. That gap is the entire business case. Charge at twenty-five, use it at fifty-five, keep the difference. In Texas and Florida, at about fifteen cents flat, there is no gap to work with. The battery still runs. It just is not earning. Third job, and the one most people have never heard of. Your utility may pay you to let them borrow your battery during a grid emergency. These are virtual power plant programs. In California that runs four hundred to fifteen hundred dollars a year. In Texas and Florida, for a residential customer, it mostly is not available yet. Then the rebates, which is where the real money is, and where the bad information is worst. California's SGIP pays a hundred fifty to two hundred dollars per kilowatt hour, and up to around a thousand if you are in a high fire-risk area or on a medical baseline. Now the federal credit, and listen closely, because this is the one that gets sold wrong. The thirty percent that homeowners used to claim directly on their own taxes is gone. There is still a thirty percent credit, under Section 48E, but on a lease or a power purchase agreement it is the company that owns the system that claims it, not you. They may pass some of it back as a lower price. That is a different thing from a check from the IRS. If someone selling you a battery says you will get thirty percent back on your taxes, they are describing a program that no longer works that way. So, is it worth it? It comes down to your state, how your utility prices power, and what you actually need to keep running. Those three things, in that order. We track incentives across twenty-seven states and we put a verification date on every number. Check yours before you take anyone's word for it. Including ours.