> Heat pump water heaters are drastically more energy efficient. And also don't work in most of the United States. They are very slow, and only work in places

> Heat pump water heaters are drastically more energy efficient. And also don't work in most of the United States. They are very slow, and only work in places with warm climates - in cold places they are dumping their cold into the living area, which then has to heat it. On top of that the incoming water is cold, and they don't do a good job heating it. I've looking into buying one, and they just don't work in cold climates. They could work in California, true, but are they mandating that? Nope. They are just eliminating gas.