If you’ve spent any time in the electrification world, you’ve likely heard of heat pumps. You know they move heat rather than creating it, and you know they are the undisputed kings of HVAC efficiency. But when we transition from space heating to domestic hot water (DHW), the engineering challenges shift. At one-fifth of home energy usage, it's the biggest energy guzzler that nobody talks about.
Enter the Heat Pump Water Heater (HPWH), the next frontier of home electrification.
In this article, we break down the fundamental technology of how HPWHs work, how they compare to other types of water heaters, and common consumer pain points. Once we cover the basics, we’ll explore how next-generation HPWHs, like Reservoir, are moving beyond simple hardware into predictive, grid-connected systems.
