Heat pump water heaters become the default choice

Why your next water heater should be a heat pump

Heat pump water heaters do a magical thing: they move heat from the air to the water inside a tank. They heat water cheaply, at low carbon impact, and with low impact to the grid. And because of that, California policymakers are offering huge incentives to install them.

Here's a digram about how heat pump water heaters work. There are two basic elements:

1. A heat pump on the top extracts heat from air and transfers that heat into a hot gas. It's basically an air conditioner run in reverse.

2. A loop passes that hot gas in a pipe through a tank of water. When the gas pipe runs through the water, the heat transfers to the water in the tank, and the gas turns to a liquid, going back through the heat pump to begin the cycle again. The hot water then runs into your pipes for showering, dishes, etc.

Pumping heat from air to water turns out to be much more efficient than running water through a natural gas burner, or using an old-school electric resistance coil to heat water. This is especially true in a mild climate like California, where outdoor air is generally above freezing, and nearly always above zero degrees Farenheit.

Carbon impact of heat pumps is also much lower than that of gas or electric resistance heat. Partly that's because heat pumps are more efficient. And part of it is due to California's clean electric grid. This grid is finely balanced and is sometimes

The huge advantage of heat pump water heaters for the grid is that they can be timed to run when they won't impact the grid. They can run at peak solar times, or be set to shut off when the grid is under stress. Because water is stored in a tank, you won't notice the difference in your typical daily use.

Water heater carbon impact matters – about a quarter of a home's carbon impact is due to water heating.

Because of the carbon impact and the grid-friendly nature of heat pump water heaters, policymakers have heavily incentivized their install. Here's an example of the incentives a California resident could take advantage of:

• $400 rebate from BayRen (or your local agency)

• $3,100 from TECH Clean (state program)

• $1000 instant discount to your contractor from BayRen (or local agency)

• $2000 tax credit from the IRS (up to 30% of project cost)

With heat pump water heaters costing $3,500 to 5,000 to install, including labor and materials, incentives and tax credits will cover the entire cost of install.

Go to it and let us know if you have any questions. We're happy to point you to our trusted contractors if you're looking for an install partner.