The combination of a heat pump water heater and photovoltaic system allows you to cost-effectively heat your water with solar power!
Our Solution for Domestic Water Heating
Heat pump water heaters have significantly improved in the past five years. These units draw heat from the surrounding air and transfer it to your domestic hot water. The Energy Star website has an overview of this water heating technology.
Although these do use electricity, they use a lot less than an electric resistance water heater. Adding 1.5-2 kW of capacity to your photovoltaic system will offset the electricity used by the heat pump water heater in a typical home.
For example, we had a customer that needed a new water heater. The family wanted a 2 kW photovoltaic system to offset 100% of their electrical load. We installed a heat pump water heater and an additional 2 kW of photovoltaic system (for a total of 4 kw), for less than half the cost of installing a solar domestic hot water system and backup natural gas water heater.
Why we don’t offer a completely solar water heating solution
Solar water heating systems can provide domestic hot water and contribute to space heating. However, at this time, solar water heaters are not nearly as cost effective as photovoltaic systems. The majority of homes and commercial buildings in the Madison area use natural gas or LP for heating the hot water.
The relative low cost of these fuels and the cost of installing hot water systems has pushed the return on investment out to well over 20 years. In contrast, many residential photovoltaic systems have a return on investment in the 10 year range and commercial systems in the 7 year range.