Answering 2 Commonly Asked Questions About Solar Hot Water Heaters

A solar hot water heater is a great way to cut down on your energy use, as the hot water heater is often one of the largest consumers of electricity in many homes. If you're thinking of installing a solar system for your hot water heater, note a few questions you might have and then discuss this option with a contractor as needed.

What is the difference between tubes and panels?

When shopping for a solar system, you may see evacuated tubes versus flat panels. The evacuated tubes capture heat from the sun and trap it inside insulated tubes, and this heat is then pulled from the tubes by a vacuum that is formed between them. The heat is transferred to your water heater, where it then heats the water stored in the tank.

Flat panels capture sunlight from the sun, and then wires inside the panels convert this light into the type of energy you use to power your hot water heater. This electricity is stored in batteries, not the panels themselves, which are connected to your home's electrical system.

Both systems have their own pros and cons; tubes may be larger and more conspicuous, so they may not work well for a smaller home or condo. Flat panels can be installed on a roof or even as stand-alone panels in your yard, so they're better for small spaces. However, the tubes may be easier to repair when needed, as the wiring and materials of the flat panels may need the assistance of a specialized technician when they're damaged.

Does solar power work in cold weather?

Note that the power from solar during wintertime will depend on the type of system you choose and the water heater itself. Tubes have specialized insulation that keeps the heat it traps inside, so they may lose some stored heat, but not all, in colder weather. Solar panels work to convert sunlight, not heat, into electricity; these panels charge the batteries that store power, so as long as there is sufficient sunlight, the cold weather shouldn't affect them.

However, if you should notice any loss of hot water during wintertime or that your water heater needs to switch to city-supplied power quite often, you may have a very large unit that simply requires more power than your solar system can provide. In this case, you may need to reduce the size of the heater or upgrade to larger tubes or panels.