Let’s Clear Up Some Confusion About Solar Panels – Via Houzz.com
Different panel types do different things. If you want solar energy for your home, get the basics here first.
- It can provide power, in the form of solar energy converted to electricity, or
- It can heat water, through direct or indirect solar radiation.
Panels that provide electrical power are photovoltaic (PV for short). Panels that heat water are often described as solar thermal collectors.
It gets confusing because we sometimes shorten “solar thermal collectors or panels” to “solar panels” in conversation, and that is easily mixed up and used interchangeably (even by professionals) with “PV panels.” But it’s important to understand that the work the solar energy does in both kinds of panels is different. In the first it provides electricity. In the second it heats up water.
Many people wonder, “When I see a house with a bunch of panels on the roof, what am I looking at?” Well, let’s take a look.
In this photo we’ve got a side-by-side comparison of the two. In the center are two darker panels. These are examples of one type of solar thermal panel, which is used to heat water.
Surrounding them you can see many photovoltaic (PV) panels. These are used to convert solar power to electricity. That electricity may be used for many things, including heating water in a more conventional electric system.
There is another kind of solar water heater, known as a batch system. However, this is not used frequently here in Europe due to its susceptibility to freezing temperatures and lower efficiency. Even in the U.S. (as we saw this year with the phenomenal polar vortex), there are few places with no risk of freezing temperatures.