Flat plate Liquid Solar Collectors

In active solar space heating, the collector is a main component in the process. There are different types of collectors, but for the purposes of this article, we are going to focus on the flat-plate collector.

What is a flat-plate collector?

Flat-plate collectors are actually quite simple. They consist of an insulated metal box covered with a glass or plastic cover called glazing. Within the box, is a dark-colored absorber plate that is made out of a metal heat conductor and painted black to absorb and trap more heat. The absorber plate then transfers the heat to either air or liquid. Lying beside the absorber plate, are tubes that contain either water or air.

How does a liquid flat-plate collector work?

A flat-plate liquid collector works by transferring the heat gathered from the absorber plate to the liquid flowing through the tubes attached to the plate. A pump within the collector re-circulates this liquid throughout the tubes allowing it to absorb as much heat as possible.

What is the difference between the two forms of liquid systems?

There can be two different forms of liquid systems: the open-loop system, or the type that requires a heat-transfer fluid. The open-loop system is the most direct. The water is heated and then flows directly to the point of use. The heat-transfer method requires the use of an antifreeze liquid that is heated from the collector and then moved to a heat exchanger. The heat exchanger is connected to a storage tank which uses the heated anti-freeze to heat water. This seems like an extra, unnecessary step; but in actuality, allows you to have more hot water readily available than the open-loop system. You can possibly have hot water after dark as well with the use of a storage tank.

If you are ready to save on your energy bill, a solar-heated water system may be a good place to start. Request free estimates from prescreened solar installers in your area.

Flat Plate Liquid Collectors / Flat Plate Air Collectors