Solar Water Heater Basics

A solar water heater is a smart and simple alternative to heating your home’s water supply. Since the magic behind these units is the sun, they have always been an attractive alternative to a conventional gas or electric water heater. They come in varying sizes, dependent upon the need and can be used in just about any part of the world. Occasionally you will find these units working by themselves, but many times they are part of a complete alternative energy system.

The make up of a solar water heater is relatively simple. Regardless of the design or type, they all have a single purpose; harness the sun’s energy to heat water. An easy way to understand a solar water heater is to think about a car radiator.

A car radiator has a network of coolant pipes that run throughout it which contain an antifreeze/water solution used for cooling the car engine. These pipes are positioned within the radiator so that air passes over them and cools the solution running through them. This solution is circulated throughout the engine block by a water pump. A solar water heater works in a similar way.

A solar water heater has a network of piping that contains fresh water or an antifreeze solution circulated by a pump. These pipes flow through a “collector” that is positioned to absorb direct sunlight. If a system is set up to circulate fresh water, then the output of the collector (heated water) is typically sent to a conventional water heater tank for storage and maintenance of the temperature until its needed.

As mentioned above, an alternative design is to circulate an antifreeze type solution through these pipes. In this design, the heated solution is sent to a heat exchanger. The heat exchanger is where cool, fresh water is passed over the outside of the pipes containing the heated solution. As the fresh water passes over these pipes the heat is transferred to it. This heated fresh water is then pumped out to where it can be used.

As you can see, a solar water heater is a simple unit. There are many other designs, each with a specific application, but overall they all have the same end result. In my research I found plenty of manufacturers and distributors that sell these units for a variety of environments. What intrigued me however, were the do it yourself kits that teach you step by step about the construction of a solar water heater. I ended up purchasing and reviewing a couple of these guides for my personal interests and found them extremely valuable.

If you're interested in learning more about do it yourself, solar water heater instructional guide, I strongly recommend you read my review of: