How Does a Solar Water Heater Work?

Homeowners all over the nation are turning to solar power as an alternative source of energy for their home's electric appliances, such as water heaters. Many people choose to use solar power as a means of lowering their utility bills, while others are more interested in reducing their carbon footprints.

Introduction

Solar water heaters are very simple to understand at their most basic level. They are essentially holding containers covered with a material that harnesses radiation from the sun and converts it to heat energy. That heat energy is then absorbed by water, thereby raising its temperature. The hot water is then transported throughout the home by a variety of different methods. There are many different types of solar water heaters that share several components, but also differ in several aspects of their operation.

Types

Passive Solar Water Heater

This type of water heater is called passive because it in no way relies on electricity to heat or transport water. There are two common designs of passive solar water heaters; the batch solar water heater and the thermosiphon water heater. The batch water heater is the simplest and acts just as the heater described in the introduction. The thermosiphon solar water heater consists of tubes covered with materials that absorb solar energy, water then flows through the tubes and is warmed before being transported to a new tank.

Active Solar Water Heater

Active solar water heaters function similarly to passive solar heaters, except that they use electricity to transport the water that is being heated. There are two major types of active solar water heaters; direct water heaters that transfer energy directly from the heater to the water and indirect heaters that heat a separate fluid, which is then passed through tubes that allow the surrounding water to absorb the heat.