Solar Components For Solar Water Heat

Several solar components make up a system for solar water heat: solar heating panels, solar storage tank, solar heat exchanger, and solar controls in some systems.

Solar Heating Panels

The basic types of solar heating panels, also called solar collectors:

• Flat Plate Solar Panels
• Evacuated Tube
• Unglazed Swimming Pool Heater

Solar Storage Tank

The storage tank and backup water heater stores the heated water until used. A well insulated storage tank stores hot water for extended periods until used for domestic or other uses.

When the solar heating panel is unable to heat as much water as needed, the conventional heating methods heat the water. The solar hot water heater can meet up to 80% of your hot water needs.

Most solar hot water systems have one solar water storage tank. This tank is equipped with an auxiliary heating element. This provides additional heating when required.

A double tank system uses one tank exclusively to store heated water from the panel. This tank does not use any auxiliary heat.

This tank is plumed to a second tank, a conventional water heater. Solar heated water is moves to the conventional water heater when required.

When water temperature drops below a specified point water is heated using conventional methods.

Some solar hot water system use double tanks. The first tank receives solar heatedwater from the solar panel. This tank holds the heated water until needed.

The second tank is a conventional hot water tank that receives pre-heated water from the first tank.

If water from the first tank cools the conventional water hater has an element to bring water temperatures to the desired temperature.

Solar Heat Exchanger

The heat exchanger transfers heat from the heat transfer fluid to the potable water supply in the storage tank.

Usually water or a water and glycol antifreeze mixture makes up the heat transfer fluid.

Solar heating system heat exchangers are generally made of copper for its heat transfer efficiency and resistance to corrosion.

Solar Controls

The solar controls directs the components in the solar water heater system to control pumps moving fluid through the system when required.

Differential controls work with two sensors – one located at the hottest point in the solar heating panels and the other at the coldest location in the storage tank.

When the temperature reaches a set differential the controller turns the pump on or off.

In some systems, a photovoltaic control next to the solar collector provides DC power to a DC pump.

The controller turns the DC pump on or off for optional operation of the system. The controller operates other valves and gauges.

This assures optional operation of the system.