How Do Solar Water Heaters Actually Work?

The solar water heaters are known for its simplicity and reliability. It helps you to use as much amount of water as the electric water heater offers. Before buying any heater, it is necessary to know that how the heater is working. It will get you to know entirely about the system’s right or wrong operations. Collectors used in water heaters are:

  • The Flat plate collectors– used with the storage tanks
  • The Evacuated tubes– employed in the colder regions

The Flat Plate Solar Collectors

The Flat plate collectors connected to the water reservoir. In this system, the copper pipes covered with a glass collector. The sunlight heats up the copper pipes and heats the water. When you open the valve, the hot water comes out of the storage tank.

The Evacuated Tube

The solar water heater consists of two Evacuated tubes in which the two glass tubes are merged at the top as well as at the bottom. The small space is remained between the tubes to form a vacuum. The pipe which is heated attached with the pumps with which the water circulates to a storage tank during day time. Due to the insulation of the shell, you can use the hot water anytime. In evacuated tubes, there is no need of direct sun rays as the tubes have the ability to pull out heat from the air even on a humid day. The space between the tubes helps to keep the water hot for all the time. So, the evacuated tubes are much more efficient as a comparison to horizontal cells. In evacuated tubes, the requirement of direct sunlight finished off.

But in the flat cells, the direct sunlight is required to keep the water hot which lasts for few hours. The water becomes cooler and cooler by the time. The repairing cost of evacuated tubes is lesser than the flat tube. When the heat in the tank increases up to a level, then the hot water comes out from the solar collector, when you open the valve. For the safety, the tempering valve attached to the position of your regular tap. The tempering valve reduces the temperature when it rises to 60 degree Celsius.

Gas and Electric Boost System

The solar water heaters provide you with the hot water with the help of sunlight. On the cloudy days, it becomes difficult to get hot water. So, the gas and electric boost system discovered to resolve these issues. The internal temperature drops down when the tank is heated. The shell raised only when the amount of hot water is less. There is no wastage of energy occurs.

Kit for solar hot water systems

The another electric tank can also act as a solar water heater as the retrofitting kit helps you to make it solar water heater.

The Approximation table for using the different heaters for various family sizes:


The solar water heaters are environment- friendly and provide the hot water at low cost without wasting any energy.