Applications of solar Energy: Solar Water Heater

Posted by admin on Jan 23, 2014 in Posts

As we are in the twenty first century, the cost of non renewable sources of energy is enhancing every day. In such a scenario, solar water heaters are in high demand.

Solar water heaters are being used worldwide especially in India, US, China and many other African countries. US was the first country to utilize solar power to heat water. It has gained popularity as it is very much economical than fossil fuels. However in earlier days when the price of fossil fuels was not that much, it was not in demand at that time.

Types of solar water heaters

Usually there are two types of solar water heaters. They are an active type and passive type. The only difference between them is the way the liquid is circulated inside them; an active consists of circulating pumps and controls, whereas a passive is much simpler in design and working. This article will go deep into Active solar water heaters.

Types of Solar panels

Three different types of solar collectors are used in solar water heaters. They are Flat-plate collectors, Integral collector-storage system and evacuated-tube solar collectors.

1. Flat plate collectors- These collectors are flat in shape and consist of different layers of surfaces. A layer of glass or plastic is placed at the top where the sunlight falls. The box of the collector is properly insulated and weather shield and is the most common collectors.

2. Integral collector storage system-These collectors are being used in cold areas where there is not sufficient solar energy available to heat water. In such collectors, the water is first heated and then passed to the tank and after that it is again heated by a heater in order to get good quality of hot water.

3. Evacuated-tube solar collectors-In such solar collectors, there are many tubes, which are made up of glass and metal and positioned in such a manner that every glass tube is parallel to each other. The tubes are located so that direct sunlight falls on them. The outer part of the tube is made of glass, and the inner part of the glass is made of metal. The metal part plays the role of absorber which absorbs heat. Such types of solar collectors are installed in the place where there is an adequate supply of heat which can be absorbed. It also helps to reduce the loss due to radiations.