Types of collectors in solar water heating system

Solar water heater comes with varieties of design including collector and storage tank. Solar water heating systems use solar panels, called collectors, fitted to your roof. These collect heat from the sun and use it to heat up water which is stored in a hot water cylinder and used. Rather than burning fossil fuels such as natural gas or fuel oil to heat water, consider tapping into the free, limitless energy of the sun to heat water for your commercial building.  A solar hot water system is a zero-emission, zero-waste solution to the problem of environmentally destructive water-heating methods. There are different types of collectors are available for solar water heater, each possess various benefits in solar water heating system.

#Flat plate collectors:

Flat plate collectors are most common and widely used in style of solar thermal collector for domestic hot water applications. The design is very simply an insulated box with an absorber sheet welded to copper pipe that the heat transfer liquid circulates through. There are differences in aspects of the design that can improve performance, make the panels lighter, easier to install and suitable for different installation formats, and ultimately impact on the cost, efficiency and longevity. Flat plate collectors are typically sized to contain 40 gallons of water.Two collectors provide roughly half of the hot water needed to serve a family of four.

The flat plate panel design utilizes many different absorber configurations with the main design being the harp configuration. The harp design is usually used in low pressure thermosyphon systems or pumped systems. The main advantage of flat–plate collectors over evacuated –tube one is price, the recent trends in evacuated-tube technology closed part of the gap, flat plate solar collectors are still a cheaper solution.

#Evacuated tube collectors:

The evacuated tube thermal collector is a more recent development than the conventional and more common flat plate collector. They have become more and more popular, particularly the reduction in their supply costs, their high performance and reliability in cold climates and commercial applications, and of course their attractive appearance. An evacuated solar system is the most efficient and a common means of solar thermal energy generation with a rate of efficiency of 70 per cent.

 There are two main types of tubes that are used inside the collector which are glass-glass and glass-metal. The glass-glass version uses two layers of glass fused together at both ends. The double glass tubes have a very reliable vacuum but reduce the amount of light that reaches the absorber inside. The double glass system may also experience more absorber corrosion due to moisture or condensation forming in the non-evacuated area of the tube. The second kind of tube is a glass-metal combination. The glass-metal combination allows more light to reach the absorber and reduces the chances of moisture corroding the absorber.

#Integral collector: 

Integral collector storage units are one of the simplest solar hot water heating systems available and can be easily installed into any conventional water heating installation. The main advantage of an integral collector storage system is that they do not need controls, pumps, sensors, or any other mechanical or moving parts, so maintenance requirements are minimal. Most of the ICS units produced today are progressive tube type heaters as opposed to the older single tank in a box type batch collectors making them less expensive than active solar systems. Integral collector storage systems depend on system demand for their flow; some models have been configured to use the thermosyphon principle. The thermosyphon system uses the principle of natural convection of fluid between a collector and an elevated storage tank. As water is heated in the collector and it rises naturally to the tank above. To know more details about solar water heater visit http://www.glazerindia.com/