A solar collector is a device that collects and/or concentrates solar radiation from the Sun and convert into thermal energy that can be used to heat water, air or any media as per requirements.
Solar collectors are generally mounted on the roof and must be very sturdy as they are exposed to a variety of different weather conditions.
The use of solar collectors provides an alternative for traditional domestic water heating using a water heater, potentially reducing energy costs over time. Solar collectors are also used in thermal power plants to generate electricity. Based on the technology / characteristics solar collectors are categorised into three, flat type, Evacuated Tube(ETC) type and Concentric type solar collectors.
|MODEL||KE 2.0R||KE 2.5R|
|Gross area (m²)||2,09||2,49|
|Absorber area (m²)||1,92||2,31|
|Absorber volume (l)||1,37||1,64|
|Absorber type||High Selective||High Selective|
|Absorptivity||95% +/-2%||95% +/-2%|
|Emmisivity||5% +/-2%||5% +/-2%|
|Maximum Operation Pressure||10 bar||10 bar|
Evacuated Type Solar collector (ETC)
This type of solar collector uses a series of evacuated tubes to heat water for use. These tubes utilize a vacuum, or evacuated space, to capture the suns energy while minimizing the loss of heat to the surroundings. They have an inner metal tube which acts as the absorber plate, which (may or may not) connected to a heat pipe to carry the heat collected from the Sun to the water. This heat pipe is essentially a pipe where the fluid contents are under a very particular pressure. At this pressure, the “hot” end of the pipe has boiling liquid in it while the “cold” end has condensing vapour. This allows for thermal energy to move more efficiently from one end of the pipe to the other. Once the heat from the Sun moves from the hot end of the heat pipe to the condensing end, the thermal energy is transported into the water being heated for use..
Concentric Solar Collectors
These collectors, sometimes known as parabolic channels, use highly reflective materials to collect and concentrate the heat energy from solar radiation. These collectors are composed of parabolically shaped reflective sections connected into a long channel. A pipe that carries water/media is placed in the centre of this channel so that sunlight collected by the reflective material is focused onto the pipe, heating the contents. These are very high-powered collectors and are thus generally used to generate steam for Solar thermal power plants and are used in industrial applications. These channels can be extremely effective in generating heat from the Sun, particularly those that can pivot, tracking the Sun in the sky to ensure maximum sunlight collection.