| solar energy technologies
Solar Heating
Solar
collectors can be installed for water-heating at residential areas, hotels, country
clubs etc. The two most common types of solar heating devices here are the
flat-plate collectors and evacuated-tube
collectors.
Flat-Plate
Collectors
A typical flat-plate
collector is an insulated metal box with a glass or plastic cover (called the
glazing) and a dark-colored absorber plate. Conventional flat-plate collectors
heat fluid as it flows through tubes in or adjacent to the absorber plate.
The simplest systems use potable household water, which is heated as it
passes directly through the collector and then flows to the house.
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| | Flat-Panel
Array |
Evacuated-Tube Collectors
Evacuated-tube
collectors are typically more efficient than flat-plate collectors due to elimination
of conduction and convection heat loss through the use of vacuum. In an evacuated-tube
collector, sunlight enters through the outer glass tube and strikes the absorber,
where the energy is converted to heat. The absorber has fin-tube design
to increase surface area.
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| | Evacuated-Tube
Array | | 
