Sunbeam Power Solutions

The fixed temperature controller (FTC) method was adopted by the solar industry in india for a long period. even now some manufacturers are supplying with this design. the FTC method involves the arrangement of collectors in series-parallel or parallel-series configeration. cold water is let into the collector and it remains there without circulation until the desired temperature, say 80ºc, is reached. at the end of the bank of collectors on the delivery-load side, a thermostat and an electro-hydraulic valve are fixed. as soon as the water in the collectors reaches the set temperature, the electro-hydraulic valve opens and releases the hot water either to the process or to a storage tank. this type of system is not efficient because for efficient heat transfer, there should be a good temperature difference and an optimum flow in the collectors. the flow should be neither too slow nor too fast. in the former case the absorber loses heat because of its high temperatures and in the latter case the time is insufficient to transfer the heat from the absorber to the liquid in this method the thermal losses are high and hence it is not a desirable practice.

A heat exchanger is a device built for efficient heat transfer from one medium to another, whether the media are separated by a solid wall so that they never mix, or the media are in direct contact. They are widely used in space heating, refrigeration, air conditioning, power plants, chemical plants, petrochemical plants, petroleum refineries, and natural gas processing. One common example of a heat exchanger is the radiator in a car, in which a hot engine-cooling fluid, like coolent, transfers heat to air flowing through the radiator.

Solar Collector

Collector
Absorber Material	Copper 0.27 MM(32 Swg) copper
Absorber Coating	Black Chrome selcctive coating NALSUN      technology it is internationally acknowledged to the best. Absorptivity > 0.96 Emmisivity < 0.20
Riser	Copper tube of dia 12.5mm, thickness 0.71  mm(22 Swg) DHP Grade IS 1550 : 1967
Header	: Copper tube of dia 25mm, Thickness 0.71 mm(22 Swg) DHP Grade IS 1550 : 1967
Bonding b/w Riser & Header	Silver Brazing
Bonding b/w Fin & Tube	Ultrasonic Welding / Fusion Welding
End Connection	63 dia brass flanges (4 mm thickness)
Collector Box	100mm * 25mm Jindal Aluminium Andonized Chanell with MRF coating
Collector Bottom Sheet	Galaluminium(22Swg)
Back Insulation	50 mm  thick Resin bonded Rock wool,   Density 48 kgs / cu m, R value =1.82m2K/W
Side Insulation	25 mm thick Resin bonded glass wool,     R value =1.67m2K/W
Glazing	Toughened glass, 4 mm thickness,    Transmissivity 88.8% @ near normal incidence
Glazing Retainer	Unique proprietary Galauminium Retainer of    1.6 mm thickness
Glass Beeding, GasKet &        Gromments	EPDM