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 Solar cookers and water heaters use solar energy to operate.
 Black surfaces absorb more energy than other surfaces and solar cookers use
this property by coating their insides black.
 They use reflecting surfaces like mirrors to focus the sun’s rays.
 The device is covered with a glass plate thereby establishing the greenhouse
effect by trapping heat inside the cooker.

Solar cell

 A device that converts solar energy into electricity is known as a solar cell.
 A typical solar cell produces a voltage of 0.5 1 V and 0.7 W of electrical power. A
large number of such cells can combine to form a solar panel which can generate
power large enough for practical uses.
 Advantages: (i) no moving parts (ii) require little maintenance (iii) can be set up in
remote areas without the hassle and expenses of transmission lines.
 Disadvantages: (i) Requires a special grade silicon which is not easily available
(ii) Usage of silver for interconnections makes it expensive.
 Uses: traffic signals, calculators, artificial satellites and space probes.