SOLAR THERMAL POWER

Solar Thermal power is heat energy obtained by exposing a collecting device to the rays of the sun. A solar thermal system makes use of the warmth absorbed by the collector to heat water or another working fluid, or to make steam. Hot water is used in homes or commercial buildings and for industrial processes. Steam is used for process heat or for operating a turbine generator to produce electricity or industrial power.
There are several basic kinds of solar thermal power systems including “flat plate” solar water heaters; concentrating collectors, such as central tower receivers; and parabolic trough and dish collectors.

FLAT PLATE SOLAR WATER HEATERS

Water flows through tubes that are attached to a black metal absorber plate. The plate is enclosed in an insulated box with a transparent window to let in sunlight. The heated water is transferred to a tank where it is available for home, commercial or institutional use.

CENTRAL TOWER RECEIVERS

In order to produce steam and electricity with solar thermal energy, central receivers have a field of tracking mirrors called heliostats to focus sunlight onto a single receiver mounted on a tower. Water or other heat transfer fluid in the tower is heated and used directly or converted into steam for electricity.

PARABOLIC DISHES OR TROUGHS

curved panels which follow the direction of the sun’s rays and focus the sunlight onto receivers. A liquid inside the pipes at the receivers’ focal point absorbs the thermal energy. The thermal energy received can be converted to electricity at each unit or transported to a central point for conversion to electricity.

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