how solar energy use in thermal generation?

3 Responses to how solar energy use in thermal generation?

1. No88oN says:

   March 2, 2010 at 5:36 am

   usually solar energy is used to heat water(or any other liquid with heat transfer characteristics)

   so for example ,solar thermal power plants,they use sun to heat the water till it becomes steam under high pressure to turn on turbines which generate electricity.

   Also thermal water heaters in homes use the same idea where sometimes vacuum tubes are used where water passes through them,These tubes are designed such that they absorb the solar energy (photons with energy transformed to heat) but in the mean time they dont dissipate heat back to atmosphere
   References :
2. indian tiger தமிழன் says:

   March 2, 2010 at 6:15 am

   in solar thermalpower plants, SOLAR PANEL is used to heat the water directly and to convert it to steam..
   References :
3. Ecko says:

   March 2, 2010 at 6:56 am

   There are two approaches. One uses a heat engine like a stirling enginne or a steam engine. The other focusses the suns rays on a thermo electric generator, which has a hot and a cold junction, similar to a thermocouple or peltier module.

   The solar collector needs to track the sun, and collects the sun from a relatively large area to focus it on a small area so it can be very hot. For efficient steam engine operation the temperature could be over 500C. Some use trough shaped collectors, some parabolic reflectors.

   An example that is being produced in the US by Stirling Energy Systems uses an 11 meter diameter parabolic mirror for collection, and this uses hydrogen as the working fluid to drive a stirling engine with a 25KW generator. The efficiency is higher than a photovoltaic system, but it does not work if there are clouds over the sun, so these are best in certain regions, like deserts.
   References :
   http://www.stirlingenergy.com/