Solar + Thermal +Wind = ELECTRICTY

Have you heard about solar energy, the energy harnessed from the sun? How about Thermal energy, the energy harnessed deep within the earth? Or how about Wind Energy, the energy harnessed from the air currents? If you did, did you know these different energy sources can be combined to produce yet another energy source? It is called Solar Chimney Technology. Yes literally a chimney similar to chimneys found in household only bigger!

(Image from http://www.renewableenergymagazine.com)

According to http://www.renewableenergymagazine.com, a solar chimney power plant consists of a circular transparent collector raised a certain height from the ground, with a chimney at the collector centre. A single turbine or multiple turbines are located at or near the base of the chimney and are connected to an electric generator or generators.

So how does the Solar Chimney work?

(Image from http://en.wikipedia.org/wiki/Solar_chimney)

(Image from http://en.wikipedia.org/wiki/Solar_updraft_tower)

Radiation from the sun penetrates the collector (Solar Energy) and strikes the ground surface beneath (Thermal Energy), which is heated and in turn heats the adjacent air (Wind Energy), causing it to rise. The warm rising air is trapped underneath the collector, but rises up into the central chimney, causing the air under the collector to be channeled into the chimney as well. The air flowing into the chimney drives the turbine or turbines which subsequently generates electricity cited by http://www.renewableenergymagazine.com).

(Image from http://www.solar-chimney.biz)

So why use Solar Chimneys?

• Solar chimney power plants utilize beam and diffuse solar radiation. Therefore, although reduced, the plant still generates power under cloudy conditions.
•  The ground (soil) underneath the collector of a solar chimney power plant acts as a natural energy storage mechanism, which allows the plant to generate power at night.
• Construction materials that are used for such a plant are relatively inexpensive and readily available.
• The plant does not require any non-renewable fuels in order to operate and does not produce any emissions. This also means that the plant would never have to deal with escalating fuel costs.
• At suitable plant sites such as desert areas, solar radiation is a very reliable input energy source. Consequently, energy produced by solar chimney power plants will not produce power spikes which may occur with schemes such as wind energy generation.
• Solar chimney power plants do not require any cooling water making them ideal for use in water resource poor areas.
• Low maintenance cost.
• Improved ventilation rates on still, hot days
• Reduced reliance on wind and wind driven ventilation
•  Improved control of air flow though a building
• Greater choice of air intake
• Improved air quality and reduced noise levels in urban areas
• Increased night time ventilation rates
• Allow ventilation of narrow, small spaces with minimal exposure to external elements

(Cited by http://www.renewableenergymagazine.com and http://en.wikipedia.org/wiki/Solar_chimney)

Posted by: Dan Kevin Trinidad