26 Sep 2011
Solar Furnaces: a majestic use of solar power
Solar power can be used in many extraordinary ways. One of the most majestic applications of solar thermal energy is the solar furnace. These are enormous installations that make use of solar thermal energy for extreme high heat processes (temperatures as high as 3500oC/6330oF). The technology is wonderful for high temperature researchers; the heat produced is very clean with no pollutants. There are a variety of uses for this energy, such as hydrogen fuel production, foundry applications and high temperature materials testing. Thus science can advance without enormous energy bills. Research can take place in areas previously deemed too costly or polluting to be worthwhile. Solar power is to thank.
The largest solar furnace currently in existence is at Odeillo in the Pyrenees-Orientales in France; it has been operational since 1970. This area boasts extremely high air quality and approximately 300 days of sunlight a year, making it a perfect spot for a solar furnace. This is also the same area in which the first solar furnace was built; this solar furnace was put in place at Mont-Louis in 1949 by Professor Felix Trombe. Odeillo and Mont-Louis are within 15km of each other.
The furnace makes use of a large parabolic reflector concentrating the sun into an area the size of the common cooking pot. The reflector is discrete; 63 individual flat mirrors track the sun in unison and redirect the solar thermal energy towards the crucible.
Another application of similar technology is the SolarBeam parabolic concentrator from Solartron Energy Systems. It uses a single dish, tracking the sun on two axes, to focus the solar thermal energy onto an absorber approximately 10”x10”. The device is significantly smaller than industrial solar furnaces, but operates on the same concept. By focusing, and thereby multiplying, solar power, one may yield great efficiencies in solar thermal energy. Due to its size, the SolarBeam operates at lower temperatures than the industrial furnace at Odeillo.
The solar thermal energy harvested by the SolarBeam concentrator can be used for hot water, space heating, air conditioning or even process heat within many different types of industry. People with variety of goals can take advantage of the solar power available each and every day. This solar thermal energy is cheaper than using grid sources, all the while shielded from changes in prices or disruptions in service. Even during a cloudy day, the SolarBeam tracks the sun with its mathematical algorithms and concentrates the energy diffused through the clouds. Other systems simply cannot offer the same ability.
The sun is the source of nearly all energy on earth. Whether your intent is to melt metal or simply heat your pool with a solar hot water system, there are ways to harness solar power. It is the most efficient thing to do.