|Thermal Solar Power|
|Thermal Solar Power | The Tower of Power | Energy Feeding Grounds | Getting the Sun's Signal|
Solar power takes many forms. But one of the most promising forms of solar
power is the thermal solar power plant. Unlike solar cells that use chemicals
to transfer the sun's
energy into usable electricity, thermal solar power, concentrates the sun's
tremendous heat energy into heat conductors that transfer the energy to conventional
Power towers are the only form of solar power that can produce electricity during times of low solar activity, or during the night. This is possible only because these set-ups are usually hybrids with natural gas facilities. However, the solar side of the plant is still revolutionary and worthy of recognition. A field of mirrors (called heliostats), focus the sun's energy onto a receiver. The receiver centrally located within the heliostat field. This receiver is usually a tower filled with a heat-transfer medium such as synthetic oil or molten salt. The medium heats up in the tower and is transferred down a pipe to the base of the tower, where it is kept in a hot tank. From there, it is transferred to a steam generator which creates the steam required for the turbine. The cooled medium is then returned to the system and the process starts all over again.
Solar troughs are more rudimentary and least efficient. But they are very economic, and are thus, the most abundant form of solar power generation. The reflective troughs' parabolic shape creates a magnification effect that multiplies the sun's energy by 30-60 percent. The troughs' focal points have a pipe running through them that contain a heat transfer medium (usually synthetic oil). The medium in the pipes can reach temperatures of 735° F (390° C). This heated liquid is then ransferred to steam producers that turn steam turbines to create electricity.
One of the most innovative forms of solar power, the solar dish takes the same shape as a radio satellite dish. The sun's rays are reflected onto a receiver that acts exactly like the tower in the power tower configuration, but on a smaller scale. These dishes are great for individual household use, or portable power stations. A grid of solar dishes may also act as a Power Tower might, but has the decentralization and parabolic benefits of a trough system. This configuration collects the sun's energy most efficiently, and achieves a power conversion ratio of 30%. This ratio is higher than any other form of solar power.