Solar turbines are just steam turbines with a very slight variation in its design. They use steam in operation. Steam required is not heated by fossils or other carbon -di- oxide and polluting gases producing fuels. Steam required in solar turbines is produced by heating water with sunlight. A number of parabolic mirrors heat a transmission fluid which in turn boils water. In order to improve efficiency of system parabolic mirrors are concentrated on boiler tubes so that more heat is absorbed. This steam is used to drive solar turbine which on being connected to a generator produces electricity.
Solar turbines are available in ranges from 50 to 150 megawatt producing electricity or as required by the indenter. Its efficiency is based upon the fuel gases that run its blade. The transmission fluids available are difficult to heat above 400 degree centigrade. Most solar plants operate at 380 degree centigrade. A cleaner source of energy, low manufacturing cost and low operating cost makes it the best solar turbine.
Apart from use of steam, natural gas can also be used to move blades of turbine to give rotary motion and thereby producing electricity with generator. Such turbines are known as solar gas turbines.
For producing electricity in remote areas where electricity is not available a combination of solar turbines with solar panel wind turbines may be coupled for continuous supply. This is the most commonly available form of green and hygienic form of energy.
Market for solar turbines is enormous in future. In present day users Spain leads all nations. Germany is also not far behind. Conversion efficiency, installation cost and operating cost is directing the economical viability of a plant. North Africa, Middle East, North Australia, South Western U.S.A. are preferred lands due to abundance of sunlight. Plant installation is not limited to any particular place. Basic challenge is to reduce acreage of Mirror Park to reduce investment cost.
Cost of solar turbines is also a phenomenon which needs immediate attention. These are built with materials suitable for higher temperatures so they are reliable, their operational cost is low and they give energy security as they are independent of petroleum fuels. A 50 megawatt plant costs 300 million pounds to build, out of which turbine cost is 15 million pounds.
Design for specific requirements is carried out by the supplying firms. Power plants to light a small village may require small power while an industry may require 200 megawatts. Both of these requirements lead to separate designs of solar turbines and so solar turbine price is an individual subject.
Solar turbine industry along with wind energy is in initial stage and a lot of experiments are in process. All over world turbine manufacturing firms of repute are innovating new ideas and implementing them to improve efficiency of system. But it is no hindrance to expansion of this green form of energy which has replaced Atomic energy in a number of countries.