You must have read in your science classes that the Sun is the ultimate source of energy on the Earth. What if we can convert that energy into power in quantities sufficient to meet all power demands of the earth? Do you suggest using lot of solar panels? What if there is no Sun for days in a rainy season? No power. There is a solution – trap the sunlight outside the earth’s atmosphere which remains unaffected by weather.
Solar Satellite Power (SSP) is the concept which proposes a satellite placed in a high geosynchronous orbit to trap the unobstructed sunlight, convert it into electricity and then beam it back in form of microwave to earth via an antenna fixed on the satellite.
SSP is a really good concept which assures renewable power with zero emissions. It is environment friendly and very safe.
When there is lot of hue and cry about global warming and climate change, it is one alternative available for the humanity to use without emitting harmful gases which have started threatening the very existence of several species. The sea level is found to be rising slowly but fairly capable of submerging several habitats-both human and animal. There are islands in the Sunderban which have been reported submerged in the saline waters of the sea and more and more of them are threatened to meet the same fate.
The people living in these islands are not the one who use power guzzling ACs, drive cars to cinemas or shopping mall. They have contributed the least to the worsening climate change but have to bear the brunt of the wrongdoings of others most of those who live in developed nations. The US with less than 5 per cent of the world population leads the emission lists with about 24 per cent of the total carbon emissions in the world. US has the responsibility to improve the crisis faced by the environment. SSP may be one of the way to decrease the emissions and improve the world environment.
The concept was first introduced in 1968 and later the method of transmitting power to a receiving antenna on earth as microwaves from an antenna on the satellite was patented by Peter Glaser. Though the concept was not considered feasible in its initial days, it is considered as a serious option now.
The SSP concept is the simpler than any method of power generation on earth. The power units of the sun – the photons fall on the solar panels of the satellite which generate power.
Alternatively, solar dynamic method can be used where a heat engine is used to drive a piston or turbine connected to a dynamo or generator. This power is then converted into microwaves and beamed to the ground receiver antenna on the earth via another antenna on the satellite.
SSP has the advantage of being illuminated by the sunlight almost all the time except for few days in a year that too for some time during equinoxes when the sun is directly above the earth’s equator. The solar panel of the satellite being outside the earth’s atmosphere, the sunlight is intense and available without any hindrance making the energy more efficient for power generation.
Though the concept is simple, it’s not easy to be actualized. The main obstacle in achieving the SSP power is the sheer size of the satellite required for the purpose. Depending on the distance of the satellite from the earth, the wavelength of the microwave used and other laws of physics, the antenna on the satellite should be 1-1.5km in diameter for best efficiency. The elliptical ground antenna for receiving the microwave may be required to be 14km by 10km. The economic difficulty may be realized by the fact that every any object being launched into an orbit may require Rs3,00,000-Rs6,00,000 per kg.
Sources: wikipedia, Frontline, Space
