Solar Energ: Our Hope.
We all on earth are facing an energy crisis. Actually we need energy in every walk of life. We need energy to grow food, to desalinize and purify water, to dispose off wastes, to solve medical problems, for medicine, to clean our environment, for transport of goods and our selves etc, etc.
There are many ways and resources available to meet our energy needs. Out of them the least expensive and easily available is solar energy. In fact some times this solar energy is available more than we can take. Ever gone out with intense sunlight shining on your head? One wonders why we burn fuel when this much heat and light is falling all over us. So much that we have to counter by consuming more energy powering air conditioners, coolers, and freezers.
Solar energy harnessing produces less pollution than other energy means and in the long run carbon dioxide emission is nearly zero. It is a renewable energy source which means there is an unlimited amount of energy supply available.
So we need to exploit this energy, and there are ways to do it. We can capture solar energy both on earth and in space and then convert it into a useful form i.e electricity. If it is done in space where perpetual unfiltered light is always present, then it can be transmitted to earth via micro waves. Experiments have already been performed transmitting electricity over long distances in the form of micro or radio waves. Whereas on earth we are already transmitting electricity from power production companies to grids to homes.
Converting sunlight into electricity is done by utilizing either solar thermal or photo energy. Photo energy is converted with photo voltaic cells where as thermal energy concentrates light on boilers which then run turbines.
Both methods have been used on a small scale in some countries. Now it is becoming necessary that more and more countries work on it and on a large scale. Some areas of the world like many deserts can generate enough electricity that may be exported to power the whole planet.
There are two hurdles in the way. One: our technology, which is still primitive; and conversion of sunlight into electricity is not efficient...much of energy gets wasted. Two: our will, we as humans are not spending resources and efforts in this field for research and installation.