The Future of Solar Energy
What is the future of solar energy? Is it a viable alternative energy resource, which when fossil fuels inevitably run out, will become a conventional energy resource?
An enormous amount of solar energy is available and because of this great availability, the future solar energy harvesting has attracted much attention. Calculations indicate that if we can harvest solar energy at 20% efficiency then 3% of the area of the USA could provide all the energy we need.
At first glance 3% does not sound like a large area. Expressing this area in other ways provides a feel for the immense scale of the collectors needed if we are to supply all our energy needs from sunlight. The contiguous 48 states have a total area of 7 710 516 km2. Three percent of this is 230,505 km2, or nearly the area of the state of Wyoming, at 252 539 km2. Of course, the sun does not shine all the time in Wyoming. The 230 000 km2 must be located where the sun shines a good portion of the time. This means the collection sites must be located in New Mexico, Arizona and southern California. It’s questionable whether or not California would be willing to donate that kind of space for the future of solar energy.
Dedicating 230 505 km2 to the production of energy might be a good investment in the future of solar energy if practical solar energy conversion techniques can be developed. However, solar energy is already in full use by the ecosystem. It drives the weather, heats the oceans and grows the plants. Moving large amounts of solar energy from the southwest and transmitting it to the rest of the country may have unpleasant environmental consequences.
The future of solar energy at this rate may cause as much damage as the combustion of fossil fuels. For instance, if a large part of the solar energy landing on Arizona is converted to electric energy and moved out of state, Arizona will become colder. Significant cooling of Arizona will result in dramatic variations in the weather there and in all the neighboring states. Insignificant growth occurs in the shade of a solar collector. A shortage of plant cover under the solar collectors will affect the stability of the soil and the absorption and movement of water. So considering the future of solar energy potentially means the destruction of the environment, it will likely to prevent large-scale collection of solar energy.
In addition to the potential for environmental harm the future of large-scale collection of solar energy may cause, grave doubts exist concerning our ability to collect the energy. Solar energy researchers have been working hard since the oil price crisis of the mid-1970s. Thus far they have not found a practical method of harvesting solar energy on an extensive basis. Apparently, small scale dispersed solar heating of homes or swimming pools is technologically possible, but lacks practical implementation. The solar energy collection equipment adequate to provide year round solar heating costs 5-10 times as