Solar EnergySolar energy is the most ancient kind of energy found on earth, for it is as old as the sun. “Solar” means from the sun. The earth is only one of the many planets which is bathed in the sun’s overflowing energy. Every second the world receives 95.8 trillion watts of powerjust think about that for a minute. Think about how much power the earth just received in the time it took you to read this sentence? It is well beyond the amount of power used in one day. It has the potential to satisfy all our energy needs forever without ever having to use the pollutive fossil fuels ever again. “The problem however, does not lie in the limited source, as do fossil fuels, but in harnessing it.” Every day solar energy is being used all around us. In fact, it is the indirect source of all energy and life on earth. Hopefully, with continued research, we will be in a place one day where we can directly rely on the sun for all our energy needs, and never have to use pollutive fossil fuels, or nuclear power ever again (Cross 124).
It is hard to say when solar energy was first used by humans to make life easier. As far as we know, people have always used the sun’s visible range of light to see by, as well as to sit in the sun to keep warm. “Some of the first ancient cultures to use solar energy as heating were those from the deserts, and dry areas.” In Egypt, Libya, and Algeria, where the sun is fiery hot in the day, but reaches freezing temperatures at night, builders discovered that thick walls of mud could solve this problem. During the day, they would absorb all the sun’s energy and leave it cool as a cave inside, and at night, the walls would radiate their stored heat, and keep it fairly warm inside.
These ancient people also discovered how to use the sun’s energy to preserve food by either drying fruits or meats in the sun, or baking them. They found techniques to bleach cloth and cure animal hides. Whether by accident, or deliberate experimentation, these ancient cultures discovered that the sun was an incredible source of power (Bower 36).
Throughout history people have experimented with the many uses of the sun’s power. In the 17th century, scientists in Europe began rediscovering the sun. When a French scientist proved that the sun’s rays could melt copper and fuse pieces of iron if concentrated and focused through a glass prism, people began to see the usable power of the sun. In the 1690’s an Italian scientist invented a solar furnace that was so hot it could shatter a diamond, one of the hardest substances on earth (Asimov 119).
The real question around the beginning of the 19th century concerning solar energy was “could the sun produce electricity directly?” The main motivation behind this desire was that electricity could be stored in a battery, and used later. It would not be necessary to use the device in the sunlight. All inventions failed, until Frank Shuman, an engineer from Pennsylvania finally made a breakthrough. He built an experimental plant that used black troughs covered in glass with a few inches of water. When exposed to the sun, the water got very hot, causing it to circulate and power an electric generator. His data was so convincing that he got financial backers and built the world’s first solar electric power plant in Egypt. However, the Eastern Sun Power Company went out of business even though it was using free fuel. It didn’t produce enough electricity for the area that it used, 14,000 sq. ft of sun-collecting land (Zweibel 48).
In 1954 Bell Laboratories invented the first photovoltaic (or solar) cell, made from the semi-conductor silicon, and other elements. It was the first way to convert sunlight directly into electricity. When the space program was launched in the 60’s, it became obvious that solar power was the best choice for satellites, because they can be small and light, and don’t need heavy batteries or other types of generating electricity. After NASA and other major researchers backed solar energy, the technology greatly improved. “The first major use of solar cells, other than in satellite, were various emergency units and in remote areas where power lines couldn’t be reached.” In these situations, it was more expensive to run power lines than to purchase the costly solar equipment. In the high mountains of Papua New Guinea, where there is too much jungle for easy access, there are necessary telephone lines run by solar power and only visited for routine check-ups. In the US also, we have an emergency telephone back up system powered by solar panels in case of a power outage or natural disaster (Bower 29).
Solar cells today are used to power a number of things. They are popularly used in agriculture where they supply the power to pump water, prevent ice from forming on ponds where livestock drink, heating barns to keep animals from freezing, and temporary lighting. They are used to operate electric dams in areas that cannot be supplied by power lines.
Solar powered objects have started to appear quite commonly in many consumer items such as watches, radios, calculators, rechargeable batteries, flashlights, etc. The main attraction in these items is that you don’t have to replace the batteries, which saves money in the long run (Gutnik 192).
California has the largest tax write-offs for investors in solar energy. Perhaps then it is not surprising that at one time California had the most installed solar electric systems in all of the U.S. “One of the largest data collecting centers, called the Photovoltaic for Utility Scale Applications or PVUSA, is located in Davis, California.” Their focus is to collect data on maintenance and operation of large-scale solar power plants. These research facilities are important if there is to ever be a hope of having the mainstream be powered by solar energy. Before the government will invest money in solar energy, they want full proof data that there will be reliability of the systems and enough efficiency to overcome the cost (www.web.net) Solar cells are made from silicon, one of the more abundant elements on earth. When in its pure form, it forms tetrahedral crystal lattices because of its four outer shell electrons. “When thin layers are bonded with small amounts of other elements that have three or five outer shell electrons, they form a small electric field on either side of the junction.” This is because one side has too many electrons (negative charge) and the other side has too few (less electrons than protons). Within seconds of their marriage, the ones on the border hop back and forth to fill the holes. This creates a small electric field at the junction, which makes it hard for the other electrons to cross, even though they want to. But when electromagnetic waves (sunlight) hit the surface, photons (carried by light), essentially kick electrons out of place on the junction, creating “holes” which are filled by the other “loose” electrons. This builds up, creating a flow of electrons or electricity. You can wire a number of cells together to create a solar panel.
In some ways photovoltaic cells seem like the answer, and they would be, if not for a few current drawbacks. One, the kind of grade silicon needed for solar cells is very expensive. It is grown in tall cylinders, and then cut in thin wafers. However, the cutting process is wasteful and expensive. A new product is polycrystalline silicon, which is grown in thin sheets and cut in squares. This technology is being developed and has a promise. “Although polycrystalline is not as efficient as natural silicon, it’s significantly cheaper, and lowering the cost is one of the most important things in making solar energy practical.” The other problem, is storage. At this point, storage of the electricity is usually in battery form, and batteries are highly pollutive, not to mention expensive. A solar scientist recently stated that “solar energy is a field for visionary inventors and entrepreneurs. The methods and inventions of today are no more advanced now than the Model T was when the automobile was becoming popular in America.” This can give us hope, if we look at the overall picture. We have only really been looking at the possibility of solar power seriously for the past fifty years, and fossil run machines and power plants have been researched for the past century. It has been estimated that we only have 50 to 70 years left of all fossil fuels at the current consumption rate. This is a scary figure, considering that as soon as 2050 there could be no more food to feed the industrialized machine. Something will have to change, it’s obvious, and solar power is the most logical answer (Zweibel 167).
California’s recent energy crisis has sparked sudden interest in solar power by homeowners desperate to cut costs and avoid threatened blackouts. Before deregulation threw the utility industry into turmoil, solar companies were averaging about one inquiry a month about residential solar systems. Now many solar companies are averaging about twelve calls a day and twice as many e-mails. “Unlike traditional solar users looking to heat their pool, water heater or trim the monthly bill, many of those now considering sun-generated electricity want to pay the extra $3,000 for a battery bank to keep the juice flowing in a blackout.” The great thing about solar power is that once you’ve paid for the system you don’t have to worry about rising utility costs. You’re basically buying all your electricity at once. However, the cost is still a main factor to be considered. Pool heating systems start at $3,500. Arrays of rooftop solar panels capable of generating one kilowatt of electricity cost at least $7,500 even with the solar panels now costing about one-third of what they did a decade ago. Still, the average household requires two to four times that much power, meaning that it would take about a $30,000 system to save about $15 per month for each kilowatt of power generated. It would take about 20 years until enough electricity would be generated to offset the investment. Despite the great cost of solar energy systems, people are still investing in them because of their obvious benefit to the environment and because once you have it installed, the energy is free; it falls from the sky (www.web.net).
Where is the future of solar energy going? It’s a good question and many scientists have predicted all sorts of different ideas for solar energy. But regardless of what they say, there is no doubt that solar energy cannot do anything but continue to grow and slowly replace the fossil-fueled world around it. It is estimated that the sunlight that falls on the surface of the earth in the time period of two weeks is equivalent in energy to all the energy stored in all the oil and natural gas and coal and other fuels that exist on, or under the earth (Cross 136). With an energy source like solar power, that’s environmentally safe, and limitless, we would be incredibly foolish not to use it.
One idea being researched right now by Arthur D. Little Inc., was inspired by the problem of inconsistent sunlight. The sun’s rays are not constant on earth due to weather, location, and season. To avoid this scientists have envisioned “huge solar powered space stations that would orbit the earth, capable of sustaining themselves for decades.” They would generate electricity by a vast array of mirrors on solar cells, and then the energy would be converted to micro-waves that could be beamed to earth and then distributed. These stations are estimated to be about 10 miles long, and some 23,000 miles above the earth. As far fetched as this seems, it’s actually theoretically possible, and may one day be our source of power. One flaw in the plan however, is that there is actually quite a lot of space debris floating around at high velocities. If this debris collided with the solar panels, as it invariably would, they would be damaged. How much, and at what price is still to be figured (Gutnik 47).
Another idea is the “solar farm.” It would be ideally located in desert regions where it is sunny almost every day. The farms would actually harvest sunshine, using flat plate collectors to absorb immense amounts of heat, which would in turn heat water. The heated water would turn giant turbines, and produce electricity.
Sadly, the U.S. has been the slowest and most reluctant to back solar projects. Fossil fuels are too available and cheap for the investment in solar energy to be worthwhile. Ironically, although the sun’s energy is free, the curse of solar power is that the techniques are always too expensive (Asimov 46-47). Even if we don’t use one of the new solar inventions, the basic answer is simple: we need to cut back on our consumption of power. We need to stop being so lazy and dismissing solar energy as too expensive and inconvenient; the technology is there, it just needs to be cultivated. Once solar energy is more commonly used, the price will be greatly reduced. The abundance of fossil fuels is dramatically dwindling and soon there will be none left. Besides the upcoming scarcity of fossil fuels, their highly pollutive nature makes solar energy a much healthier and wiser decision. Perhaps the solution to the energy problem is that we need to be more moderate with our power usage. Do we need an unlimited supply of energy day and night? Perhaps if we cut back solar energy would be a more realistic option. Does every house need two computers, 3 TV’s, a dishwasher, microwave, electric stove, video games, 3 stereos, nightlights in every hall, porch lights left on all night, lights on in every room in the house, blow dryers, toasters, electric heaters, air conditioners, electric gates and garage openers… the list goes on and on. One of the major problems that I see in our western culture is our obsession that we must each have our own. No one is willing to share anything, because it might be inconvenient. All we can think of is ourselves, no thought for future generations or the environment. We need to get a reality check. There is not enough materials or energy left in the world for this to continue to go on. Solar energy is a serious option that we should all be considering. We need to learn to act as a community, not only as individuals. I don’t know what the future holds, but I can’t see this working much longer. Change will have to occur soon, or we will exhaust all our resources and chances of life on earth.