If you measure the sun's power in terms that compare it to the energy produced by oil, the sun gives enough energy to the Earth in about 20 minutes to fulfill all of the planet's requirements for a year! And in fact, solar energy already provides a great deal of power to the Earth by transforming through a variety of natural means, by heating surfaces, influencing weather phenomenon, and even through photosynthesis, which provides plants with the energy they require in order to grow.
So what are some ways that we on Earth can take better advantage of all this freely distributed solar power? Energy from the Sun can be processed in three primary ways:
1. Passive Solar Techniques
This refers to the ways that the sun's light and heat can be used to advantage without any further processing needed. This category includes things as simple as allowing sunlight to stream through a window and into a home, warning the rooms naturally.
Some ways to take advantage of passive solar techniques would be use of energy efficient windows, and planning the best placement of concrete and ceramic floors so that they can collect and store more sunlight.
A building that has been optimized for passive solar may have additional windows placed on the south side, for instance, to take advantage of the most hours of sun per day. Even something this simple can greatly reduce home energy bills.
2. Collection of Solar Energy
Solar power can be collected and stored as heat energy. Solar Collectors take in solar radiation and then concentrate it into very defined areas, increasing the strength and heat of the energy. These can be used to heat or cool water or rooms, or to create power to enable air or liquids to transfer heat to a separate location.
Different types of solar collectors include:
– A set of pipes that fits into a copper or metallic flat plate that has been insulated inside a box under glass. The sun streaming through the glass produces heat in the plate, which is then directed into the liquid in the pipes. This is known as a “Flat Plate Collector”.
– A tube is a more efficient way of collecting solar energy at high temperatures. This type of solar collector is made from a series of tubes, which are then installed in separate glass vacuum tubes. These prevent the inner tubes from cooling, and ensure that more heat is sent into the fluid. At extremely high temperatures, a reflector may be used in order to concentrate the solar energy into the tubes.
– Heating water using solar power was the first use of solar energy, starting in the early twentieth century. These systems can be used year round (even in cold climates when combined with use of anti-freeze), and are now commonly seen in many countries.
– Solar powered air heaters mounted to a wall are used primarily to heat the ventilation air for buildings that have large open spaces. The air comes through holes in a dark metal container where it is heated and is then taken into the building.
– A newer form of solar collector involves the use of mirrors to run steam turbines that create electricity. These thermal power systems are becoming particularly popular in hot, dry climates where there is a great deal of both sunlight and open land.
– Evacuated tube collectors can also be used to power cooling systems by taking the high temperature heat from the tubes. This technology can help reduce the use of natural gas, which would ordinarily be used to run cooling systems.
3. Solar Cells
Solar energy can be turned into electricity through use of photovoltaic (PV) solar cells. This method uses modules each consisting of an array of solar cells which are connected together inside a glass covered container. Any number of these modules can be used together in order to produce a larger or smaller amount of power, depending on what is needed for a particular application. PV solar cells are usually made from crystalline silicon or quartz. Other materials that can be used are amorphous silicon, cadmium telluride, or copper indium di-selenide.
The cost of making PV cells and solar panels (modules) has been decreasing recently with the development of new manufacturing techniques. These are widely used to provide power for remote stand-alone structures such as lighthouses and radio towers, and for heat and lighting in developing countries. The use of solar panels to supply energy for home use is increasing in developed countries as well, and many governments are encouraging their use by providing financial incentives to those who install solar panels for their residences. In addition, improvements in the process of constructing solar panels is now making it much easier for people to build their own, at a dramatic cost saving over commercial panels. It is now quite feasible for a homeowner to save a great deal on electricity by building and installing their own solar panels.