The energy from the sun is collected in two methods. The Photovoltaic method (Knier,2002), which is a semiconductor technology that converts the light energy into electricity, has been usually used. The energy from the sun can also be controlled through heat absorption. This thermal energy is then used immediately or is stored for later uses. The use of solar energy is encouraged because its use leads to a reduction in over reliance of fossil fuel to produce energy. This in turn leads to reduced energy bill costs and carbon dioxide emissions. By using solar energy, the average household reduces the amount of carbon dioxide emissions by approximately 20%. The energy costs have been increasing to the use of energy from fossil fuels. Solar energy was established as an alternative source of energy in the late 1960s and the first homes built then relied on solar panels simply and therefore required another source of energy as a back up. With time, solar energy has become well established, modified, and sophisticated to become the most obtained after form of energy source. This has controlled to the increase in the sale of solar products and solar homes. Green industries have increased as well as the solar power is clean, environment friendly, and it reduces residential and industrial carbon prints.
The photovoltaic method, utilizing semiconductor technology to convert the solar energy into electricity, has been most commonly used. However, the indirect method using concentrated solar beams to generate heat, usually referred to as Concentrated Solar Power (CSP) has been used for several larger, power generation installations (Philibert, 2010).
As solar energy does not create carbon dioxide (CO2) emissions during operation, its use leads to reduced CO2 emissions overall. When comparing the relative levels of CO2 emissions arising from different energy sources, the United Nations Environment Programme (UNEP) (2008) stated that coal produces:
twice the emissions of gas,
six times the amount of solar,
40 times the amount of wind, and
200 times the amount from hydroelectric power.
Whilst solar power as a source of energy is not as efficient in that regard as either wind power or hydroelectric power, it is more convenient than both for many energy customers. A wind turbine with the generating capacity to satisfy the power needs of a typical North American home would need to have a rotor diameter of between 14 and 20 ft. (Gipe, 2006). Clearly this is not practical for all but the largest home sites.
Similarly, whilst hydroelectric power seems a really attractive option, for the great majority the lack of a suitable water source on the property, i.e. a flowing stream or river with a sufficient flow/head combination rules out hydroelectric power rightaway. Plus, any water source would need to provide that energy year round, i.e. not dry up in the summer months.
Also, while costs of energy produced from nuclear energy and/or the traditional fossil fuels such as coal, oil, or natural gas have been increasing over the years and are continuing to rise, the costs of manufacturing and installing photovoltaic solar power systems has decreased as the technology improves and manufacturing is moved to countries offering low labour costs (Lorenz, Pinner & Seitz, 2008).
Whilst it cannot yet be claimed that – taking into account capital investment costs – solar energy is cheaper than energy sourced from traditional fossil fuels, it is heading in that direction and is assisted by certain State and government subsidies. Estimates vary, but it is likely that solar energy will be cheaper overall than fossil fuel energy in the next decade or so, even without government subsidies and/or tax breaks. For that reason, solar power is seen to have a bright future.
References
Gipe, P. (May 2006). Small Wind Turbine Size to Meet Household Consumption. Retrieved from http://www.wind-works.org/articles/SmallWindTurbineSizetoMeetHouseholdConsumption.html
Knier, G. (2002). How Do Photovoltaics Work? Science at NASA Headline News.
Retrieved from http://science.nasa.gov/science-news/science-at-nasa/2002/solarcells/
Lorenz, P., Pinner, D., & Seitz T. (07.09.08). The Economics of Solar Power. McKinsey Quarterly. Retrieved from http://www.forbes.com/2008/07/09/solar-power-economics-lead-cx_pldpts_0708mckinsey.html
Philibert, C., et al., (2010). Technology Roadmap – Concentrating Solar Power. International Energy Agency. Retrieved from http://www.iea.org/papers/2010/csp_roadmap.pdf
UNEP (June 5, 2008). Twelve Steps to Help You Kick the CO2 Habit (Step 6). United Nations Environment Programme, World Environment Day – 5 June 2008. Retrieved from
http://www.unep.org/wed/2008/english/Information_Material/factsheet.asp
