capstone paper

Brad Marko
Ms. Mudd
English 151
23 November 2010
The Future of Solar Energy
The world is dependent on electricity and as long as there are people on Earth we will need electricity. However there are multiple problems that coincide with how we generate our electricity. Some of these problems include that power grid formations can only stretch so far; approximately one-third of the world does not receive electricity. Also, only so many resources are available to produce it and it is inevitable that these resources, such as coal, will eventually run out, probably sooner than later. There is one resource that is abundant, can be used anywhere and literally will not run out as long humans remain on Earth. This renewable resource is the Sun. Solar energy is the only abundant enough resource that can save the world from its fossil fuel dependency. This will only be possible with technological advances and if the United Sates government will invest in going green.

The Sun is the most plentiful resource available to produce energy and rid us of our fossil fuel dependency. It is so plentiful because it is a renewable resource that will not run out as long as the sun is shining. Currently the world’s main source of power is fossil fuels such as coal, natural gas and petroleum which are large emitters of greenhouse gases, such as carbon dioxide that are quickly filling our atmosphere. Increases in carbon dioxide levels lead to temperature increases and world catastrophe such as global warming. Since around the beginning of coal fired electricity EcoWorld has shown the precedent effects in which, “Earth has warmed by approximately .8 degrees Celsius over the last century.” Something needs to be done to reverse this trend, which is not going to stop on its own. If we stay fossil fuel dependent through the next half century our carbon dioxide levels are only going to worsen due to increase of population and increase in energy use. As Robert Samuelson of The Washington Post exclaims, “With modest growth, energy use and greenhouse emissions more than double by 2050.” Obviously we need to reverse this trend of rising greenhouse emissions. The only way to keep these gas levels constant would be by making energy more efficient or we will have to invest in a different energy source than coal (Samuelson). Zweibel, the author of The Terawatt Challenge for Thin Film Photovoltaics explains that solar energy is probably the only alternative due to the size of the resource (427).

Solar energy is harnessed two main ways. By solar water heating and the use of thin film photovoltaic solar cells. Atul Sharma and C.R. Chen enlighten that solar water heating specifically has been used for over sixty years. However, thin film photovoltaic solar cells are what will save the world. The solar panels consist of photovoltaic solar cells that are usually made of cadmium telluride or silicon. Mary Cooper of Renewable Energy explains the photovoltaic systems are, “usually arrayed in modules of several cells . . . made more powerful by incorporating lenses or mirrors to concentrate the sunlight.” The sunlight is what generates the power. The question that critics of solar energy ask is, “can thin film PV meet the Terawatt challenge?” (Zweibel 427). The answer to this question is yes indeed, it can. The terawatt challenge is the estimated usage of electricity by the year 2050, which is a whopping thirty terawatts total worldwide (Zweibel 428). A terawatt is equal to one trillion watts and currently the world uses about ten terawatts and the United States is accountable for three of them. It is predicted that if we want to just stabilize, not reverse, carbon emissions that, “the world will need about 20TW of non CO2 energy to stabilize CO2 in the atmosphere by mid century” (Zweibel 428). This is obviously a big task at hand and it has been found out that other renewable resources such as biomass, wind and hydroelectric simply do not amount up to enough potential energy to meet the challenge. On the other hand sun rays emit approximately 125,000 TW which is more than enough potential energy to help power the world (Zweibel 428). It is apparent that long term transmission of solar energy is harder than it sounds and will not be attainable over night. Photovoltaic solar cells have a fairly steep price and are still under-developed as far as efficiency goes. The future of solar energy looks promising though with always advancing photovoltaic technology and as Mary Cooper elucidated, market demand is also increasing: “Sales of photovoltaic cells and modules have grown by some 10 percent over the past decade.” Scientists such as Nader Barsoum and Pandian Vasant have proposed ideas by which solar energy technology can improve for future use and efficiency.

Solar energy can only make advances in worldwide usage if technology develops to increase efficiency and lower costs. The current problem Nader Barsoum and Pandian Vasant of Simplified Solar Tracking Prototype is that a lot of solar panels are in fixed positioning which limits the potential of photovoltaic solar panel output. The idea proposed by Nader Barsoum and Pandian Vasant is that in order for solar panels to maximize efficiency they need to constantly be angled at a perpendicular angle of incidence to the sun’s rays. By maintaining a perpendicular angle of incidence this will increase total potential energy output in thin film photovolataic solar panels. Single axis freedom for solar panel movement increases efficiency by approximately twenty percent but double axis freedom of movement for solar panels is believed to be able to increase efficiency by forty percent (Barsoum and Vasant). The double axis freedom of solar panels would help maintain the sought after perpendicular angle of incidence for the sun’s rays.
In order to obtain the double axis movement of solar panels there is a system that must be created. Requirements for the solar panel to move about in such fashion are shared by Barsoum and Vasant in which, “two separate but identical circuits will be utilized for both axes.” The challenge in this theory is the creation of the two circuits that will but used for the solar tracking technology. In the creation of a circuit there will be two light dependent resistors made with cadmium sulfide. Light dependent resistors are more or less photocells that are sensitive to illumination from the sun. These two light dependent resistors will be connected to a PIC microcontroller which with the development of certain software will be able to read and react to the illumination of the two photocells (Barsoum and Vasant). As illumination readings from the sun, this is measured in lux, increases and decreases the resistance of the light dependent resistors acts inversely. When the resistances of the two light dependent resistors differ the PIC microcontroller will in turn activate the motor to angle the solar panel in the direction to where the resistances of the photocells are in equilibrium (Barsoum and Vasant). By doing so this will ensure that maximum input from the sun is achieved to therefore maximize efficiency of the photovoltaic solar panels. Maximizing efficiency will make solar panels more worthwhile for consumers hence making the product more popular on the market.

Solar energy will likely only be able to experience market growth under one condition: if the United States government will endorse the use of it. The primary consumer of energy in the United States is the government themselves. We learn this in The Big Green Buy by Christian Parenti when he explains. “The federal government is the world’s largest consumer of energy and vehicles, and the nation’s largest greenhouse gas emitter.” Through logic I deduct that if the government will endorse in clean energy that the rest will come. The main problem with solar energy is that it is simply too expensive for the average household to invest in. Price is the major hold back because when it comes to solar energy, “it is too expensive, while fossil fuels are far too cheap” (Parenti). The only way as of now that solar energy prices would be able to compete with coal prices is if coal plants perfected and began using sequestration which would most likely raise costs of electricity fifty to one-hundred and fifty percent (Zweibel 429). Sequestration is the process of capturing carbon dioxide while it is burning and storing it in underground aquifers (Zweibel 429). Only in the event which sequestration was practiced could the high cost of renewable resources compete with the price of fossil fuels.

Instead of making all energy expensive I find it easier to just make solar energy costs go down. The government is responsible for thirty-eight percent of the country’s GDP or gross domestic product. It is projected for the government to spend 3.6 trillion dollars just this year. This means that the government spends so much money that if they would re-route to the usage of solar energy that it would assist the growth of a green economy by lowering costs (Parenti). This type of cost reduction would open up clean energy to the private sector because it would be more affordable. This theory of government supplementation is backed up by examples such as the microprocessor that is quoted by Parenti in the article:
Gates explained to the Washington Post that much of what is touted as free-market economy was born of government subsidies: ‘The internet and the microprocessor, which were very fundamental to Microsoft being able to take the magic of software and having the PC explode, were among many of the elements that came through government research and development.’”
The government has the spending capabilities to drive down costs. The amount of buildings for solar panel installation is plentiful as well considering the United States government “owns or leases more than 430,000 buildings (mostly large office buildings)” (Parenti). Thankfully President Obama is trying to make progress towards going green and being cleaner when he signed Executive Order 13514. Executive Order 13514, “directs all federal agencies to ‘increase energy efficiency; measure, report, and reduce their greenhouse gas emissions. . . design, construct, maintain, and operate high performance sustainable buildings in sustainable locations’” (Parenti). Green products, which solar energy is included in that category, will also be obligatory to be purchased through the government according to the executive order: “The executive order also stipulates that federal agencies immediately start purchasing 95 percent through green certified programs and achieve a 28 percent greenhouse gas reduction by 2020” (Parenti). These numbers may look promising but if we want to rid ourselves of our carbon dioxide saturated atmosphere then we will need greater collaboration from the government. Alan Zarembo anticipates stabilizing the carbon dioxide level in the atmosphere would require a seventy to eighty percent drop in carbon emissions. Without fully fledged government support solar energy will take much longer to evolve.

I describe solar energy as a win-win situation. With the enhancement and use of solar energy we can power the whole world while lowering carbon dioxide emissions. There would be clean air and we will not have the worry of running out of the sun as a resource as we do with coal. Solar energy still needs to make advancements in technology in order to optimize efficiency which would also spur greater usage of solar panels. The double axis of freedom concept is a great way of making solar panels more efficient. Even after technological breakthrough we still have to rely on the government to get with the program and buy the idea. This would provoke lower costs for the usage of solar energy making it more affordable to all.
 
Works Cited
Barsoum, Nader, and Pandian Vasant. "SIMPLIFIED SOLAR TRACKING PROTOTYPE." Global Journal of Technology & Optimization 1.(2010): 38-45. Academic Search Complete. EBSCO. Web. 6 Oct. 2010.
Cooper, Mary H. "Renewable Energy." CQ Researcher 7.41 (1997): 961-984. CQ Researcher. Web. 5 Oct. 2010.
“Global Warming Skeptics Are Deconstructing Al Gore’s Inconvenient Truth.” Ecoworld.com. 15 Nov. 2006. 23 Oct. 2010 web.
Parenti, Christian. "The Big Green Buy." Nation 291.5/6 (2010): 15-20. Academic Search Complete. EBSCO. Web. 6 Oct. 2010.
Samuelson, Robert J. “Global Warming’s Real Inconvenient Truth.” WashingtonPostc.com. The Washington Post 5 Jul. 2006. 23 Oct. 2010 web.
Sharma, Atul, and C. R. Chen. "Solar Water Heating System with Phase Change Materials." International Review of Chemical Engineering - Rapid Communications 1.4 (2009): 297-307. Academic Search Complete. EBSCO. Web. 6 Oct. 2010.
Zarembo, Alan. “Game Over on Global Warming?” truth-out.org. Los Angeles Times 5 Feb. 2007. 23 Oct. 2010 web.
Zweibel, Ken. “The Terawatt Challenge for Thin Film Photovoltaics.” Wiley Series in Materials for Electronic and Optoelectronic Applications. Ed. Jef Poortmans and Vladimir Arkhipov. West Sussex, England: John Wiley and Sons Ltd, 2006. 427-462. Print.