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1、Photovoltaic Solar Energy Futures,Presented to the Minnesota Futurists 16 May 2009 Dick Saunders and David Keenan,But first a word from our sponsor,The Futurist Tool of the day Trend Analysis and Extrapolation,Trend Analysis & Extrapolation,A Method Everyone Uses Trend analysis involves the use of a
2、ny of a variety of techniques based on historical data. Trend analysis involves several processes. One process is spotting an emerging trend, that is, identifying a change in the world around us. Now you need to do some analysis to see what the nature of the trend is and what its implications might
3、be. You could first look at historical data,http:/crab.rutgers.edu/goertzel/futuristmethods.htm,Trend Analysis & Extrapolation,Trend Analysis & Extrapolation,Trend analysis requires that you do more than simply extrapolate the trend forward. You have to ask, what is causing this trend, and will thos
4、e causes continue indefinitely? Are there upper limits to the trend? What other forces may affect the trend? At this point trend analysis relies more on subjective judgment rather than objective extrapolation of historical data. Assuming that the future will be like the past or that past changes wil
5、l continue in the same direction and rate is a perfectly sensible way to begin trying to understand the future. It can not, however, be the end of our endeavors, or we would end up with absurd results.,http:/crab.rutgers.edu/goertzel/futuristmethods.htm,Trends to Analyze in This Talk,Solar Cells Mar
6、ket size Market share Sales Units Power produced Cost per power delivered,Agenda,The Sun Solar Cells Background How they work Types Markets Costs Countries Companies Questions,Now on with the show,Energy from the Sun,About half the incoming solar energy reaches the Earths surface. The Earth receives
7、 174 petawatts (PW) (1015 watts) of incoming solar radiation at the upper atmosphere. Approximately 30% is reflected back to space while the rest is absorbed by clouds, oceans and land masses. Earths land surface, oceans and atmosphere absorb solar radiation, and this raises their temperature. Sunli
8、ght absorbed by the oceans and land masses keeps the surface at an average temperature of 14 C. By photosynthesis green plants convert solar energy into chemical energy, which produces food, wood and the biomass from which fossil fuels are derived.,http:/en.wikipedia.org/wiki/Solar_energy,Breakdown
9、of incoming solar energy,http:/en.wikipedia.org/wiki/File:Breakdown_of_the_incoming_solar_energy.svg,Energy from the Sun,Yearly Solar fluxes & Human Energy Consumption The total solar energy absorbed by Earths atmosphere, oceans and land masses is approximately 3,850,000 exajoules (EJ) (1018 joules)
10、 per year. (70% of incoming sunlight) (1 Joule = energy required to heat one gram of dry, cool air by 1 C) Primary energy use (2005) 487 EJ (0.0126%) Electricity (2005) 56.7 EJ (0.0015%) Therefore a good target 2002, more energy in one hour than the world used in the year. Photosynthesis captures ap
11、proximately 3,000 EJ per year in biomass. The amount of solar energy reaching the surface of the planet is so vast that in one year it is about twice as much as will ever be obtained from all of the Earths non-renewable resources of coal, oil, natural gas, and mined uranium combined. As intermittent
12、 resources, solar and wind raise issues.,http:/en.wikipedia.org/wiki/Solar_energy,Solar Cells Background,1839 - French physicist A. E. Becquerel first recognized the photovoltaic effect. Photo+voltaic = convert light to electricity 1883 - first solar cell built, by Charles Fritts, coated semiconduct
13、or selenium with an extremely thin layer of gold to form the junctions. 1954 - Bell Laboratories, experimenting with semiconductors, accidentally found that silicon doped with certain impurities was very sensitive to light. Daryl Chapin, Calvin Fuller and Gerald Pearson, invented the first practical
14、 device for converting sunlight into useful electrical power. Resulted in the production of the first practical solar cells with a sunlight energy conversion efficiency of around 6%. 1958 - First spacecraft to use solar panels was US satellite Vanguard 1,http:/en.wikipedia.org/wiki/Solar_cell,PV Sol
15、ar for Electricity,Photovoltaics For the 2 billion people without access to electricity, it would be cheaper to install solar panels than to extend the electrical grid. (The Fund for Renewable Energy Everywhere) Providing power for villages in developing countries is a fast-growing market for photov
16、oltaics. The United Nations estimates that more than 2 million villages worldwide are without electric power for water supply, refrigeration, lighting, and other basic needs, and the cost of extending the utility grids is prohibitive, $23,000 to $46,000 per kilometer in 1988. A one kilowatt PV system* each month: prevents 150 lbs. of coal from being mined prevents 300 lbs. of CO2 from entering the atmosphere keeps 105 gallons of water from bei