Possible Future Energy Sources"Possible Future Energy Sources." Alternative Energy. Ed. K. Lerner, Brenda Lerner, and KathleenEdgar. 2nd ed. Vol. 3. Detroit: U*X*L, 2012. 443-482. Global Issues In Context. Web. 7 Oct. 2012.Document URLhttp://find.galegroup.com/gic/infomark.do?&source=gale&eisbn=978-1-4144-9081-6&idigest=2923b1ce451be8757e1bd6892fd8aae6&prodId=GIC&userGroupName=kungalv&tabID=&docId=CX4020100023&type=retrieve&contentSet=EBKS&version=1.0Full Text:COPYRIGHT 2012 Gale, Cengage Learning10: Possible Future Energy SourcesIntroductionThe word “energy” fills the pages of this book, and many forms of energy are described in previouschapters. Energy is, however, really a very tricky and difficult term to define exactly, even forstudents who have studied physics and engineering for many years.Although it is very useful to think of energy as something that can flow like a river from one thingto another, or be stored in a battery, energy really isnt a “thing” at all. Energy does not exist by thegallon or liter, but a gallon or liter of gasoline has a certain amount of energy, an ability to flowthrough the process of combustion inside a properly designed engine, to turn gears and wheels thatmove a car.Scientists and engineers usually describe or define energy as an objects ability to do work, to movethings, make things hotter, and so forth. For example, the sun does not transfer a substance calledenergy to Earth. The nuclear reactions in the sun produce light that travels through space and thatincrease the energy level of objects the light strikes on Earth. For example, the light strikes objectsand the lights own energy or ability to do work then changes molecules in the object that allowthem to undergo chemical reactions or make them move and thereby cause the objects temperatureto rise. As students advance in their studies, their understanding of energy will change.When thinking about the possible sources of energy to be used in the future, however, it isimportant to keep in mind that because energy is not a thing itself, but rather something thateverything has, one can look for potential sources of usable energy. The world will eventually runout of substances such as oil that can be found and used at a reasonable cost, but Earth will neverrun out of energy. The challenge for future generations is the ability to harness and use new sourcesof energy to do work.Is Alternative Energy Enough?Overuse of fossil fuels such as coal, natural gas, and petroleum as a source of energy can causepollution, mining damage, and contribute to climate change. Such fuels are increasingly limitedresources because they are valuable, and they can even become a cause of war. Regardless ofattempts to make cars, machines, and devices that use fossil fuels more efficiently, fossil fuels willsomeday be very scarce and hard to find. The world needs other energy sources that are clean,renewable, and affordable.Most sources of “alternative” energy—which usually means energy from any source other thanfossil fuels and nuclear fission—depend on obvious, natural sources of energy. The sun bathes Earth
with light, which can either be turned into electricity or used directly for light or heat. The wind andrivers are loaded with kinetic energy (the energy of matter in motion). Tides raise and lower the sea,and they hold a potentially usable source of energy.There is nothing new about these energy sources. People have always used the sun to light spaces,dry food and clothing, and heat buildings. Water wheels and windmills have done useful work forcenturies. Thechallenge for modern scientists and engineers, however, is to find effective ways of harnessing thesepower sources (and others) on a scale large enough with a cost low enough to meet the needs of thepeople already living on Earth, a number that is expected to increase steadily. The world populationsurpassed 7 billion in 2011. According to a report released by the United Nations (UN), the worldspopulation will reach 9 billion by 2050 and 10 billion by 2100. Nearly all the population increase—some 97 percent—is expected to occur in developing countries.Many alternative or renewable energy sources—especially hydroelectric power, wind, and solarpower—are already providing important amounts of energy for many nations. These energy sourceshave many advantages over fossil fuels, but they also have limitations. One problem with somealternative sources is that to provide truly large amounts of energy, they require huge, expensivefacilities. Hydroelectric power needs massive dams that drown land, displace towns and villages,and threaten wildlife habitats (the living environment). Tidal or wave power needs dams across tidalbasins and machines for gathering wave energy, all of which would not only be expensive but mightspoil wild shorelines and disturb sea life.Solar cells to turn sunlight into electricity are getting steadily less expensive, but a solar power plantbig enough to make as much energy as a coal or nuclear plant would cover a large area of land.Today, large windmills can make electricity at about the same cost as coal-burning plants or nuclearpower plants, yet wind farms consist of large numbers of towering windmills—often twice theheight of the Statue of Liberty—that change landscapes and can kill birds with their whirlingblades. In addition, people often need more electricity than can be produced or stored while the sunis shining or when the wind is blowing.Nuclear power In 2010, nuclear power plants supplied around 14 percent of the worlds electricity(down from the 16 percent that nuclear power had supplied in 2005). Nuclear power plants producesteady-flowing energy, but not all experts agree that building many new nuclear power plants wouldbe an affordable way to meet the worlds energy needs. Quite apart from possible problems likeradioactive waste, potential terrorist attacks on reactors, or reactor accidents, nuclear power hasalways been—and, according to some experts, still is—more expensive than other energy sources.Contrary to popular belief, for example, orders for nuclear plants practically stopped in the UnitedStates before the near-disaster at the Three Mile Island nuclear power plant in Pennsylvania in 1979.Nuclear plants were simply too expensive. Since 1973, orders for new nuclear power plants in theUnited States have consistently been cancelled. As of 2011, the last non-military nuclear reactor tostart operations in the United States was located at the Watts Bar nuclear power plant in Tennesseein the late 1990s.The 1979 Three Mile Island and 1986 Chernobyl disasters only added to the publics apprehensionabout nuclear power. However, growing concern throughout the 1990s and early 2000s aboutclimate change—attributed to the ever-increasing use of fossil fuels such as coal, oil, and naturalgas—as well as the concerns of many governments about their countries dependence on foreignsupplies of those fossil fuels, rekindled an interest in using more nuclear power. In 2011, forinstance, 15 nations were in the process of constructing more than 60 new commercial reactors.(However, only two of those new reactors were being built in the United States: the Watts Bar 2reactor located in Tennessee, scheduled to begin commercial operations in 2013; and the BellefonteUnit 1 reactor in Alabama, projected to start commercial operations sometime between 2018 and
2020.)By the start of the 2010s, concerns about climate change and energy independence were buildingmomentum for more nuclear power stations. Then on March 11, 2011, a major earthquake struck offthe coast of Japan, producing a massive tsunami. As of August 2011, the tsunami alone wasestimated to have killed over 15,000 people, with another approximately 4,600 missing. Thetsunami also swamped the Fukushima 1 nuclear power plant complex on Japans eastern coast,which had three of its six reactors operational when the earthquake occurred. Within a matter ofdays, the three originally operational reactors were in full meltdown, and fire had swept through afourth (previously-idle) reactor. Radiation spewed from some of the crippled reactors, promptingthe evacuation of many tens of thousands of people who were living within 12.5 miles (20kilometers) of the Fukushima 1 plant.Besides the incalculable cost in human suffering wrought by the March 2011 earthquake, tsunami,and nuclear disaster in Japan, there were also, of course, huge economic costs. The financial costsof the Fukushima nuclear disaster alone were enormous. Estimates publicized in June 2011concerning costs stemming from the nuclear catastrophe ranged from a low of $71 billion to a highof $250 billion. Such costs included covering such things as compensating the evacuees for lostwages and property. Also, the Japanese government decided to permanently close Fukushima 1, andits considerable power output of around 4.7 gigawatts (4,700 megawatts) was permanently lost toJapans power grid.Intensive efforts were made throughout 2011 to bring the crippled nuclear reactors at Fukushimaunder control. In May 2011, workers were finally able to enter a building housing a disabled reactor.Previously, only robots had been able to enter the buildings of damaged reactors due to theextremely high radiation levels. Near the end of September 2011, the temperatures of the three mostheavily damaged reactors fell below 212°F (100°C) for the first time. News reporters were allowedto make their first visit to the heavily damaged Fukushima complex on November 12, 2011.Despite positive developments, major problems still plagued the recovery effort. In November2011, for instance, instruments at Fukushima detected radioactive xenon leaking from one of thedamaged reactors, indicating that nuclear fission was still occurring within the reactor, althoughprobably at a low level. A survey of radioactive contamination issued in November 2011 indicatedthat 10 percent of Japan was contaminated with low levels of radioactive cesium (Cs). Theradioactive contamination consists of the isotopes 134Cs and 137Cs, with halflives of approximately2 and 30 years, respectively. This means it will take about 30 years for half of the radioactive 137Csto disintegrate.Some nations have reacted negatively to the Japanese disaster. The German government, forinstance, declared in May 2011 that all its nuclear power plants would be permanently closed by2022. This decision was largely the result of German public opinion against the continued use ofnuclear power. Also in May 2011, the Japanese prime minister announced that his country wouldnot build any new nuclear power plants. Although some countries, such as India, continued theiraggressive plans to install more nuclear power even after the Fukushima disaster, public oppositionto those plans was sometimes fierce.The Fukushima disaster also negatively affected U.S. public opinion about nuclear power. In March2010, polling conducted by the Gallup organization showed that 62 percent of Americans favoredusing nuclear power to produce electricity. A year later, in the aftermath of the Fukushima disaster,more Americans (47 percent) opposed the construction of new nuclear power plants than favored it(44 percent). Regardless, the United States announced the approval of two new nuclear reactors in2012—the first approval in 30 years.Other Sources of Alternative Energy But nuclear power is not the only energy source withproblems. Large, centralized renewable-energy projects must be placed in specific geographiclocations and may damage the environment. A hydroelectric dam needs to be built on a river, for
example, and many rivers have already been dammed in some way. A wave-power or tide-powergenerating station would have to be built on a specific type of ocean shoreline. Windmills needstrong, reliable winds, which are not found everywhere. Solar power does best with steadysunshine, as in deserts and the tropics. Only in certain places is geothermal heat close enough toEarths surface to be useful. And there is really not one electrical energy problem but two: theproblem of generating electricity and the problem of transporting electrical power.For all practical purposes, the energy of the wind, sun, oceans, and atoms is inexhaustible.However, peoples ability to capture such energy is limited by geography, money, safety, and otherconsiderations. In fact, experts argue that these sources of power will never be able to safely,cleanly, and affordably supply the world with all the energy it needs. Furthermore, all the sources ofenergy mentioned so far in this chapter are sources of electricity, but not all energy needs can bemet by electricity. For example, electric cars and trucks that can compete with the power and rangeof fossil-fuel-powered vehicles do not yet exist. Electricity, whether it comes from windmills ornuclear power, cannot yet help people break their addiction to the liquid fossil fuel known as “oil”(petroleum), from which gasoline and other fuels are made.However, defenders of new energy sources have at least possible answers to many problems andobjections. Just as advocates of nuclear power argue that with new reactor designs, nuclear powercan be made safer and cheaper, supporters of windmills and solar power argue that new designs willeliminate limitations of these technologies. For example, large windmills might coexist withranching on the wide-open landscapes of the American Midwest or be located far out to sea, whilesmaller, more efficient, vertical-axis windmills (which resemble upside-down eggbeaters and do notharm as many birds as other designs) can be placed on rooftops.Solar panels can also be placed on rooftops, producing power where it is needed without using moreland. And by using electricity from windmills or solar panels to break water (H2O) into hydrogenand oxygen and then using the hydrogen in fuel cells (a type of chemical battery) to makeelectricity, people can get power from the wind and sun even when the wind is not blowing or thesun is not shining. Hydrogen can also power cars and trucks using traditional internal combustionengines (meaning fuel is burned inside the engines combustion chamber). In addition, biofuelsmade from plants and algae may also help fuel vehicles.Can renewable energy sources make all the energy that modern civilization needs? Many expertscontend that by using energy more efficiently, people can reduce their energy demands to the pointwhere they can rely on what renewables can provide without giving up any of the advantages of ahigh-technology lifestyle. Some experts also argue that nuclear power will, in fact, be necessary.This remains a controversial subject, especially in light of the 1986 Chernobyl and 2011 Fukushimanuclear disasters. (Both nuclear disasters greatly affected the environment, especially the people andanimals that lived nearby.)But apart from increasing efficiency—which has already reduced energy use for many tasks andcould reduce energy usage much more—no perfect alternative solutions are yet available. Claims ofgreater safety and lower cost for new nuclear power-plant designs are still just promises. Vertical-axis windmills have not yet been widely installed or tested. By the early 2010s, the closest thing toan alternative-energy “revolution” was the progress being made in wind and solar power.Wind power makes headway Of all the various types of major renewable energy sources used inthe United States—biomass (such as ethanol for fuel), geothermal, and wind, water, and solar power—the one source that has shown the greatest gain as a percentage of all renewable energy is windpower. From 2006 through 2010, the share of renewable energy produced by wind in the UnitedStates rose from 4 percent to 11 percent. Biomass had a small increase—a rise from 49 percent to53 percent of all renewable energy—while geothermal and solar remained at about the same level(3 and 1 percent, respectively). Because of low water levels in many states, hydroelectricityproduction in the United States dropped dramatically, from 43 to 31 percent of the renewable
energy mix.The rapid advance of wind power was due to several factors, including support from federal andstate governments, as well as efficiency improvements in the conversion of wind energy toelectricity in large wind turbines. The American Wind Energy Association reported that there werecommercial wind facilities in 38 U.S. states by the close of 2010, which together represented acombined capacity of 40,181 megawatts of electrical power. In 2010, U.S. wind power producedaround 95 billion kilowatt-hours of electrical energy, accounting for 2.3 percent of all electricalenergy (both renewable and non-renewable) produced in that year.Most of the growth in wind energy capacity in the United States has come in large wind “farms”that possess dozens or even hundreds of largewind turbines. For instance, the Roscoe Wind Farm in Texas, which became fully operational in2009, has a rated capacity of 781.5 megawatts of electrical power. In 2010, the top three U.S. statesin terms of wind power capacity were Texas at 10,089 megawatts, Iowa with 3,675 megawatts, andCalifornia with 3,253 megawatts. Texas, with its large area and excellent wind resources, wasespecially aggressive in installing new wind power capacity. However, a relatively small state suchas Iowa has demonstrated—by surpassing Californias formerly unbeatable wind power capacity—that the right incentives from a state government can greatly aid in the transition to renewable formsof energy.The promise of solar energy: As cheap as fossil fuels? Despite the failure of solar power togenerate more than about 1 percent of U.S. renewable energy by the start of the 2010s, electricityfrom solar power nevertheless grew by an average of 12 percent each year from 2006 through 2010.The growth in wind and biomass energy kept solars share at more-or-less the same level, eventhough in absolute terms solar energy grew significantly in the latter years of the first decade of the2000s and early 2010s.The greatest reason for optimism regarding a sustained and dramatic rise in solar energy use in theUnited States (and indeed worldwide) is the continuing fall in the cost of photovoltaic cells (alsocalled PV cells or solar cells). Throughout the early 2000s and into the 2010s, the price of solarcells continued a dramatic decline. Improvements in commercial PV cell efficiency (meaning thatmore sunlight could be converted into electricity), coupled with the economies of scale formanufacturers as more PV capacity was installed, led to a steady decline in solar cell prices. By2011, the cost to install solar power on a home or small business was between $4 and $5 per watt.The SunShot Initiative funded by the U.S. Department of Energy aims to accelerate the trend ofdecreasing PV cell cost. Created in early2011, the SunShot Initiative seeks to reach an installed PV cell price of $1 per watt. Analysts figurethat when solar power from PV cells achieves the long-anticipated $1-per-watt level, that solarelectrical power will then basically be on-par with electricity purchased from a utility. Consumersand businesses would no longer need government subsidies to justify the purchase of solar powersystems for their homes or office buildings. A homeowner or small business owner would still haveto pay the upfront costs of a solar power system, which could amount to several thousand dollars ormore, depending upon the size of the system. However, after a length of time (based on the size ofthe system installed), the solar PV system will have paid for itself in decreased utility bills. Areasonable pay-back timeframe might be between 10 and 12 years.The use of solar cells to power homes and offices is a form of decentralized power generation. Thatis, much of the power used by a homeowner or small business could be generated onsite instead ofat a centralized power station. Homes and offices will still be hooked up to the power grid for thosetimes when electrical power is needed from the utility, but oftentimes the home or office buildingwould generate all the power needed via its installed solar cells.In contrast to distributed solar power generation, large photovoltaic and solar thermal power plants
and “farms” were already in place or were being constructed by the early 2010s. For instance, in2011 the largest solar power plant facility in the world was the Solar Energy Generating Systems(SEGS) facility located in Southern California. The SEGS facility consists of nine individual farmsof solar power plants using almost a million individual Paragraphbolic mirrors, or “solar troughs,”which gather and concentrate sunlight to heat water to a high temperature. The water then turns tosteam and spins turbines to create electricity. At peak performance, the SEGS facility produces 354megawatts of electrical power that is then fed into Southern Californias power grid.The largest solar cell (photovoltaic) power plant in the world (as of late 2011) was the SarniaPhotovoltaic Power Plant in Ontario, Canada. The facility has a rated capacity of 97 megawatts.There are also other large (80 megawatt-range) solar cell power plants in Germany and Italy.It remains to be seen how much of the worlds energy can be supplied by renewable sources. In2011, Iceland obtained practically all of its electrical power from renewable sources—around 75percent from hydropower, and the remainder from geothermal. Iceland, however, is a special case.Most countries are much more limited in hydropower, either because they have severe constraintson their water supply, such as the countries of North Africa, or because further hydroelectricdevelopment raises environmental and humanitarian concerns. The Three Gorges Dam in China, forinstance, displaced around 1.4 million people from its reservoir area by the time it was completed in2008. Icelands geothermal resources are another renewable energy source that few other countriesshare, at least with the technology available by the early 2010s.Large-scale use of biomass, such as ethanol from grain and sugarcane, also raises majorenvironmental and land-use issues. Grain that is used to produce ethanol or biodiesel is obviouslynot available to feed people or animals, a situation that can translate into higher food prices. Also,plantations for sugarcane (to produce ethanol) or palm trees (to produce biodiesel) are mostlyconcentrated in tropical regions. In some countries, this has led to deforestation on a massive scale.Advances in harvesting microorganisms such as algae hold great promise for the future of biofuels.However, as of the early 2010s, progress in this area had not yet reached the stage where large-scalecommercial production of such biofuels was feasible.Deriving power from tides and ocean currents was moving forward by the beginning of the 2010s,but few commercial-sized power plants using either energy source were operational by 2011.Energy derived from temperature gradients in the worlds oceans—referred to as Ocean ThermalEnergy Conversion (OTEC)—was still very much in the research phase in 2011.WEB SITESNational Geographic Society. “Future Power: Where Will the World Get Its Next Energy Fix?”http://environment.nationalgeographic.com/environment/global-warming/powering-the-future.html(accessed November 8, 2011).National Geographic Society. “Powering the Future.”http://science.nationalgeographic.com/science/space/universe/after-oil-energy.html (accessedNovember 8, 2011).U.S. Environmental Protection Agency (EPA). “Research: Future Science.”http://www.epa.gov/ebtpages/resefuturescience.html (accessed November 8, 2011).