Environmental Problems, Their Causes, and Sustainability 1

Typical citizens of advanced industrialized nations eachconsume as much energy in six months as typical citizens indeveloping countries consume during their entire life.MAURICE STRONGThis chapter evaluates fossil fuel and nuclear powerenergy resources. It addresses the following questions:■■■■■How should we evaluate energy alternatives?What are the advantages and disadvantages ofconventional and nonconventional oil?What are the advantages and disadvantages ofnatural gas?What are the advantages and disadvantages of coaland converting coal to gaseous and liquid fuels?What are the advantages and disadvantages ofconventional nuclear fission, breeder nuclear fission,and nuclear fusion?17-1 EVALUATING ENERGYRESOURCESWhat Types of Energy Do We Use?Supplementing Free Solar CapitalAbout 99% of the energy that heats the earth and ourhomes comes from the sun, and the remaining 1%comes mostly from burning fossil fuels.Some 99% of the energy that heats the earth and all ofour buildings comes directly from the sun at no cost tous. Without this essentially inexhaustible solar energy(solar capital), the earth’s average temperature wouldbe 240°C (400°F), and life as we know it would notexist.Solar energy comes from the nuclear fusion of hydrogenatoms that make up the sun’s mass. Thus life onearth is made possible by a gigantic nuclear fusion reactorsafely located in space about 150 million kilometers (93 millionmiles) away.This direct input of solar energy also producesseveral other indirect forms of renewable solar energy.Examples are wind, falling and flowing water (hydropower),and biomass (solar energy converted tochemical energy stored in chemical bonds of organiccompounds in trees and other plants).Commercial energy sold in the marketplace makesup the remaining 1% of the energy we use. Most commercialenergy comes from extracting and burningnonrenewable mineral resources obtained from the earth’scrust, primarily carbon-containing fossil fuels—oil,natural gas, and coal—as shown in Figure 17-2.What Types of Commercial Energy Does theWorld Depend On? The Fossil Fuel EraAbout 78% of the commercial energy used worldwidecomes from nonrenewable fossil fuels.About 84% of the commercial energy consumed in theworld comes from nonrenewable energy resources (78%from fossil fuels and 6% from nuclear power; Figure17-3, left, p. 352). The remaining 16% comes fromrenewable energy resources—biomass (10%), hydropower(5%), and a combination of geothermal, wind,and solar energy (1%).Oil drillingplatformon legsFloating oil drillingplatformGas wellImpervious rockOil and Natural GasOil storagePipelineOil wellValvesPumpCoalMined coalUndergroundcoal mineContourstrip miningArea stripminingGeothermal EnergyHot waterstorageGeothermalpower plantDrillingtowerWater is heatedand brought upas dry steam orwet steamPipelineWaterpenetratesdownthroughtherockNatural gasOilCoal seamHot rockWaterWaterMagmaFigure 17-2 Natural capital: important nonrenewable energy resources that can be removed from theearth’s crust are coal, oil, natural gas, and some forms of geothermal energy. Nonrenewable uranium oreis also extracted from the earth’s crust and then processed to increase its concentration of uranium-235,which can be used as a fuel in nuclear reactors to produce electricity.http://biology.brookscole.com/miller14351