energia para la tierra
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1990 SCIENTIFIC AMERICAN, INC
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SCIENTIFICAERC Spm Vm m
Energ for Planet Earthur ability to meet the world's ener needs
ithout destroying the planet on which we live is examinedzn this special issue. With the right incentives, much can be done
A early as 400,000 BC re waskndled in the caves of PekingMan. Revered as a deity and the
basis of many myths, re has been anessential element in the technologieson which civilized societies are founded. Engies driven by fossil fuels havereplaced human and animal muscle,precipitating the rise of industrializedsocieties. Today cities, industrial facilities and transportation networks coudnot function thout regular supplies
of energyAs long as the number of human be
ings remained small and energy needswere lited to cooking and heating,energy could be exploited thout serious disruption to the atmosphere,hydrosphere and geosphere. Now amplied by a grong population, energy use has become a potentially destructive force, locally because essions contaminate air, water and soiland globally because there is the possibility that energy use may enhance
the greenhouse eect We face a dilemma properly used, energy tecnologiesserve as instruments for realizing material well-being across the planet, butcontinuation of current trends could
SUN s the soce fom whch almostall enegy on the eath s deed. It sthe dng foce behnd photosynthess wch conets the sn's aant enegy to chemcal enegy mang plantand ltmately all anmal lfe possble. Photosynthess s also esponsblefo the fomaton of foss fels. Moedectly the sn podes enegy thatcan b capted the fom of solapowe hydopowe and wnd powe.
G R Dv
lead to a degraded environment, yielding a mean and uncertain existence
Coming to grips with the challengeof ensuring an adequate, safe energysupply is a theme that pervades thisspecial issue of Environmental concerns are not new, butour uderstanding of the planet haschanged by irtue of our newfoundability to measure ever smaller concentrations of substances and to assesstheir implicationsfor human beings
and for the earth as a whoe. And wehave come to realize that populationgrowth and its rising demands maytransform the planet in ways comparable to the eects of longterm geologic forces.
I n order to understand the magde of the challenge, it helps tounderstand where energy comesfrom and the purpose that it servesin our lives. Almost all available energy can be traced either to the sun (fos
sil fuels, biomass, wind and incoming radiation) or to the processes ofcosmic evolution preceding the originof the solar system (nuclear power)Smaller, less signicant amounts arederived from lunar motion (tidal power) and from the earths core (geotherma power).
f society could exploit only a smalportion of the solar radiation thatstrikes the earth's surface every year,
wch is equivalent to 178,000 terawatt-years (or about 15,000 times theworlds present energy supply), our en
erg problems would be soved. Of thatamount, however, 30 percent is relected back to space and 50 percent is absorbed, converted to heat and reradiat-
ed The 20 percent that remais powers the hydrologic cycle. Only a verysmall share (.06 percent) of solar radiation powers photosnthesis, from wichall life and fossil fuels are ultimatelyderived. Currently renewables (including hydropower and biomass) accountfor 8 percent of the world's energyneeds and nuclear power 4 percent; theremainder is met by fossil fuels.
ew people care about the source ofour energy supply except when it is
disrupted, but virtually all of us careabout energy services, wich rangefrom the basic needs demanded by human beings everywherecoong, heating and lightingto the hallmarks ofmodern societymotors, appliances,
wideranging mobility and various industrial processes Because the worldcannot function without relar supplies of energy, a signicant section ofthe global economy is devoted to proding these serces when and whererequired
Lighting a room, for instance, is notachieved merely by licng a switch; itis the last step in a long chain of con
G ED R. DAVIS is head of energy ingroup plang for She ll InternationalPetroleum Company ited in LondonHe has a bachelor's degree in miningengineerig from London University andmasters degrees in economics from theLondon School of Economcs and in engineering and economics from StanfordUniversity For the past decade he hasundertaken many environmental analy
ses for Shell and in particular has examined the ways in whch global energy industries might adapt to a sustainable world
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Y EVEEEEY EEY 1 ! .&l - OIL REFINERY AND MT
CUE I DISRIBUION SYS GLE AUOOBILE
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DISANERALED
ILLUINAION
ENERGY is transformed tough a chain of events. Primaryenergy ests in a crde form, say, a fossil el, that s extracted from a sedmentary repository After undergog transfor-
mation, it becomes delivered energy, whc is made avaableto the consumer, who then converts t into usefu forms andthen nally into energy services, which are the desired end
version events Energy resources-forexample, the unrened oil and natralgas recovered rom wells driven deepinto the earth's crust and the coal thatis sandwched between terrestria sediments-must rst be extracted The
primary energy (crude oil, say) is thentransported to a renery to be processed into a wide range of products,and from there fuel oi is sipped to apower plant to be burned (and thusconverted from checa to thermalenergy) The heat produced uringcombustion powers a turbine, wch inturn drives n electric generator (converting thermal to mechacal to electric energy) Eventuay the electricity
traves through wres until it reachesthe enduse appliance-the incandescent lamp-where it is transformedinto radiant energy
he uneven distribution of heworld's fossil fuels (oi, natural gas
and coal) necessitates a ourishngworldwde trade in energy coodities: some 44 percent of oil, 14 percent of gas and 11 percent of coal consumed are traded internationaly Extensive distribution systems exist toservice ts trade and ensure that resources reach the consumer Naturagas is transported over land toughsome one llion kilometers of trunkpipeles an oi trough 400,000 kilo
meters of pipes, excluding local distribution systems. About 2,600 tankersply the world's oceans carrying crdeoil; another 65 vessels deliver iquidnatura gas around the world
As a result of such global demand,
fossi fues are being depete at arate that is 100,000 times aster thanthey are being formed Coal's share ofthe world energy supply has alreadypeaked; in 1920 it accounted for morethan 70 percent of fuel use, but todayit meets oy 26 percent of global energy needs Oil peaked in the early1970's at slighty more than 40 percent(toay it is 38 percent) The portioncurrenty allotted to natural gas (19
175,-150az
125&(0 100a6t
75a 50(z 25
RIMARY ELERIIY NAURAL ASD OlL OALD OHE (INLUDES RADIIONAL FUELS)
SEAMENINE
AUUMUBE
ASOLINE WENINE 'i . .OMMERIAL
AIAION \ELEISION
NULEARENERY
IROCI
o L_________________L______L__180 1870 1880 1890 1900 1910
RATE OF PRIMAY ENERGY USE and the relative contributions of dierent sources relect the evolution of technologyas well as the growth of the human population. he rapid riseof o after World War II for example, is indcatve of the riseof mass transportation and industry Simlarly, the growth ofelectricity in the late 1960's parallels the rise of a services-ori-
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1920 190 1940 1950 190 1970 1980
ented economy. Although fossil fuels still dominate the primary energy supply, coals share peaked around 1920, whenit provided more than 70 percent of al the fuel consumed;oils share peaked in the eary 1970s at slightly more than40 percent. Natural gas, which is less pollutg than ether oor coal, is expected to contribute more to global energy use
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percent) s expected to rse further Although the remang amount of recoverable fossl fuel s thought to equalsome 10 trllon barrels of olenoughto last another 170 years at presentconsumpton ratesthe supply wleventually rn out and n the nter ( f t s fully combusted) the prospect presents a possble teat to theenvronment
How do we reconcle our burgeonng demand for energy wth the needto mantan a vable global ecosystem?There s no soluton as yet The uncertantes surroundng envroentalproblems such as clmate change andthe dversty of vews on the relatvetradeos between econoc growthand the envronment can lead to a multplcty of poles and projectons forenergy supply and use
To smplfy matters I would leto explore two possble routes to the
future The "consensus vew held bymany rests on a contnuaton of present trends whereas the "sustanableworld vew presumes that globa enroental ssues wlbe on the nternatonal agenda by the d1990's Underlyng both scenaros s the assumpton that by 2010 world populaton wltotal seven bllon and gross worldproduct wlhave doubled
In the consensus vew consumerhabts and ways of lfe are not expected to change Sgcantly and theprce of crde ol
wlprobably rse
gradually although ts trajectory maybe volatle World energy consumptons expected to ncrease by 50 or 60 percent by 2010 and the global offuels s to reman substantally thesame as today Thus global carbon doxde (C) emssons would also ncrease by 50 or 60 percent Implctn the consensus vew s that "more ofthe same s sustanable and that clmate change s ether not a serous ssue or t s somethng to wch humanscan adapt
There s much uncertanty surroundng the ssue of global warmng but fstdes do conrm a ln between COemssons and clmate change then theconsensus vew of development couldcome at great cost For example a report recently ssued by the Intergovernmental Panel on Clmate Change concludes that "busness as usual developments could lead to a global meantemperatre ncrease durng the nextcentry of about 3 degree Celsus eachdecade wth sgncant mpact on nat
ural and human systems Experence
tells us that publc polcy must be notonly adaptve but also antcpatoryThs s the bass of the sustanableworld vew
Yet the system that enables socety to produce energy does not lendtself readly to a lexble quc response An ntractable nfrastrcture(power plants may last from 20 to 40
year) long lead tmes (from blueprntto operaton for many energy projectsmay span a dozen or more years) andentrenched publc perceptons (of costsenvronmental acceptablty and need)
all mae for a system laden wth nerta Projects currently der way wchorgnated years ago wldonate thescene for years to come tll there sreason to t change s possble
Hstory tself s dened by rapd technologcal evoluton. Whereas the planet was home to oy a few hundredlon human bengs at the start ofthe ndustral revoluton t now shel
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ters some ve blon people who occupy around a bllon dwellngs drve500 llon motor vecles and expend much eort to prouce a varety of ndustral products to furtherther wellbeng Total delvered energy (the amount that reaches the end
user-the electrcty say needed tolght a lamp or the naral gas neededto heat a home) rose from the equva
lent of about eght lon barrels of oa day n 1860 to 123 llon barrels day n 1985. If rewood s excluefrom the calculaton delvered energy(mostly coal ol natral gas and electrcty) has ncreased nealy 60foldAnd energy servces have ncreased ata much more rapd pace than delveredenergy largely as a result of mprovements n enduse ecences
_ COMMERCA ELSD RADIIONAL ELS
0 10 20 0 40 50ANNAL DELERED ENERGY PER CAPIA
(BARRELS O OL EQIALEN)
GREAT DISPARITIES est in per capita energy use. The S. and Canada have hehighest rates: the average ciizen in those countries used the equivaent of 40barrels of oil 1988. In contrast the average Nigerian used oy two barrels, mostlyin the form of traditional es. The reatively high rates in he . S. S. R. and EastGermany relect the ineciency with which energy there is distributed and used
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K INETIC
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SO IATION striing te eart eac year is equal to 178,000 terawatts, orabout 15,000 times te world's present energy supply. Of tis, 30 percent is iediately relected back to space; anoter 50 percent is absorbed, converted to eatand reradiated. Te remaining 20 percent creates ind, powers te water cycleand drives potosyntesis. Some energy, in te form of geotermal eat, can betapped from te eart's core; a ty amont (generated by te moon's gravitational
pull) ests as tidal power Altoug not sown, estimates for te potential of commercial renewable resources (primarily ydropower, biomass, solar power, windpower and geotermal power) suggest tey may eventually increase from today'slevel of about one terawatt-year a year to 10 or peraps 15 terawattyears a year.Te increase in renewables depend on teir cost and environmental penalties
The demand for energy wlbe compounded further by the econoc transition envisaged for the developing nations, where 90 percent of the world'spopulation growth will take place. Inthe poorest econoes the average erson consumes an amount of traditional
fuel (such as wood and other orgacwastes, most of which are gatheredrather than bought) equivalent to oneor to barrels of oil a year. As countries industrialize and urbanize, commercial fuels displace traditional ones.The average person in a developingcountry anually uses the equivalentof one or two barrels of oil of coercial fuel (which is purchased on theopen market). n contrast, the number
jumps to between 10 and 30 barrels inEurope and Japan and more than 40 in
the US.Although reliant on traditional els,ow-income economes have gh energy intensity (energy used per unitof income) because they basically need
whatever energy form is availablenorally rewood, agricultral residuesor dung th which to cook and heatthei homesdespite the ineciencyth which such els are burned. Andso a pattern emerges: as countries become increasingly industrialized, theamount of comercial fuel used per
uit of incoe increases, but overall
energy intensity declines. Since commercial energy consumption may icrease as fast as income over long periods, the growth in energy demand in
develoing countries could be as ighas 4 to 5 percent er annum.
Solving energy problems, today as inthe past, depends on the tecologiesthat are avaiable and the rate at whichthey evolve. Sce the iddle of the19th centy, sources of power have
shifted from wind, water and wood tocoal and more recently to oil and natural gas. The interplay of ener andtecnology, as exemplied by threehases of the industrial revolution, accounts for the sift. During the rstphase, wch emerged in the early18th century, the donant technologies were coal ng, the smeltig andcasting of ron, and steamdriven railand marine transort. The syste'scoponents intertwined closely thesteam engine, develoed originally by
Thomas Newcomen for drainage andhoistng in nes, was later adapted byJames Watt to provde power for transport and the blast for iron smelters.The smelters, in trn, provded aterials for constrcting the steam engine,locomotives, rais, ships and ningequipment. Trough the creation of atransportation infrastructure and themachines to run factories, raid industrialization was possible.
Toward the end of the 19th centurythe world was again transformedthistime by electric power, inteal-com
bustion engnes, automobes, arlanesand the cheical and metallurgical industries. Petroleu emerged as a fueland a feedstock for the petrochecals
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industry. Now, toward the end of the20th century, society has embarked ona tird hase of the industrial revolution, characterzed by a sft to computers, advanced materials, otical electronics and biotecology.
The pact the third phase wlhaveon global patterns of energy consumption is not yet certain, for aplicationof tecnology depends on what society
considers its objectives to be and especially on whether the publc will em
brace more of a sustainable-world ewor not.
Coing to a global consensus willnot be easy. Energy policies vary considerably from one country to another.Whereas some goverents tax, otherssubsidize delivered energy. For some,energy is a source of revenue; for others, it is an oportty to rovide relief for the poor. Additional issues thatmust be faced include the security of
suply and the impact of energy ricechanges on lation and on a country'sbalance of trade.
Taxes levied on oil producers, for examle, are a mainstay of revenue forthe large o exporters, such as Venezuela and Saudi rabia. ong countriesin the Orgazation for Econoic Cooperation and Development EC itis mainly the consumers of energy whoare taxed. Such ocies are harly xed;indeed, some have undergone radicalshifts in a rather short time n energyimporting countries, concern over se
curity of supply, largely absent untilthe rst oil crisis of 1973, doinatedthe rest of the 1970's and early 1980'sLater in the 1980's, as surluses appeared, concern shfted to the otherside of the market: ol-exportng countries began seeking secure outlets fortheir oil.
n many countries the energy sectoris the province of stateowned copanies; in others, such as the U.K., econoc olicy has emphasized the virtes of eciency d competition, thus
encouraging privatization. Most goverments control the iact on the envronment of all asects of the enerychainfrom production to waste disposal to the disantling and decomssining of a plant The commonthread n cases is that a governmentstrives as a matter of olicy to provdeits people wth an adequate, safe, economic and equitable suly
Implementaton of such polcies wl
be profoundly inuenced by theevolution of technology, whether
applied to the deign, operation orcontrol of energy systems. Estiating the rate at which new tecologies penetrate the market is problemat-
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ic howeve because in most casesthe intediscilinay natue of tecological inteactions canot easiy bediscened in advance Fo examle unfoeseen synegies beween new mateials engeeing teciques micoelectonic devices and combustion technologies have aleady geatly inceasedthe otential eciency with wich automobes consume fuel [see "negyfo Moto Vehicles by Deboah L Ble
viss and Pete Walze age 02 butthe inceases ae ossible
The geat otential fo saving enegy though ecient technology is exloed in many aticles i tis secialissue of nold PFickett Clak W Gegs and Amoy B.Lovins suggest that eciency measueshave the otential to educe electicityconsumtion in the U S by 30 to 5ecent n the aticle "cient Use oflecticity on age 64 Rick Bevington
and Athu H Rosenfeld eview vaious stategies fo educing fuel use in
buildings in "negy fo Buildings and
EFIE:4
EEGUE:
1
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26
PI: 27
Homes on age 6 Simila savingscan be achieved n the industial secto
whch cuently accounts fo 40 ecent of the enegy used in the develoed wold [see "negy fo Industy
by Mac H Ross and Dael Steinmeye age 88
New gy ecient tecologies include comact uoescent lams andothe lighting devices which can educe the amount of electicity equiedfo lights by 90 ecent Also available ae aliances that consume onlyfom 0 to 20 ecent of the electicitythat conventional ones do A new geneation of automated contols makesit ossible to otimize lighting heating ventilating and ai-conditioningsystems In industy both adjustableseed dives and high-eciency motos omise signcant savings as doadvances in integatedocess deigncontol tecnology and ecycg In the
tansotation secto vecles caableof 60 miles e gallon of fuel o moeand vecles that on comessed
AL: AUAL A:
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natual gas hydogen and electicityae gaing attention
Develoments in eloation and oduction of ol and gas wl also be imotant The use of tee-ensionalseismic tecniques and hoizontal ling fo examle wl incease the accessibility of these esouces yet notaise thei cost igcantly Raid technological advances in the ateative-enegy secto descibed by Cal] Wein
beg and Robet H Wiliams in "negyfom the Sun on age 46 oen unew ossibilities aboatoy ecienciesof sola hotovoltaic cells have oughly doubled since the 970s and aeexected to imove futhe vaiableseed wind tubines ae cost-competitive in some makets and new pocesses fo making liquid el fom biomasssuggest viable altenatives to etole
um although on a smalle scale WolfHfele foesees that the teat of glob
al waming wl ceate a signicant dmand fo nuclea owe one that can
be met by inheently safe divesion-
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WO ENERGY LOWS for 1985 sow tat fossil els areigly versatile Crude oil y must be processed in reneries, were it is converted to gasoline, diesel and aviaon el for transportation Bot oil and natural gas d arewidely used by industry and by residential and commercial
consumers, but oy a small percentage of eac generateselectricity Most of te world's coal iht bu powers industry or generates electricity_ Hydropower, nuclear powerand oter energy sources (biomass, solar energy and ndpower) m up 22 percent of today's p energy supply
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roof reactors managed under the aegs of an nternational authority in "En
rgy from Nuclear Power, on age 136Technology s also medating a shift
away from large, centralized owerlants to smaller, decentralized ones.mrovements in electronc counations, contro and comuting tech
nology have made it easer to motorand regulate comlex grids remotely
With the arrival of new gas turbines,mall enges, solar cells and otherechnologies, the economies of scale,o long a featre of electricity generaion, are dminishing. Not only can de
centralzation be more eient, but asmulya K. N Reddy and Jos Goldemberg make clear in "Energy for the Develoing World, on age it mayoer some of the oorer countries abasis for econoic growth
In the long rn, such technologicaladvances aear likely to lower theoverall costs associated wth litnghe carbon diode emissions from fos
sil fuels In general, resonse tmesrom concet through rototye to
commercial roductare declining, aattern that is likely to contine. Jaanese manufacturers, for examle, aniciate that by 1993 cars will be de
signed and develoed in half the timeand at a quarter of the cost of today'smodels. Ther aroach highlights the
ole of global cometition as a motorof technoloical change. Snce siilaradvances are exected in other areas of
manufactring, we could be surrisedat the seed of the resonse to newincentives.
Technology, however, will roel society toward sustainabiliy most quickly if olicyakers can agree on arorate global gideines. If there is to
be any sigcant change in the structure of energy suly and use in thenext 20 years, new oliies wlhave to
be in lace by the mid1990's, whichmeans that EC members would haveto agree by then on a rotocol to osetthe ossibility of global cate change.
Broadly, the main otions are to eliminate chloroluorocarbons (which delete stratosheric ozone and contribute to global warng), initiate aorestation rograms to enlarge the carbonsink and reduce CO eissions fromfossl fuels These goals can be accomlished by iroving the eciency withwhich fossil fuels are transformed andconsumed and by shifting to alternative fuels, esecially from carbonrichto hydrogenrich els Technologies toremove carbon dioxide from coal arebeng develoed, although methods forsequestering the CO have yet to be resolved see "Energy from Fossil Fuels,
by William Fulkerson, Roddie R. Judkins and Manoj K Sanghvi, age 128
lthough each country wlundoubtedly dier, certain oliies can be exected to gain wide suort. ongthem is the "olluter ays rincile,
which calls for the user to ay the full
cost of resource use and for the marketo act as arbiter of suly and demandIt must also be remembered that COemssions er caita are 10 ies higher in the EC countries than in de
veloing countries an equitable agreement on aroriate reductions istherefore necessary.
Involving the develoing countries,as well as Eastern Euroe, the Soviet
Union and China, in the global energyresonse will be critical For many ofhese countries, economic reform is anecessary starting oint. As William UChandler, Alexei A Makarov and ZhouDadi oint out in "Energy for the Soviet Union, Eastern Euroe and China,on age 120, the ongoing globalizationof business oers hoe for the raiddiffusion of technology from one artof the world o another.
The scoe of an eective rogramhas yet to be deterined A recentstudy, reared for the 1989 Ministerial Conference on Atmosheric Pollution and Climate Change in Noord
wijk , the Netherlands, estimates caitacosts of about .8 ercent of gross domestic roduct (GDP) for a reventionrogram targeting a full haseout ofchloroluorocarbons, exanded forestmanagement and energy conservation.f fully imlemented, such a rogramcould reduce execed greenhousegaseissions in EC countries by 30 ercent by 2005 But a fcoitment tosustainablity could demand more A
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UNLE-WL VIEW
1
TWO SCENOS for the global energy m in 2010 areshown The consensus view assumes a "busness asusua atttude, with an overal growth in consumption Tesustanable-world view assumes radcal mprovements in ef
ciency with demand stabizing after 2000 In the consensusview, coal and ol expand rapy, whereas in the sustainableworld ew, coal contracts and there is a surge in natural gas.Hydropower and commercial renewable fels woud ncrease
by 60 percent. Carbon diode emissons increase unti 2000 ht but their output then depend on poicies cosen n the 1990's If energy use increases as fast aseconomic growh, CO essions
double by 2010 Wit
greater energy eciency, emissions in the consensus scenaro increase at a rate tat is half as fast. In contrast, in tesustainable view, CO emissons peak after 2000, athougthey are still 15 percent higher in 20 10 tan they are today.
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Throughout India in 99, the traditionl
"lamp of welcome wil be lighting India's
gatewy to the 90s and welcoming new
decade of tourism The 12month celebra-1 Y .tion wil be taking plce all across India
in festivals ablaze with color, pageantr ritual and custom.
With oneofkind cultural fairs and events, msic, dnce
and sumptuous native cuisines See India in all its slendor and fee te special spirit of wecome that brns
brighty in every home and every heart within India.
Se India this yer
! I inerested in pnnin isit t Indi.Plese send e he Visit India Year Kit
Name
ddress
ity ae Zip
Mi : Gene Indi s Oe/ De Bet NY
r cal: In New Yok () n Los Angeles ()
Ind .'1-',"'.
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250
200IZ> 50w
6l.o 100o
50o
o
1970
INDUSIALZEDCOUNES
1980 1990
---------SS. AND
EASEN EUOE
2000 2010PRMARY ENERGY DEMAND is expected to vary from one part of the word toanother. Most of the increase probaby occur in the developing word, wherepopuation growth rates are high and industrialization and urbanization are under way. n contrast, demand is expeced to remain stable or drop in the industriaized counries, where population growth rates are low. t coud stabiize ordecline in Eastern Europe and the U.S. S. R. depending on he success of economic reforms. Much inges on whether consensus or sustainabe poicies are enacted.
propriate enviroental expendituresmay need to be increased on the orderof 1 or 2 percent of GDP.
Sifts of that magnitde can be carried out over one or two decades withlittle econoc disruption. Silareven argersifts have already occurred. Between 1965 and 1985, for example, the amount spent by U.S. consumers on food declined by 6 percent,whereas health care expenditures increased from 6 to 11 percent duringthe same period. At the same time, energy expenditures in the EC countries dropped from 12 percent of GDPi 1980 to oly 8 percent in 1988. Today funding for the enviroment ispoorly documented, but it probably av
erages 2 or 3 percent of GDP for mostEC countries. Increasing the amountto 4 or 5 percent is certainly feasible(particularly if the defense budgets ofmany countries decline as expected
In a world that embraces sustainabiity and establishes appropriate incentives to trigger change, one could expect the following outcome in the energy sector. Assuming that populationand econoic growth are the same asin the consensus view and that international protocos are in place by theid1990's, the word's primar energysuppy could be stabilized at the equivalent of around 205 milion barrels ofoil a day by 2000. Ts by itself would
be a heroic feat. Yet even with sucha program, CO essions from fossilfuels woud be 25 percent igher in2000 than they are today. Despite a sigcant shift from coal to natural gas(combined with an increase in renewable fuel supplies and greater eciency, CO emissions would stil be higher in 2010 than they are today.
In a sustainable word, the balance ofnew itiatives would sift from producer to consumer, from energy supply to energy services and from quantity to quality of energy. importantpolicy step could be to adopt a numberof options that would integrate neededenergy services into regional and cityplaning. As Beviss and Walzer point
out, new zoning laws can deter commuting by car, and new trac guidancesystems ight reduce urban air pollution. Bevgton and Rosenfeld ghlightthe vaue of planting shade trees andpainting buildings in light, relectivecolors to reduce energy use in urbanareas. Changes to the existing transportation infrastructure, such as theproposed introduction of maglev trainsin Europe, open up options for retiking our road, rail and air networks
The corporate response to a sustainable word coud include a new breedof energy company, driven by the desire to provide a broad range of leangenergy technologies to its customers.
62 CETFC EC
Such companies could have de-ranging activities. In some urban areas, forexampe, there may be a market for privately operated mass-transit systems.In others, baning the internalcombustion engine might create facilities forparking and recharging the batteries ofelectric cars. As utilities grow more ser
vice oriented, it is quite possibe theywil expand to perform such services.The need to move quickly shoud alsoencourage research and deveopmentalliances between fuel companies andmanufacturers of combustion equipment. Such collaborations can producefuels, engines and processes that are asyet unanticipated A modest start hasalready been made in the U.S, wheresome petroleum compaies are producing reformuated gasoline and alternative els.
For many, the transition to a sustainabe world is rife with uncer
tainty and dilemmas. This is perhaps natural since we seem to be living between two stories, as expressed
by the consensus and the sustainableworld views. For others, the situation ismore clear-cut. As stated so clearly in"Managing Planet Earth, the Septem
ber, 1989, singe-topic issue of - for them, the story ofthe sustainable world is the story ofour time, a time when human beingsneed to rearm their roe as stewardssee "Energy in Transition, by ohn P.Holdren, page 156.
As we earn more about the relationhuman beings have to their planet, wemay nd that rather than viewing energy as a comodity to be exploited planet Earth, we wl increainglyneed to thi and act in terms of energy fplanet Earth. Our dependence onenergy wlpersist, but it must do so inthe context of an ecologically soundplanet. This means human beings may
well have to apply al their inventiveness to develop new energy technologies so as to guarantee the long-term
quaity of their habitat.
FURTHER REING
xR MINR ON NRG TCHNOOGIS FOR CING MISSIONS OFRNHOS SS. Collected PapersOrganisation for Economic Cooperation and Development and InternationalEnergy Agency, Paris, April,
NRG FOR TOMORRO. Collected Pa-pers Fourteenth Congress of the WorldEnergy Conference, Montreal, September ,
TCHNOOG NvRONMN. Editedby Jesse Ausube and Hedy E Sladovich. National Academy Press,
1990 SCIENTIFIC AMERICAN, INC
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7/27/2019 Energia Para La Tierra
10/10
We now import more than40 percent of a the oi we use, andthat percentage continues to groThis excessive dependence onforeign oi could poison America'seconomy and our national secuityif our supply were ever disrupted
But the moe we use nuclearenerg instead of imported oi, togenerate our electricit the ess wehave to depend on uncertain for-
eign oil suppies
Te KI Of DH?
America's 112nuclear eecticplants already have cut foreign oildependence by 4 biion barressince the oi embarg o of 1973,saving us $115 bilion in foreignoil payments
But 112 nuclear plants wilnot be enough to meet our rapidygrowing demand for electricit Weneed more plants
Impoting so much oi is a dan-
ge America must avoid We need to
rey moe on energy sources we cancount on like nuclear energ
For a free booklet on nucearenerg y, write to the U.S. Councilfor En erg yAwareness,PO. Box66080,Dept. SK10,Washington,DC. 20035
Nuclear energ means more energ independence.