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2005 Essays - July

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* Go to Part II (August) *


    *Please note: the title of this essay has been changed slightly from what was listed earlier in order to more accurately reflect the final content. Once again it is an interactive essay. Although it can be read as is, links are embedded at various points in the article. By clicking the link you can read more about the particular topic being discussed, then return to the essay by clicking your browser's "back" arrow. (The links are included for information purposes only. No guarantees are made as to the accuracy of the materials presented on the sites, although every effort has been made to search out reliable and respected sources of information.) Footnotes and a bibliography are also included at the end for anyone wishing to learn more about the subject. The materials represented here are only a small fraction of what is available on this subject matter. The glossary link below has been provided as a reference for use as needed. If your browser does not allow you to see text in the box, click here to reach the glossary.*


     Back in 1950, driving a car 10,000 miles annually cost nine cents per mile, and gasoline sold for 27 cents a gallon. (n1) Today, with gas selling for nearly ten times that amount in some Southern California locations, drivers have to wonder, "What comes next?" While forecasts of gas priced at three dollars a gallon or more vary, one thing is for certain -- all drivers can benefit now by taking steps to obtain the best fuel economy from their current vehicles.

     But what about in the years ahead? According to some, the pings and clinks before a silent engine might not be the sounds of your car running out of gas, but of the world's petroleum resources running dry. As a result, legislation at both federal and state levels and millions of dollars of research and development funds have, over the last decade or two, been focused on two primary goals. The first is decreasing the country's dependence on foreign energy sources, and the second is protecting the environment by decreasing harmful transportation emissions and building "cleaner" vehicles.

     These "cleaner" vehicles are often referred to as "green" cars because of their less-polluting and more environmentally-friendly features and operation. Now available in an increasingly greater number from a wider variety of manufacturers, these "green" cars may be more than simply an environmentalists's dream. They quite literally may be the vehicles which drive us into a new transportation future. One of the most revolutionary aspects of this future could be a move away from conventional (petroleum) internal combustion engines, the engines that power almost all of the cars in the world today.

     For now, "green" vehicles include primarily electric, hybrid, alternative fuel and cleaner gas cars. By some projections these types of cars could represent more than 20 percent of all automobiles sold by 2025. (n2) Eventually these vehicles also could come to include fuel cell cars powered by hydrogen.

     Some may have heard California's governor promoting the development of the state's new Hydrogen Highway - a series of stations designed for the refueling of such hydrogen-powered vehicles. This is just one step toward what some envision as a country-wide shift (by the middle to the end of the century) to a hydrogen-powered economy.

     Part one of this two-part essay series will look at fuel economy, "green" cars currently available on the market, the internal combustion engine (ICE) vs. fuel cells, and give a brief introduction to the concept of a hydrogen-based economy. Part two will include a more in-depth look at fuel cells as well as a more detailed discussion of what a transition to a hydrogen-based economy might entail.


     Most experts agree that the world's supply of crude oil will run out before the end of the present century." (n3) Known reserves of high-quality oil represent about a 30-year supply at the current rate of use. (n4) These reserves are likely to be augmented by non-conventional sources such as "Canadian oil sands and Venezuelan extra-heavy bituminous crude, especially after the year 2020. (n5) However, barring any new major discoveries, global supplies of the fuel which powers a good portion of our present economy do not appear likely to last forever.

Fuel Economy

     Does this mean that the price of gas is destined to go up to $3 or $4 a gallon anytime soon? No one can say with any certainty, and even experts' opinions seem to vary. From a consumer standpoint, the most immediate steps that can be taken to get the most from gasoline dollars are to improve a current vehicle's fuel economy. The Automobile Club offers the following suggestions:

  • Make sure spark plugs are in good condition

  • Check air and fuel filters at least twice a year. Dirty filters can increase fuel consumption and can cause poor performance

  • Inflate tires according to manufacturer recommendations. Under-inflated tires can cut fuel economy by as much as 2% per pound of pressure below the recommended level

  • Have the vehicle serviced regularly by a certified technician

  • Don't use premium fuel unless your vehicle's engine requires it

  • Keep your eyes open for low fuel prices, but don't waste gas driving to a distant station to save a few cents

     These and other common-sense tips are available in an Automobile Club (AAA) pamphlet called the "Gas Watchers Guide." It is available from your local AAA club office or at http://www.aaapublicaffairs.com/. Additional information can be found at the U.S. Department of Energy/Environmental Protection Agency site http://www.fueleconomy.gov/. You can also click on the icons below to view listings of the lowest gas prices in Orange County, Los Angeles County ane other areas.

Cleaner, "Greener" Cars

     Because Americans "continue to purchase larger, less fuel-efficient vehicles, . . . the average fuel efficiency of new vehicles has changed little over the past 20 years [and remains at] about 24 miles per gallon." (n6) Although energy production is "by far the most significant source of energy-related CO2 emissions, . . . the transport sector share of energy-related emissions can range by country from as little as 12% . . . to over 45%." (n7) In the United States, "cars, SUV's and other 'light' trucks emit 16% of all carbon dioxide and other greenhouse gases released. [It is estimated that] if every American switched to a hybrid vehicle that got 40 miles to the gallon . . . it would cut these emissions by nearly half." (n8) (You can view a list of all 2005 vehicles achieving 40 miles per gallon or more in city, highway or combined driving at http://www.40mpg.org/).

     For a person purchasing a new car and wanting to take into account both fuel efficiency and emissions, there are several information resources with which to begin. The 2005 Fuel Economy Guide, an annual publication, lists MPG estimated fuel costs for all current makes and models as well as information tax incentives, advanced technology and the components of gasoline prices. The fuel economy website, http://www.fueleconomy.gov/ also features an annual coast calculator which allows a person to use local gas prices and personal driving preferences in estimating fuel costs for a particular vehicle. The Environmental Protection Agency's (EPA's) "Green Vehicle Guide" contains similar but more detailed emissions information. It includes an air pollution "score", greenouse gas "score" and fuel economy ratings in a searchable database for all makes and models. (Visit www.epa.gov/greenvehicles/index.htm.)

     As stated earlier, the number and variety of "green" cars available to the public continues to increase each year. In addition to the vehicles already available, Acura, Toyota, Chevrolet, Mazda, Nissan, Saturn, GMC, and Mitsubishi, among others, are all expected to add at least one hybrid model to their existing car lines over the next two years. (n9) Still, a person need walk no further than across the floor of any major automobile show to know the numbers of such vehicles are small compared to the total number of makes and models in existence. So exactly which types of cars are considered "green?"

     The following five categories summarize information contained in the California state government's "Drive Clean" website. For further information on the charging/fueling, safety and other features of automobiles in a particular category, click on the category name to go directly to the full information in the "Drive Clean" site.

  • Alternative Fuel Vehicles: Alternative fuel vehicles (AFVs) are those that can run on a fuel other than gasoline or petroleum-based diesel. Such fuels include biodiesel, ethanol, methanol, natural gas or propane.

  • Cleaner Gas Cars: While all California cars have advanced emission control systems, many new vehicles with cleaner versions of internal combustion engines are designed to produce extremely low levels of emissions. These vehicles are rated as PZEV's (Partial Zero Emission Vehicles) because they meet the Air Resources Board's most stringent tailpipe emission standards, among other things. The current emission rating system contains several similar acronyms which cover a range from least to most stringent emissions standards. The chart below illustrates the acronyms on a continuum. Click on the full chart to go to the Drive Clean website for definitions of each of the terms. Manufacturers like Honda place small stickers on side windows of cars falling into several of these categories; check with your local car dealership concerning a particular make or model.

  • Electric Vehicles: Electric vehicles are cars that run on electricity stored in batteries. They are the only true zero emission vehicles available today because they have no tailpipe exhaust and no evaporative emissions from fuel systems.

  • Hybrid (Electric) Vehicles (HEVs): HEVs combine an internal combustion engine with a battery and electric motor and do not need to be plugged in to be charged. The electric motor and engine work either alone or in tandem at various parts of the drive cycle to improve fuel economy and lower emissions.

  • Fuel Cell Vehicles: Though not available commercially at the present time, fuel cell vehicles harness the chemical energy of hydrogen and oxygen to generate electricity without combustion or pollution. The only emission from the hydrogen-powered vehicles is water.

     With all the positive information surrounding these "green" cars, one might also ask if there are any drawbacks to ownership. There are a few. In the case of hybrids, for example, many can cost anywhere from "two to three thousand dollars more than their conventional counterparts," (n10) and they often do not obtain their full mpg rating mileage. (n11) Service locations and technicians are limited, and with hybrids, the $2,000 - $3,000 battery pack needs replacing every 10 years. (n12) On the other hand, there are also tax credits available for many electric, hybrid, ethanol/biodiesel and other alternative fuel vehicles which are valid through at least the year 2007. For a full listing of available government financial incentives, visit the Alternative Fuels Data Center at http://www.eere.energy.gov/afdc/progs/search_state.cgi?afdc/US

     Will one or all of these vehicles emerge as the "car of the future?" No one can say yet with 100% certainty, and even manufacturers of the vehicles differ in their opinions:

"Hybrids represent the bridge to the long-term solution of clean, hydrogen fuel-cell vehicles . . . the ultimate answer, we believe, for eliminating the automobile from the environmental equation. . . For the long term out strategy can be summed up in one phrase - hydrogen fuel cells."

Rick Wagoner
GM Chairman and CEO
2005 NAIAS Press Conference
January 9, 2005. (n13)

"Hybrid's technology potential is becoming clearer by the day. At Toyota, we do not regard hybrid technology as simply a stepping stone to the age of fuel cell vehicles. We see it as the core technology that will become dominant in the eco car market and eventually evolve to form the basis of what we call the 'Ultimate Eco Car.'"

Toyota Motor Company
"A Guide to Hybrid Synergy Drive" brochure, 2003.

Still, by some estimates "the automotive industry has already invested $4.5 billion in the development of (hydrogen) fuel cells, and experts estimate that the market for fuel cells will grow from a very modest $220 million in 2000 to a staggering $95 billion by 2010." (n14) In addition, last year the Bush Administration launched "a 5-year $1.7 billion initiative to commercialize hydrogen-powered cars by 2020." (n15). But why hydrogen?

Hydrogen and Fuel Cells

     Hydrogen is the most common element in the universe. "When burned or oxidized in a fuel cell, it emits no pollution, including no greenhouse gases. Gram for gram it releases more energy than any other fuel. And as a constituent of water hydrogen is all around us." (n16) It is abundant, but unlike oil, it is not a primary fuel source. Instead, it is "like electricity, an energy carrier that must be generated using another source of power." (n17) Most of the hydrogen produced today is produced from natural gas "via a process that is about 60 percent efficient [compared with 80 percent for gasoline refining]. But since fuel cells powering electric motors are much more efficient than gasoline-powered engines, their overall efficiency is about 10 percent better -- and they also produce about 45 percent fewer greenhouse gases." (n18)

     Fuel cells are nothing like the internal combustion engines powering today's vehicles. A fuel-cell vehicle "is essentially an electric vehicle powered by a device that operates like a refuelable battery. Unlike a battery, though, a fuel cell does not store energy; it uses an electrochemical process to generate electricity and will run as long as hydrogen fuel and oxygen are fed to it." (n19) Perhaps the best way to understand the difference in operation between ICE and fuel-cell engines is to view animations of the two. Click the button below on the left to go to a GM site on the operation of internal combustion engines. Click the button below on the right to view a fuel cell animation presented by the National Fuel Cell Research Center at the University of California, Irvine.


     Although today "between 600 and 800 fuel-cell vehicles are reportedly under trial across the globe," (n20) enormous technical and commercial challenges remain for both the development of commercially viable fuel cell automobiles and the "storing, transporting and utili[zation of] renewably produced hydrogen." (n21) These challenges will be discussed at greater length in the second part of the essay series in August.

     In addition to their automotive uses, fuel cells have numerous applications in power generation, and there may eventually be a link between the two. Some people believe that "we're likely to see a fuel cell installed in a home or a subdivision long before we find one under the hood of a car." (n22) This concept of distributed power generation in which electricity is generated in small units close to users (e.g. at household, neighborhood, business, industry or commercial locations) (n23) will also be introduced next month.

     Representative of the Department of Energy consider that a transition to a hydrogen-based economy would occur in four phases, and the year 2015 has emerged as the key year in the first phase. At that time it is expected that much of the initial government and private industry research and development will be completed, enabling decisions on the commercialization of hydrogen-related technologies to take place. If the schedule proceeds as expected, the second phase, "Transition to the Marketplace," "could begin as early as 2010 for applications such as portable power, [with] . . . mass-market penetration (of hydrogen fuel-cell vehicles) occurring around 2020." (n24) The plan is not without critics, and a report published last year by the National Research Council, The Hydrogen Economy: Opportunities, Costs, Barriers and R&D Needs, concluded that "near-future prospects for a hydrogen economy are dim." (n25) Please visit the Essays page again in August to read more about these and other issues in "Green Cars and the Road Ahead: A Clear Future - Part II." See you then!

FOOTNOTES - The following are the footnotes indicated in the text in parentheses with the letter "n" and a number. If you click the asterisk at the end of the footnote, it will take you back to the paragraph where you left off.

n1 - AAA, Gas Watchers Guide, Heathrow, Florida: AAA Association Communications, Stock 2700, pp. 4-8 (*)

n2 - United States Department of Energy (DOE), Energy Information Administration (EIA), Annual Energy Outlook 2003. Washington D.C.: EIA, US DOE, January 2003, p. 62(*)

n3 - Vital, Tina. "Industry Surveys: Oil and Gas Production and Marketing: October 2004," in Standard and Poor's Industry Surveys, Vol. 3 M-A, April 2005, Vol. 172, No. 43, Section 1, p. 5(*)

n4 - United States House of Representatives, Committee on Science, Subcommittee on Energy, "President's National Energy Policy, Parts 1 & 2," Serial 107-45, 107th Congress, 1st Session, June 12 & 14, 2001, p. 153(*)

n5 - International Energy Agency (IEA), World Energy Outlook 2002. Paris: OECD/IEA, 2002, p. 101(*)

n6 - AAA, "Gas Watchers Guide," p. 2(*)

n7 - International Energy Agency (IEA), Energy Policies of IEA Countries: 2003 Review. Paris: OECD/IEA, 2003, p. 4(*)

n8 - Fairley, Peter, "Hybrid's Rising Sun," Technology Review, Vol. 107, No. 3, April 2004, p. 36(*)

n9 - Naughton, Keith, "Green and Mean," Newsweek, Vol. CXLIV, No. 21, Nov. 22, 2004, p. 52(*)

n10 - Bohr, Peter, "Driving Eco-nomics," Westways, Vol. 97, No. 1, January/February 2005, p. 48(*)

n11 - Ibid.(*)

n12 - Ibid.(*)

n13 - Online reference from GM website: www.gm.com/company/gmability/adv_tech/100_news/speeches/naias_wagoner_010905.html(*)

n14 - United States House of Representatives, Committee on Science, Subsommittee on Energy, testimony in hearing "FreedomCAR: Getting New Technology into the Marketplace," 107th Congress, 2nd session, Serial No. 107-84, June 26, 2002, p. 64(*)

n15 - Service, Robert F. "The Hydrogen Backlash," Science, Vol 305, August 13, 2004, p. 959(*)

n16 - Ibid.(*)

n17 - Ibid.(*)

n18 - Vanderwerp, Dave "Honda Proves It's Ready for a Hydrogen Economy. Now Where's the Hydrogen?" Car and Driver, Vol. 51, No. 1, July 2005, p. 77(*)

n19 - Ashley, Steven, "On the Road to Fuel Cell Cars," Scientific American, Vol. 292, No. 3, March 2005, p. 64(*)

n20 - Ibid.(*)

n21 - United States House of Representatives, Committee on Science, Subcommittee on Energy, "Fuel Cells: The Key to Energy Independence?" 107th Congress, 2nd Session, Serial No. 107-83, June 24, 2002, p. 46(*)

n22 - Ibid., p. 11(*)

n23 - U.S. House of Representatives, Committee on Science, Subcommittee on Energy, "President's National Energy Polic, Parts 1 and 2," p. 515(*)

n24 - United States House of Representatives, Committee on Science, "The Path to a Hydrogen Economy," 108th Congress, 1st Session, Serial No. 108-4, March 5, 2003, pp. 23 - 24(*)

n25 - Behar, Michael, "Warning: The Hydrogen Economy May be More Distant Than It Appears," Popular Science, January 2005, p. 68(*)

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  • Glossary - www.eere.energy.gov/afdc/resources/glossary.html

  • AAA - www.aaa.publicaffairs.com

  • U.S. Department of Energy (DOE)/Environmental Protection Agency (EPA) Fuel Economy site - www.fueleconomy.gov

  • Orange County Gas Prices - www.orangecountygasprices.com

  • Los Angeles County Gas Prices - www.losangelesgasprices.com

  • Gas Prices, All Areas - www.gasbuddy.com

  • Cars Obtaining 40 mpg - www.40mpg.org

  • EPA Green Vehicle Guide - www.epa.gov/greenvehicles.index.htm

  • California State "Drive Clean" site - www.driveclean.ca.gov

  • Drive Clean/Alternative Fuel Vehicles - www.driveclean.ca.gov/en/gv/driveclean/vtype_altfuel.asp

  • Drive Clean/Cleaner Gas Vehicles - www.driveclean.ca.gov/en/gv/driveclean/vtype_cleaner.asp

  • Drive Clean/Electric Vehicles - www.driveclean.ca.gov/en/gv/driveclean/vtype_electric.asp

  • Drive Clean/Hybrid (Electric) Vehicles - www.driveclean.ca.gov/en/gv/driveclean/vtype_hybrid.asp

  • Drive Clean/Fuel Cell Vehicles - www.driveclean.ca.gov/en/gv/driveclean/vtype_fuelcell.asp

  • Emissions Chart - www.driveclean.ca.gov/en/gv/driveclean/emissionrating.asp

  • Auto Incentives/Alt. Fuel Data Center - www.eere.energy.gov

  • GM Internal Combustion Engine Animation - www.gm.com/company/gmability/edu_k-12

  • National Fuel Cell Research Center Fuel Cell Animation - www.nfcrc.uci.edu/fcresources/FCexplained/FC_animation.htm

A special thanks to Kathy Haq, Director of Outreach and Communication, Advanced Power and Energy Program, of the University of California, Irvine, for her time and assistance during the preparation of this essay.

* * * The combined bibliography for Parts I and II of the "Green Cars" essays is available in the Essay Archives. Click here to reach the combined bibliography. * * *

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Comments? Questions? Send an e-mail to mailto:4dorothyb@dorothyswebsite.org