Driving the debate
- By Hu Fleming
- Sep 01, 2000
This is the second in a two part series of articles. Part I, which appeared in our June 2000 issue, examined the pros and cons of alternative fuels.
The Partnership for a New Generation of Vehicles (PNGV) was designed to be the doorway for American automobile manufacturers to enter into a new age of technological and environmentally advanced automobiles. Created Sept. 29, 1993, PNGV participants included seven federal agencies, national laboratories, universities, suppliers and a cooperative, pre-competitive research effort the United States Council for Automotive Research (USCAR) between the Big Three automakers: DaimlerChrysler, Ford Motor Corp. and General Motors (GM). This unique partnership formed by government and private industry was to pave the way for the "supercar" of the 21st century a vehicle providing safety, performance, affordability and comfort, all while reducing dependence on foreign oil through improved fuel economy and alternative fuel use and lessening the impact of cars and light trucks on the environment.
Fuel cells offer the possibility of ZEVs with a nearly limitless supply of fuel.
A second goal of PNGV is to improve the competitiveness of American automobiles in the world market. "If the U.S. is going to lead the world, then clearly it is going to require a move away from gas burning cars to automobiles that use new types of power trains and fuels," Natural Resources Defense Council senior attorney, Jacob Scherr said. PNGV's supercar (Table I), scheduled to be in the production prototype stage (the last stage prior to mass production) by 2004, is already losing ground to foreign competition. Two alternative fuel vehicles (AFVs), closely mirroring the standards set out for PNGV's supercar, have already entered the U.S. consumer market: the Honda Insight (Jan. '00) and the Toyota Prius (July '00). Both Honda's and Toyota's AFV utilize a hybrid drive system that combines an internal combustion engine (ICE) with a battery-powered electric motor. The hybrid technology allows both automobiles to achieve increased fuel efficiency and lower emissions while maintaining quality perform
Table I. PNGV "Supercar"
|An environmentally friendly car, with up to triple the fuel efficiency of today's midsize cars without sacrificing affordability, performance or safety.
Concept vehicle to be available in approximately six years (1999) and a production prototype to be available in approximately ten years (2004).
- Curb weight: up to 40 percent weight reduction over baseline (3200 pounds);
- Aerodynamics: 0.20 Cd (drag coefficient) (Innovative styling, shielding);
- Friction (rolling resistance): 0.005 (Improved tires and friction management);
- Fuel efficiency of up to 80 mpg (Metro-Highway);
- Meet Tier II emissions at default levels of .125 HC, 1.7 CO and .2 NOx at 100,000 miles while complying with other Clean Air Act requirements; and
- Recyclability of at least 80 percent - up from today 's 75 percent industry average.
Quick fact I Innovative braking system helps minimize and recapture the energy lost when slowing down or stopping a vehicle. The kinetic energy lost as heat in a friction braking system is reclaimed and used to partially recharge the battery system.
"It's no question the recent hike in gasoline prices shows once again why it's so important for us to push hard to get not just gradual, slow improvement in efficiency, but dramatic improvement," Vice President Al Gore said. "We have to recognize the importance of moving quickly." While foreign markets have taken the lead in AFV development, American manufacturers are still in the race. The most important issues facing these manufacturers are the decisions to be made concerning which technologies will prove most viable in supercar creation.
Electric vehicles (EVs) have long held promise as a potential solution to the pollution caused by small cars and trucks. Known as zero emission vehicles (ZEVs), such automobiles produce zero by-products during operation, and although emissions do occur at the power plants used to produce the energy for charging an EV's batteries, the vehicles are still approximately 95 to 97 percent emission free. It is much easier to control and decrease emissions from a large power plant than from numerous individual sources.
According to the Electric Vehicle Systems Association, approximately 85 percent of the cars in the United States are driven less than 20 miles a day. With a typical EV capable of traveling from 40 to 70 miles on a single charge, such vehicles fit well into a niche market of consumers looking for a vehicle to handle their daily commute, but further travel would require breaks for battery charging. Advantages of EVs are:
- they require no tune ups or exhaust or emissions tests;
- feature silent operation; and
- they cost 60 to 75 percent less to operate.
The Big Three automakers each offer EVs to American consumers. GM's EV1, Ford's Ranger electric and DaimlerChrysler's EPIC minivan are all ZEVs with the option of a lead-acid (PbA) battery pack or a nickel-metal hydride (NiMH) battery pack. The PbA batteries typically require a charging period of five to six hours with a range of 50 to 60 miles per charge. Such batteries are 98 percent recyclable. The lead can be melted down and reused, the plastic case is shredded and recycled and the acid is naturalized and can be made into fertilizer.
NiMH batteries require a longer charging period (six to eight hours) and are bulkier and more costly than PbA batteries, but they allow for greater performance over a longer distance. NiMH EVs will travel between 70 to 130 miles per charge. EVs hold the potential to dramatically cut greenhouse gas emissions from small cars and trucks, but until improved battery technology increases range and performance while lowering costs, EVs will continue to serve only a minor, niche market of consumers.
Quick fact II
Although not seen as a viable alternative in the immediate future, innovations in photovoltaic cells and improvements in battery storage capacity have helped solar cars reach new highs. The world-speed record for solar powered cars was broken at SunRace 2000 in Australia (Feb. '00). Four vehicles traveled the 100-kilometer (62 miles) course at an average speed exceeding 100.9 km/hour (62.55 mph).
AFVs operating on fuel cell technology potentially offer comfort and performance equal to contemporary automobiles, as well as zero emissions and increased fuel economy. The key component of fuel cell technology is hydrogen. As long as hydrogen is fed into a fuel cell, the battery-like unit will continue to produce by-products of water, heat and electricity. Consisting of two electrodes a cathode and an anode on either side of an electrolyte, fuel cells produce electricity when hydrogen and oxygen pass over their respective electrodes and react in the electrolyte. The chemical reaction replaces the combustion process of an ICE, thus eliminating harmful emissions. As hydrogen is the most abundant element on earth, fuel cells offer the possibility of ZEVs with a nearly limitless supply of fuel.
However, current technology, limits the advancement and performance of fuel cell vehicles. Fuel cells are getting smaller, but their current bulkiness limits their consumer use to large vehicles such as buses and other forms of public transportation. In addition, the source of hydrogen for fuel cells remains a point of contention. Hydrogen gas and liquid hydrogen are incompatible with existing infrastructures and not feasible for mainstream use. Large amounts of hydrogen cannot be stored safely or effectively for use in small cars and trucks. A fuel cell system that includes a fuel reformer a device that separates hydrogen atoms from molecules through a chemical process is able to strip hydrogen from any hydrocarbon-based fuel (natural gas, gasoline, methanol, etc.), and by utilizing existing fuel infrastructures, fuel cells are made more viable. The stripping of hydrogen from hydrocarbon-fuels does release greenhouse gas emissions into the environment, but stripping hydrogen fro
m gasoline or
natural gas would still reduce current greenhouse gas emissions by 20 to 70 percent. "To backslide now, and run these remarkable cells on gasoline because that infrastructure exists, will be to violate a remarkable and historic opportunity," Dr. Robert J. Wilder, Conservation Director at Pacific Whale Foundation said.
Fuel cell technology is still in the conceptual stage as far as the Big Three automakers are concerned. Each has already unveiled a concept car driven exclusively by fuel cell technology, with production-ready vehicles to be available by 2004. Their fuel cells will most likely use reformers to strip hydrogen from gasoline or methanol. "Fuel cells can offer a true breakthrough in 21st century power generation combining high power generating efficiencies with superior environmental performance," U.S. Energy Secretary Bill Richardson said.
Early this year, GM, Ford and DaimlerChrysler debuted their latest concept vehicles as developed under PNGV. All three supercars utilize hybrid technology and innovative design to reach their goal of a fuel efficient, family-sized sedan that doesn't sacrifice safety or comfort. "Hybrid electric vehicles represent a potential near-term solution for improving fuel economy, and in most cases, improving emissions," GM President and Chief Operating Officer, G. Richard Wagoner, Jr., said. GM's Precept, Ford's Prodigy and Chrysler's ESX3 all feature a diesel powered ICE and electric motor hybrid system with NiMH battery packs. Although using diesel fuel, each supercar achieved approximately 70 miles per gallon (mpg).
Honda Insight and Toyota Prius
|The first gasoline-electric hybrid powered car available in the United States.
||The world's first mass-produced hybrid vehicle (Japan 1997) became available in the United States in July.
- Powered by a 1.0 liter, 3-cylinder gasoline engine and a nickel-metal hydride battery-powered electric motor;
- Fuel efficiency of 61 miles per gallon (mpg) city and 70 mpg highway;
- Aluminum frame is approximately 40 percent lighter than a comparable steel frame with a curb weight of 1,887 lbs.;
- Aerodynamics: 0.25 Cd (drag coefficient); and
- Meets California's Ultra Low Emission Vehicle (ULEV) standard.
- Powered by a 1.5-liter DOHC 16-valve, 4-cylinder engine and a nickel-metal hydride battery powered electric motor;
- Fuel efficiency of 52 miles per gallon (mpg) city and 45 mpg highway;
- Curb weight of 2,765 lbs.;
- Aerodynamics of 0.29 Cd (drag coefficient); and
- Certified as a Super Ultra Low Emission Vehicle (SULEV) 75 percent cleaner than the standard for Ultra Low Emission Vehicles (ULEV)
All three concepts have taken advantage of new, lightweight materials, regenerative braking and improved battery performance to meet their goals. Production models based on the three supercars are slated to be ready by 2004. The Big Three are behind Japanese car manufacturers who delivered their hybrid vehicles to U.S. consumer markets this year but they have also been waiting to see if Americans would be willing to pay more for a fuel-efficient car with a hybrid engine, despite low fuel prices that make fuel efficiency less valuable here than in other parts of the world.
Along with consumer concern over the cost and instability of fuel prices as well as the growing awareness of long-term fossil fuel limitations automotive innovations and technological advances are speeding up interest and excitement in AFVs. "By reducing our dependence on foreign oil; by reducing pollution throughout our economy; and by positioning the American auto industry as the world leader in a crucial market in this new economy the Partnership for a New Generation of Vehicles can help to keep our economic engine humming for decades to come." Vice President Gore said. Consumers interested in improved fuel efficiency and environmentally safer transportation will be turning to AFVs as manufacturers continue to make them more available and equitable to today's automobiles.
Partnership for a New Generation of Vehicles www.ta.doc.gov/pngv/cover/pngvcover.htm
The Alternative-fuel Vehicle Directory www.vwc.edu/library_tech/wwwpages/gnoe/avd.htm
Alternative Fuels Data Center www.afdc.doe.gov
This article appeared in Environmental Protection, Volume 11, Number 9,
September 2000, Page 30.
Click here to post comments about this topic and read what others have to say.
This article originally appeared in the 09/01/2000 issue of Environmental Protection.