CARB: hybrids okay as ZEVs
The California Air Resources Board (CARB) upstaged the Society of Automotive Engineers (SAE) mobility conference in Costa Mesa, CA, in August by opening the door for hybrid electric vehicles (HEVs) to qualify for credit toward the state's 1998 zero emissions vehicle (ZEV) regulations.Until now, CARB had said that only vehicles with no internal combustion engine - in essence, then, only battery-powered
September 1, 1995
The California Air Resources Board (CARB) upstaged the Society of Automotive Engineers (SAE) mobility conference in Costa Mesa, CA, in August by opening the door for hybrid electric vehicles (HEVs) to qualify for credit toward the state's 1998 zero emissions vehicle (ZEV) regulations.
Until now, CARB had said that only vehicles with no internal combustion engine - in essence, then, only battery-powered electric vehicles (EVs) - would be classified as truly zero-emitting.
While SAE speakers discuss advances and new limitations in EV technology in a separate meeting in El Monte, CARB hears staff proposals to allow HEVs to qualify for at least partial credit toward meeting the ZEV requirements. If approved by the board early in 1996, the proposals would be the first changes in California's sweeping ZEV regulation since it was adopted in 1990. The regulation currently calls for high-volume manufacturers to sell ZEVs in numbers equal to 2% of their California light-vehicle sales beginning in 1998 and for all manufacturers to sell ZEVs equal to 10% of their California volume by 2003.
Under the new proposal, CARB would allow partial credit for HEVs. An HEV that could travel at least 50 miles (80 km) as a pure electric before switching to its conventional fuel-burning mode would get up to 79% ZEV credit if its emissions are lower than the amount of pollution created by powerplants generating electricity.
CARB and state officials have been under intense pressure from the seven manufacturers who must launch ZEVs by 1998 (Detroit's Big Three and the four largest Japanese automakers) to ease the restrictions or at least delay the ZEV implementation plan. They maintain that EV technology is still too primitive for them to have marketable EVs by 1998.
The CARB proposals are the first break in the state's no-compromise position, but it's not what Detroit was looking for. The initial manufacturer response to the CARB proposals was that they don't provide significant relief for the automakers that must meet the 1998 deadline. However, NEVCOR, a start-up California company founded by a Stanford University professor to produce HEVs, is delighted.
Automaker concerns about the state of EV technology were underscored at the SAE's Future Transportation Technology Conference.
Two reports from the University of California at Davis reveal that in real-world experience, the effective life cycle of EV battery packs and the range of EVs were markedly less than theoretical projections assume.
A dozen papers on EVs delivered at the conference paint a picture of an emerging industry just beginning the transition from experimental and research vehicles to the design and development of production vehicles. The focus of the SAE papers is shifting from EV research to EV design. Among the major findings:
* Steyr Daimler Puch Fahrzeugtechnik, the R & D arm of the Austrian specialty vehicle maker, says it has developed an advanced, optimized EV drivetrain that integrates an electric motor, electronic controller, charging system, transmission and final drive. It uses a fully automatic 2-speed transmission, which the company says substantially cuts cost and weight by reducing the need for a large motor and concentrating on efficient use of battery power.
* Motorola Inc. reports that current multiplexing technology can be successfully used in EVs, despite the intense electromagnetic interference (EMI) generated in EV designs. This suggests that multiplex vehicle communication systems developed for conventional vehicles under SAE standard J1850 can be used for EVs as well; that would allow the weight savings of multiplexing to be applied to EVs without developing a separate protocol. A second Motorola paper reviewed EV motor-drive electronics and suggested possible improvements with advanced semiconductor technology and designs.
* A.F. Burke of UC Davis says real-world battery life is often much shorter than expected for EVs because of variations in voltages among battery-pack modules, which leads to premature failure. He notes that EV battery performance often begins degrading within a few months or a few thousand miles and that the life of the battery pack dramatically affects EV operating costs.
* A second UC Davis paper confirms through real-world EV testing that battery pack life is substantially less than expected, sometimes dramatically so, and that EV ranges are typically half of what is expected. Testing on three types of EV battery packs from Solectra and U.S. Electricar showed that the battery packs were very sensitive to uneven cell capacity, improper charging and temperature differences between modules. Authors Blake E. Dickinson and David H. Swan recommend development of flexible, programmable battery-management systems that can prevent voltage differences between modules from worsening and leading to premature failure.
* Argonne National Laboratory reports preliminary results from a Delphi study it conducted on the long-term future of EVs and HEVs. The key results include a forecast that EVs and HEVs will capture 20% of the new vehicle market by 2020, with prices still slightly more than gasoline cars and performance equal to a 1993 gasoline vehicle. Through 2000, EVs and HEVs are projected to have inferior performance and range than a 1993 vehicle - with costs 50% to 100% higher.
While the technical aspects of EVs and HEVs are coming along slowly, manufacturers are under the gun to start marketing ZEVs in California in little more than two years. The 1998 deadline directly affects only the Big Three and Toyota, Nissan, Honda and Mazda, but other manufacturers also are feeling the pressure.
"We can't wait until 2003 to start marketing a California ZEV," says a senior product planner for one Japanese automaker. "Everybody has to sell ZEVs equal to 10% of their California volume by then, but if we don't get started well before 2003, the big guys will have sewn up the EV market completely, and we're locked out."
The proposed new CARB regulation may not significantly widen the options for manufacturers who must commit to a vehicle design for 1998. Most manufacturers' HEVs, although they can in theory use more time-proven components, currently are not any closer to market than battery-powered electric vehicles.
THE HYBRID
DRIVETRAIN
1 Fuel: Gasoline, Diesel, Methanol, Ethanol Compressed Natural Gas, or Hydrogen. 2 Primary engine: Fuel cell, gas turbines, and internal combustion engines run at a constant efficient speed and could be used to generate power to electric motor and energy storage devices. 3 Controller: Controls the energy flow into and out of the battery bank. 4 Energy storage: Advanced batteries, flywheel, or ultracapacitor. 5 Electric drive: Primary drive motor used for acceleration. 6 Regenerate braking: Recovering braking energy and reusing it to accelerate.
SERIES OR PARALLEL ARRANGEMENT
Series arrangement uses primary engine as generator for electric motor.
Parallel arrangement uses multiple engines as driving forces.
Better quality gasoline sought by Big Three
GM, Ford and Chrysler, working through the American Automobile Manufacturers Association (AAMA) have developed a four-page list of tightly defined specifications for gasoline (revised June 30, 1995) that is expected to improve both vehicle performance and durability.
Just how the specifications - that go well beyond those of today's so-called refolmulated gasoline (RFG) - will be carried through to customers by gasoline refiners and marketers has not been announced, but a Big Three engineer tells WAW one possibility is for some type of "approved" or "certified" logo to appear on gas pumps that dispense gasoline meeting the new specifications.
Another possibility is suggested in a Nov. 18, 1995, letter from General Motors Corp.'s then Vice Chairman, Harold Kehrl, to petroleum companies; GM seeks better-quality gasoline "in order to reduce deposits that impair performance of GM fuel injectors."
In his letter, Mr Kehrl specifically cites Mobil Oil Corp. as "presently marketing and advertising gasoline with improved quality" and expressed the hope that other would do the same so that GM can inform its customers.
The principal difference in the situation this time is that the gasoline qualities sought by the Big Three are not only aimed at the problem of fuel injector deposits - but rather at a much broader spectrum of factors, such as the negative impact on "driveability," the effects of reduced volatility, the corrosive effects of sulfur, alcohols and alcohol/water mixtures, and the need to prevent fuel injector plugging.
The AAMA specifies a long list of other factors related to gasoline properties, including lead, manganese, silicon, phosphorous, gum, olefins, aromatics, oxygenates, contamination, water and octane.
The one ingredient in gasoline without a specified limit is sulfur, which could be very expensive to remove to the same degree currently required by California, 40 parts per million versus an average of about 40 ppm in the other states.
One gasoline refiner and marketer that agrees that quality is a concern is Citgo Petroleum Co., which distributes a two-page advisory to a meeting of recreational marine dealers in late July in which it says, for instance, that "gasolines now contain more benzene, toluene, xylene and olefins, which burn dirtier, and olefins are unstable in storage, causing formation of gum in gasoline and varnish-like deposits in engines."
A Citgo spokesman explains that these comments refer mainly to gasoline sold in non-RFG areas (although RFG has certain of its own problems).
Petroleum engineers explain that pipeline (fungible) gasoline can be made from greatly differing crude oils at refineries with similarity varying capabilities, resulting in disparate product quality.
BMW AG, for one, recently has experienced some fuel-related engine problems with its 3L and 4L all-aluminum V-8s; high sulfur-content U.S. gasolines can erode the engines' nickel-silicate cylinder-bore treatment. A BMW spokesperson says that gasoline sold in the U.S. ranges from good to some of the worst in the world. Some engine-powered equipment firms agree, and warn their customers to "use only namebrand gasoline."
Apparent problems with some of the gasolines marketed in the U.S. have increased the need to more carefully consider the impact of changes in fuel composition and quality.
Fuel composition and quality have become more than a passing concern at GM, which touts one of its 1996 engines as updated with "stainless-steel fuel injectors, for improved corrosion resistance with alcohol-additive fuels."
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