Hydrogen BMW fleet in Dubai, January 2001
While hybrid-electric drivetrains offer a promising path to reduced emissions and improved fuel economy, powering ICE cars with pure hydrogen is another possible approach as BMW's hydrogen-powered fleet demonstrated in Dubai recently.

Where Hybrids Make Sense - Windsor Presentation Part II

Based on Windsor, Canada presentation, September 2000

By John Wormald

In part one of John Wormald's Windsor, Canada presentation, he demonstrated that at some point in the not unforeseeable future, the demand for energy to propel the world's largely fossil fuel-based transportation system is going to outstrip the world's ability to produce that energy. This is, in part, because as nations become more affluent, their citizens increasingly shift from the use of public mass transit systems to private vehicles that consume more fuel per person per mile traveled.

Compounding the problem is the fact that as personal income rises, people also spend more of their wealth on travel and also travel further distances as clearly demonstrated by the constantly rising VMT (vehicle miles traveled) in North America over the last 20 years.

In John Wormald's view, this situation ­ along with related air quality and greenhouse gas emission issues -- will inevitably force vehicle makers to build more fuel efficient vehicles. (Of course, one pundit observed not long ago that building such vehicles only encourages more travel, so there would be no net gain either in terms of reduced congestion or fuel savings, an interesting and provocative notion).

Finding Susceptible Markets

Wormald contends that the three major drive train alternatives being investigated by automakers, only the hybrid-electric drive train offers the most promising approach to meeting the twin challenges of consumer acceptability and manufacture-ability.

To better understand where hybrid-electric vehicles make the most sense in the early stages of commercialization, Wormald showed his audience a market-segmentation slide divided in to a 12-cell matrix. The matrix consists to vehicle types ranging from passenger cars to buses and coaches in the vertical access to distance traveled in the horizontal access.

Within each of the 12 cells Wormald describes the work or task associated with the type of vehicle used and the distance traveled. A passenger car operating in the small distance segment would be used for shopping, taxis or going to school. A heavy goods vehicle operating in the medium range segment would characteristically be employed in construction, mining, agriculture, etc. Interestingly, as the range of normal operation decreases, the sensitivity to emissions and noise increases.

Wormald's company, autopolis, originally used this matrix to help define potential markets for fuel cell applications which ultimately culminated in the creation of the UNDP-funded Sao Paulo Fuel Cell bus project.

According to Wormald, "pursuing this segmentation logic, it becomes fairly clear that hybrids are the most attractive radical alternative technology in volume applications."

This is why in his next PowerPoint slide, over-the-road trucks and long-distance buses will probably continue to use conventional diesel engines because they, "operate most of the time in the most favorable part of the diesel engine operating diagram, which is hard to beat." Alternatively, however, urban transit buses are ideal candidates for fuel cell drives. "Which," in Wormald's words, "leaves the rest to hybrids, maybe except taxis, which could go (fuel cell) ­ although I concede that one to hybrids, too, especially if the vehicles are derived from mass-produced cars or light trucks." This means, light cars and trucks, as well as light commercial vehicles and local delivery trucks are ideal candidates for hybrid-electric drive train technology.

Next Wormald tackles the question of geographic markets and in his opinion, this is a "bit of a no-brainer." He sees markets for both hybrid-electric and fuel cell drive trains employed on the aforementioned platforms taking place first in the major developed nations of the world, which he divides into six major population and climate zones.

Large Advanced Temperate zone countries include the US, Canada, Australia, New Zealand, South Africa, perhaps Russia "someday", he added. Medium Advanced Temperate nations include Europe. High Density Developed nations include Japan and the so-called "Asian Tigers". High Density developing includes China and India. South and Central America, as well as "Other Poor" represent the last two groups. He sees the internal combustion engine continuing its roll in all these zones in both over-the-road truck and long-distance bus use. It will also continue its dominant role in all other vehicle classes in the High Density Developing nations, Central-South America and the Other Poor.

But in all of the developed nations, where fuel consumption is the largest, both hybrids and fuel cells can play an important role. This is especially true in the Large Advanced Temperate zones, which consumes more than twice as much fuel annually as the Medium Advanced Temperate where higher population density and smaller geographic distances are reflected in different driving patterns.

A Plethoria of Architectures

Wormald told his listeners that what strikes him most about hybrid-electric technology is its "potential flexibility".

"In theory at least, one can have multiple combinations. The amount of power stored can vary from 0% to 100% electric ­ well, 10% to 90%, in practice. We can have series or parallel drive. If we go series drive, then we may choose a central motor or individual wheel motors, although I suspect the latter are really only interesting for low-floor buses and special vehicles, such as diesel-electric mining trucks."

"In parallel drive, we have to choose a mechanical transmission; presumably something controllable, such as a CVT (continuously variable transmission). We may combine the electric motor and generator into one unit, in the case of parallel drive, or not."

Wormald emphasizes that which every architectures eventually become predominate, it will, most likely, not be traditional automotive parts vendors who supply the electric and electronic components for such systems, simply because of the nature of the technology involved. (Editor's comment: This should bode well for firms like UQM Technologies, Enova Systems, EcoStar, EXCELLSIS, Capstone and others).

"In practice, I believe we are likely to see grouped sets of solutions emerging, simply to get the economics of scale in componentry," Wormald told his audience.

His next slide indicated the range of hybrid-electric configurations available. He divides them into the percentage of energy derived from battery and/or flywheel stored energy from 0% for pure ICE vehicles to 100% for pure battery or direct hydrogen fuel cell electrics.

He suggests that there are still many options available to the pure ICE for both emissions and fuel efficiency improvements, including the use of indirect and direct fuel injection, diesel and alternative fuels. One good example is BMW's work on a hydrogen-powered ICE, a small fleet of which is currently on a world tour that started recently in the Arab sheikdom of Dubai.

Wormald's next category is what he calls "electric boost" with electric power contributing less than 30% of energy needs. This is the direction currently be taken with the development of "lite hybrids" utilizing the new 36/48 volt power systems.

True hybrids, in Wormald's view, derive 30% or more of their power from battery or flywheel energy storage. This is what he calls the "Prius-type" vehicles, but which also has the added ability to operate in an all-electric mode during the urban-driving cycle. He still sees the ICE as the dominant power source in a parallel drive configuration for this class of hybrid.

He sees mainly specialized urban vehicles such as delivery trucks falling into the next category that would derive 70% of their power from battery/flywheel energy storage.

Finally, he sees vehicles that are in the 90% and above range having only limited application such as golf cars, airport GSE and perhaps specialized delivery vehicles. "The California experience indicates pretty clearly," he states, "that the (pure battery EV) is, in my opinion, a non-flyer, except in limited radius applications... The German Rugen Island test indicates that the environmental benefits are questionable."

Market Timing

When does Wormald see a serious market developing for these technologies? Disappointingly, not for another 30 years. He attributes this to "fuel availability and price situation." He estimates that the marketplace won't really get started until 2010 and begin a slow but inevitable ascent from then on, reaching nearly a 100% market penetration by about 2040. The alternative power train passenger car market won't catch fire, in his view, until about 2030. This is, "essentially because of the inertial resistance of low-cost mass production of conventional vehicles, particularly cars and light trucks."

"Nor do I see a full hydrogen economy coming during that time frame, which could simply abort the whole hybrid project," he adds.

He estimates the potential size of the various markets as follows : (Projected growth of new driveline technologies in thousand units/year)

 20002010 202020302040
Hybrid car/LT 0 0 2,700 22,50050,500
FC Taxis 025 200 450550
Hybrid LCV 0 350 2,500 8,00014,500
Hybrid Local Trucks 0 30 350 1,3002,500
FC Urban Buses 00.9 35 100150

Wormald cautioned that he felt this kind of time frame was necessary "for enough of a head of environmental steam to build up" and for production to ramp up and component costs to come down. "And that's not just the hybrid driveline," he added, "but also the lightweight bodies that go with it."

In Summary

He summarizes his views as follows:

"However, he cautions, "(this is) absolutely not an excuse for not pursing development."

Times Article Viewed: 4351
Published: 17-Feb-2001


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