Andy Frank, UC Davis professor
Professor Andy Frank at California Fuel Cell Partnership open house in 2001. He is a strong advocate of plug-in hybrids.

Andy Frank's Plugged-In Vision

Part one of interview with UC Davis professor on merits of plug-in hybrid electric vehicles.

By Bill Moore

There are some folks you just can't help but like first time you meet them. For me one of those people is Dr. Andy Franks, professor of engineering at the University of California at Davis.

I first remember him as the outspoken advocate of EVs at a conference in Phoenix, Arizona. I have since bumped into him many times at various electric vehicle events from FutureTruck to the California Fuel Cell Partnership open house. And we occasionally correspond through email.

His UC Davis FutureCar and FutureTruck teams have consistently placed in the top rankings of these competitions, so he does more than theorize about EVs, he and his students make it happen.

So, when he wrote me an email about the inefficiencies of making hydrogen compared to storing electric energy in batteries, I decided to ask him his views not only plug-in hybrids -- one of his favorite topics -- but also on the hydrogen economy. We talked for nearly an hour and what follows, along with the streaming audio link at right, is the result of that conversation.

I began by asking him to explain the concept of a plug-in hybrid electric vehicle (PIHEV) and why he thinks this is the direction automotive engineers should be going, though none of the big carmakers are at present.

It is his theory -- as demonstrated in UC Davis' latest Ford Explorer FutureTruck -- that consumers will not only reap the benefits of lower operating costs, but also improved performance going the plug-in hybrid route. Basically, what he advocates is dramatically downsizing the gasoline engine, while increasing both the size of the electric motor and battery pack.

Historically, the automotive industry has balked at this strategy because they claim it adds weight and cost to the vehicle.

Professor Frank counters that not only will his plug-in hybrid Explorer weight nearly the same as a conventional Explorer but more importantly, it will have more power, to the tune of 330 horsepower when the gasoline engine and electric motor outputs are combined. He jests that not only will his vehicle pull anything a V8 Explorer will pull, but that his vehicle might just pull the hitch right off the frame.

As for added cost, he tells EV World that according to his estimates, a plug-in hybrid system would add only 10-15% to the total price of the car, comparable to the cost of adding leather seats and a sun roof. This is due, in part, to the use of newer, more powerful and cheaper Phase III NiMH batteries built to custom specifications for the UC Davis team by Ovonics. He estimates these new batteries will last 150,000 miles because of the university's battery management system.

While most consumers aren't that concerned about emissions, Frank also notes that the plug-in or grid-connected hybrid also reduces emissions considerably, even if you take into account the sources of the electricity. He points out that he and his students have looked at the emissions issues and well-to-wheel efficiencies of this approach not only for California and the West Coast where much of the electricity is generated by hydroelectricity, natural gas and even renewables like wind and solar, but also in the American Midwest and East Coast, which depend more on fossil fuels and nuclear power.

However, he asserts that plug-in hybrids make sense in all these areas because of the power industry's shift towards the use of cleaner fuels like natural gas and more modern coal-burning power plants, which are gradually phasing out older, dirtier systems.

Plug-in Theory
The principle behind PIHEVs is that instead of using the energy from a small battery pack to assist the IC engine, the PIHEV uses a larger battery pack to provide all of the traction power for ranges between 20 and 60 miles, depending on the vehicle and size of the pack. The IC engine only starts to operate once the vehicle reaches the limits of its designed zero emission vehicle (ZEV) range. Such a vehicle would have nearly all the attributes of both a completely battery electric car and a gasoline-powered car. For most commuters, the car would generate no local emissions.

Such cars would use electric power -- generated from America energy sources -- for most of their daily driving needs, offering a very practical way to reduce American dependence on imported oil, improving our national security, reducing our trade deficit, and cleaning up the air locally.

Frank envisions consumers charging their vehicles at night using off-peak power. He calculates that the operational costs of such a vehicle would be one-sixth that of gasoline car. And this doesn't include reduced maintenance costs because the plug-in design eliminates the need for many power-robbing components and accessories.

Carmaker's like Honda and Toyota have stressed in their advertising messages that you don't have to plug in their hybrids to recharge them. This is intended to assuage consumer misconceptions that the car will not run if it runs out of electricity even though it has a gasoline engine.

From Frank's perspective -- and many battery electric car drivers and California regulators -- this may have helped sell cars, but it fails to point out that plugging in your car at night actually can save you a LOT of money! Dr. Frank estimates you can run a plug-in hybrid for the equivalent of 50 cents a gallon of gasoline! Gasoline in California, he noted, is now over $2 a gallon and climbing. He says that the plug-in hybrid will run just fine without plugging it in, consumers just have to buy more gasoline.

PIHEVs are beginning to look very appealing just on pure economic grounds!

Plug-in Range
Dr. Frank says that computer modeling at UC Davis indicates that PIHEVs can have pure ZEV ranges of anywhere from 20 to 60 miles without changing the weight of the vehicle. He says he can do this by adjusting the size of the IC engine to the size of the battery pack.

The UC Davis FutureTruck Ford Explorer is currently about 300 pounds over stock Explorer weight of about 4,500 pounds. He says that one of the tasks for this year's team is to cut weight and bring the vehicle back down to the stock weight. They will do with by lightening various components in the vehicle like the tailgate and seats.

"We're not weakening anything, but swapping materials" he emphasizes.

He tells EV World that if he were able to design the vehicle from scratch, he could keep it at its same weight while further improving its performance, operating costs and emissions. This is partly due to the fact that the weight distribution in the vehicle is now evenly spaced between the front and rear, unlike the currently front-heavy conventional Explorer.

One of the newer innovations Frank is investigating is a dramatically downsized charging system on-board the vehicle. He says he and his students are looking at a simple 110-volt charger that will take 10-12 hours to completely recharge the vehicle, basically from the time the vehicle gets parked in the family driveway or garage in the evening until its driven away to work the next morning. This will reduce the complexity, weight and cost of the system and eliminate the need for an extensive public charging infrastructure. All you need to recharge the batteries is a common 110-120 volt AC outlet, usually readily available in most garages.

Professor Frank points out that over a decade of experience with batteries at UC Davis shows that they are highly complex devices that require careful monitoring and management.

"They have to be intelligently managed," he says. When they are, they can last the lifetime of the vehicles, he contends. He also notes that since doing a cost study two years ago, the price of advanced batteries has dropped even further.

Comparing Emissions and Costs
I asked Dr. Frank about Toyota's contention, as expressed by our mutual, UN-retired friend Dave Hermance, that when comparing well-to-wheel emissions within a typical urban drive cycle environment, that the non-ZEV range hybrid like the THS-equipped Prius -- has a lower overall emissions than a PIHEV.

Frank teased his colleague by saying statistics can be spun to prove any point and Frank's "spin" shows that plug-in hybrids generate fewer emissions, especially as the size of the battery pack increases and the range increases.

An obvious question that any thinking person will ask, is if everyone starts to recharge their PIHEVs -- assuming that carmakers actually begin to offer them for sale -- from the grid at night, won't we run out of power?

Franks responds that he and his students have very carefully looked at this issue, especially since it is such animportant one in California, in the wake of the energy crisis of 2001. UC Davis studies show that the current power grid can easily support up to 10% PIHEV fleet penetration without having to build new plants or capacity. He says it will take years to reach this level of penetration, after which time, new base-load generating capacity will have to be built, but the net effect of this will be to actually reduce the cost of electricity, rather than increase it.

In addition, when coupled with a bidirectional, vehicle-to-grid (V2G) charging system that enables the power company to pull power out of vehicle batteries during peak load times, the cost of electricity will drop even further because now the fleet of PIHEVs become peak shaving devices. As EV World has suggested in the past in interviews with other V2G proponents, there is the distinct possibility that the power company will even pay car owners for the use of this energy, turning a historically depreciating asset into a potential income generating asset.

Suddenly PIHEVs with V2G capabilities look even more attractive!

Part Two Continued Next Week....

Times Article Viewed: 34426
Published: 02-Mar-2003


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