by Dr. John S. Dunning

The rise in gasoline prices has again ignited interest in electric cars. After all, who wants to pay more for fuel? Who wants to contribute to global warming? Who wants to pollute the air? The fact is that electric cars will eventually provide energy independence and will use clean, renewable solar power to help us get around. In the 1960s, when air pollution got to be intolerable in Los Angeles, control devices were forced on the auto industry. At that time, other engines and electric propulsion were investigated by the auto companies, but never became competitive. Why haven’t they caught on?

The simple reason: gasoline is a very energy dense fuel compared with batteries, so a car running on gasoline has the ability to provide much greater range, quick refueling, and many energy-consuming amenities (e.g., air conditioning, trailer hauling, interior room for passengers and cargo) that drivers love. Even though the electric power train, with a simple motor (1 moving part) and an electronic controller is much more efficient in converting stored energy into motion than is the gasoline engine and conventional transmission, the additional efficiency cannot overcome the tremendous stored energy advantages of liquid fuel. This is especially truce since the past 100 years have seen the development of infrastructure (gas stations, interstate highways instead of railroads, refineries, the global shipping of oil) that favors the liquid fuel technology. We have been spoiled, if you will, by low-cost petroleum fuels. We have been able to add enough pollution-control devices to make tolerable the air in places like Los Angeles, where smog alerts have become rare. We hear about global warming as a consequence of petroleum fuel use, but feel helpless to do something about it as individual consumers. So the poor old electric car is unable to break into the mainstream of auto consumer consciousness and remains a toy for visionary thinkers.

Is there hope? Let’s take a look at recent developments in electric cars and see what’s new. We’ll start with the GM EV-1, a two seat sport commuter built in the years between 1996 and 2000. About 1,200 of these cars were leased to customers in California and Arizona. They used an efficient but expensive alternating current induction motor drive system, highly advanced aerodynamic and expensive light weight material body systems, advanced lead acid and nickel metal hydride batteries, and a unique contactless charging plug. The combination of higher power (135 hp) and high torque at all speeds from the drive system along with low vehicle mass made these cars very responsive, fast, and fun to drive. They were also very quiet. The customers were given very generous lease terms of $350 to $500/month and the company assumed all risk of battery failure and problems associated with new technology. As a result, the customers, in general, were delighted with the cars. Most used them every day for commuting (the range between charges was about 100 miles with lead acid batteries and 150 miles with nickel metal hydride batteries. The cars were simple to charge and GM worked with local utilities to put charging stations in homes and around major towns. Customers never visited gas stations. Their electric bills usually were only nominally increased, and they felt very special. They were living clean, silent, and free from gasoline. The engineering team at GM that developed the cars, the manufacturing team that produced the cars, and the Saturn marketing teams that sold and serviced the cars became delighted too. They had produced something really special.

Unfortunately, rain began to fall on the parade. The cost of building the car was never divulged, but must have been over $50,000 without batteries. The nickel metal hydride battery that provided comfort about running out of range costs about $500/kWh in mass production (GM paid much more) and since the car carried about 30 kWh of energy storage, the battery cost was $15,000. (The number of kilowatt hours (kWh) indicates how much electric energy is stored in a fully charged battery.) So a total vehicle cost of $65,000 is a reasonable estimate. Normal lease cost on such a vehicle would be at least $1,000/month, so the company was eating $500/month in losses. In addition, the California Air Resources Board (CARB) had mandated that GM produce 10% of its sales to be Zero Emission Vehicles (ZEV). That program, if adopted nationwide, would mandate 500,000 cars a year and produce a loss of $3 billion per year. No wonder GM balked at having such a mandate and fought it in court. GM won the battle and CARB backed off the ZEV mandate. Then, GM pulled the cars from the market when the leases expired in 2003, prompting a protest movement from fans and lessees of the EV-1, the rise of which is detailed in the delightful film, Who Killed the Electric Car? In the film, cleverly cast as a murder mystery, the saga is quite nicely summarized and blame is assessed. Interestingly, both GM and CARB are found guilty by the makers of the film, but the real guilt lay with the cost of the technology.

Fast forward to today. We now have newer batteries, called lithium ion batteries. The batteries are used in your laptop computer and cell phone and are produced by the millions. They store twice as much energy per pound as nickel metal hydride, and cost about the same per kWh stored. So now we can build a high performance car with a 200+ mile range. Such a car is the tZero, a very low volume sports car developed by AC Propulsion. (Alan Cocconi, the founder of AC Propulsion, was the chief designer of the GM prototype drive train, later modified for the EV-1.) A new company, Tesla Motors, has taken the concept further and developed a beautiful roadster, using a Lotus Elise body and elements of Cocconi’s drive train. These vehicles go zero to 60 mph in about 4 seconds and cost about $100,000. Battery life is unknown. Your computer batteries last a few years but usually you change computers without worrying about laptop battery. In the case of the Tesla, with over 50 kWh on board, battery replacement might be $25,000 after 2 or 3 years. However, if you’re paying $100,000 for a 2-seat sports toy, you probably don’t worry too much about such things. If I could afford it, I would love to have a Tesla. Tesla has announced that all of its production is sold and is taking orders on a waiting list. If GM could only do the same!

The high end of the electric vehicle market as discussed above, is alive and well. What about the low end? The low end is the electric bicycle and motor scooter market in Asia. Here, millions of people cannot afford cars so they ride about on bicycles (extremely energy efficient vehicles). The addition of a low cost lead acid battery and a low cost direct current motor can make a bicycle much easier to ride. So the range and payload is increased by making them electric. Of course the cost also rises, but the income levels in Asia are also rising more rapidly than the costs, so the market is taking off. A recent study indicates an annual market of 30 million electric bicycles in China alone. Apparently, the drivers can recharge by removing their battery and taking them into their apartments, so enough infrastructure is available to make this market work. These customers would love to have cars, but they cannot afford them yet. Lead acid batteries were the initial choice, but recently lithium batteries are penetrating this market. China’s battery industry will become the world leader due to this phenomenon.

Beyond the two wheel market is the so-called city car or neighborhood electric vehicle. These vehicles are like modified golf carts or other familiar service vehicles. Examples include TATA motors in India, the Think vehicle, the electric Smart vehicle in Europe, and the GEM vehicle. The range is about 25 miles, and the speed is about 35 miles per hour. Amenities are sparse and they do not mix with traffic on freeways or highways. However, many markets can be served by such vehicles, especially in developing countries and in restricted neighborhoods in developed countries.

Finally, let’s consider hybrid electric vehicles (HEV). In the past few years, starting with the Toyota Prius and Honda Insight, hybrid vehicles have gone from nowhere to being the hottest must-have technology in the automotive sector. The Prius combines a battery with electric motors and a conventional engine to manage the energy in the vehicle. The engine and the batter both operate in their most efficient ranges. Also, the battery recovers some of the energy normally wasted by braking through operating the motors as generators. These vehicles normally do not plug into the electric power grid and only use the battery to improve the fuel efficiency of the drive system. Toyota has cleverly managed the cost of the Prius and probably lost money on it for a number of years.

Recently, Chevrolet announced that it will introduce a new concept, called the Volt. In this car electricity from the power grid is used to charge the batteries at night (making it a plug-in hybrid vehicle, PHEV) and a small engine is used to generate electric power on board. The battery alone can power the car for the first 40 miles of driving. When the battery is depleted, a small efficient engine takes over and runs the car while recharging. If the customer goes fewer than 40 miles per day, not unusual for American commuters, the car will require no gasoline at all! Of course the customer will pay for the engine, gas tank, and all of the services associated with this “range extender” concept even if he does not use it. GM may or many not be able to make money on the Volt, but the prospect of such a car is currently very attractive and it looks like the Volt will actually be offered, pending successful development. New battery technology has been supported by the United Stated Advanced Battery Consortium made up of auto industry, utility and government agencies, and it is possible this technology will turn up in the Volt.

As the world’s petroleum becomes ever more scarce and as more is known about global warming, the cost of operating a combustion engine car will probably rise. Eventually, the introduction of renewable electric power and further advances in battery technology can be expected to make electric cars attractive for mass markets. In the meantime, the exact development of markets is uncertain, and there will probably be many approaches tried. One this is certain, though: the electric vehicle is not going away any time soon.

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Dr. John Dunning received his Ph.D. in Engineering from UCLA in 1971. He directed electrochemical research at General Motors Research Laboratories and developed batteries, controls and test equipment for electric and hybrid vehicles for GM until he retired in 1999. He served as Chairman of the Technical Advisory Committee of the United States Advanced Battery Consortium and as Executive Director of Electricore, Inc. He is now Research Scholar in Residence at California State Polytechnic University, San Luis Obispo. He can be reached at gmwestern@aol.com.