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The Loma Prietan
August/September 1999EV's Aren't Just for Cruising Anymore
by Richard Zimmerman
The electric car sales specialist asked me to wait until she moved the General Motors EV-1 to the front of the dealership so I could test drive it. I heard a click as she turned it on and then the car moved away from me in a ghostly silence.
EVs are so quiet, Gene Waddell, Sunnyvale Fleet Manager says, that City of Sunnyvale employees who drive EVs undergo training to make sure they are alert to the fact that pedestrians won't hear them coming.
But quiet operation isn't the best or only reason for driving an electric car. The California Air Resources Board (ARB) regulations stipulate that, by 2003, 10% of the new vehicles sold in California must be zero emission level vehicles (ZEV). The problem, according to the ARB, is that 95% of Californians still live in areas that do not meet Federal and State healthy air standards even though current cars sold in California are 98% cleaner than they were 20 years ago.
Battery powered EVs are the only technology that meets the ZEV requirement. EVs have zero local emissions of pollutants such as ozone, carbon monoxide and nitrogen oxides. Even when power plant pollution is factored in, EVs have less than 10% of the smog contribution of the average vehicle in California according to the ARB.
EVs also reduce the emission of carbon dioxide, the primary greenhouse gas. "Cars produce from 20 to 25% of the greenhouse gas emissions in the world," says Mark Hertsgaard, author of "Earth Odyssey."
Unlike the internal combustion engine where energy conversion takes place in the car, the primary energy conversion for the EV takes place at the electrical power generation plants.
Power generation does not come at a zero cost to the environment, however. Hertsgaard says that "electric power plants produce another 25% of the greenhouse gases worldwide." However, California is making strides in cleaning up electrical power generation. In 1997, renewable sources and hydroelectric generation accounted for 32% of the sources of energy in California according to the California Energy Commission. Unfortunately, nuclear energy and coal generated 28% of our electricity. Gas was the leading producer with 35%, and oil accounted for less than 0.1%. These numbers include imports from outside the state which account for about 20% of our electricity.
This contrasts favorably with the U.S. as a whole where coal accounts for 55% of the energy source for electricity. The power generation plant emissions can, the ARB says, can be controlled much easier than the emissions from millions of cars.
Thus the obvious advantages of the EV are: less pollution and less oil usage. Tune ups and oil changes are ancient history. And, of course, you can forget about the cost of gasoline. But what about the suitability of the cars?
Range?
The EV-1 I drove has a practical range of less than 70 miles according to GM. In fact, the range indicator when I drove the car, with a fully charged battery, indicated an expected range of less than 30 miles. This predicted range comes about because the calculation is based on the driving styles of the people who have driven the car. Almost everyone test driving punches the accelerator to see just what the car will do, draining the battery quicker than "normal" usage would.
The actual range of the car would depend upon the conditions and driving style of the operator. For example, the car has an increased range when outside temperatures are warmer.
But David Coales, project leader for the Bay Area Action EV project, says range is a perceived problem, not a real one. "Most trips are short ones," he says.
Executive committee member. Kelly Moran, who leases a Honda EVplus for use as her primary car, agrees. "Range is not an issue," she says. "On a typical day I put as many as 50 miles on the car." So far she has yet to get the car into "limp mode", a mode where a governor limits speed to save energy that occurs when the batteries are approximately 90% discharged. Moran says her longest single trip was around 90 miles. Waddell said that their Toyota RAV4-EV "has a honest range of 100 miles."
Batteries
One reason for the increased range of the Toyota and Honda EVs is that they use nickel-metal-hydride (NMH) batteries. The EV-1 currently uses lead-acid batteries that are similar to the one in your gasoline powered car. Lead-acid batteries have about half the energy stored per pound of weight of the newer NMH technology.
The expensive experimental NMH batteries represent something of an unknown for manufacturers, however. "NMH Batteries are seven times more costly than lead-acid batteries," says Stan Skokan, President of Electric Vehicles, Inc.
The Honda EVPlus and the EV-1 are only available under three-year leasing arrangements due to the unknowable future performance of the batteries.
One of the more promising technologies is the fuel-cell. A fuel-cell combines oxygen and hydrogen, making water, and giving off electrical energy as a by-product. In use in the space program since the 1960s (think Apollo 13) fuel-cells are expensive and large.
Here on earth, the required oxygen can be taken out of the air while the hydrogen, the most plentiful element on earth, is available from hydrocarbons or can be carried in liquid or gaseous form on the car.
DaimlerChrysler's NECAR-4 represents the forefront of fuel-cell technology for automobiles. According to the company, the NECAR-4 has a range of 280 miles and a top speed of around 90 mph. But the real advantage of their fuel-cell is that they have reduced the size to the point that it fits in a "A-Class" Mercedes, a small car. Until recently, fuel-cells required van-sized trucks to carry the hardware. Cost remains an issue.
Ford and DaimlerChrysler each recently announced a program to put as many as 15 fuel-cell vehicles on the road in California next year. These buses are the first step toward making fuel-cell technology available. Both companies indicate that they expect to begin mass production of fuel-cell powered cars by 2004.
Compromise?
Even though we make more short trips than long ones, most still want to take the longer trip from time to time. EVs don't fill that niche yet.
Manufacturers are about to offer hybrid electric vehicles to the public. These cars have both battery powered and combustion engine operation. The controller decides which mode to use and switches back and forth automatically. Charging of the energy storage device-usually a battery-takes place internally so no charging station is required.
The advantage of these cars is increased range over the pure EV. The Toyota Prius, to be introduced in the US in 2000 and already being sold in Japan, has a range of about 750 miles. In Japan it gets around 66 miles per gallon. Toyota marketing says U.S. mileage will be less since U.S. driving styles differ.
The disadvantage of the hybrid cars is that they are not zero emissions vehicles. It would appear that they may be a crossover technology, holding market share until the true EV is ready.
Not a congestion solution
Neither EVs or hybrids solve the more vexing problem of congestion. "Public transportation must be better and more accessible," says Coale. "EVs should be used for short trips where they are well suited for the task." Even if we all drove EVs tomorrow, the congestion would remain the same.
Learn more
Jane Holtz Kay, Asphalt Nation, Crown Publishers, 1997
Robert Q. Riley "Alternative Cars in the 21st Century." Society of Automotive Engineers, Inc. 1994
Scott A. Cronk "Building the E-Motive Industry", Society of Automotive Engineers, Inc. 1995
Air Resource Board Zero-Emission Vehicle Program