基础设施是电动车发展的最大挑战

Auto experts say electric vehicles are a practical alternative to gasoline-powered cars, at least for some drivers.  The biggest challenge for the auto industry is expanding the infrastructure for recharging the vehicles.

With last year's release of the Chevy Volt and the Nissan Leaf, some say the day of the electric vehicle has arrived.   The Volt uses a rechargeable battery, and for additional range, can switch to a small gasoline engine to recharge the battery.  The Leaf is an all-electric vehicle that is designed for short commutes.

But electric cars have been around a long time.  They have been available to compete with gasoline-powered vehicles for decades, and were once a significant part of the market.

One that looks like a horse-drawn buggy is on display at the Petersen Automotive Museum in Los Angeles.  It was built in Los Angeles by a high school student, Earle Anthony, in 1897.  Many other electric cars were on American roads in the early 20th century.   But gasoline-powered autos had a greater range and came to dominate.

In 1996, General Motors released the limited-production electric EV-1 to wide acclaim, and curator Leslie Kendall of the Petersen Museum says drivers liked it.

"And it looked cool, no doubt about it," said Kendall.  "And in the major American markets that it was tested, people got to see it and really responded favorably.  And it performed beautifully."

But the EV-1 was expensive to produce and had a limited range. The last model was produced in 1999.

Today's electric vehicles have solved some of the earlier problems, but Edward Kjaer of Southern California Edison, an electric utility company, says charging stations are hard to find outside of major cities like Los Angeles.

"There is no question that we need to focus on the distribution level, so that's really the last 50 feet of the energy delivery system, because we're going to see geographic concentrations of these vehicles," said Kjaer.

New charging stations are being installed in some businesses and at the homes of many electric vehicle owners.   The company AeroVironment has partnered with Nissan to install chargers for its all-electric Leaf, using a system compatible with other electric vehicles under a new North America standard.  AeroVironment's Kristen Helsel says the technology is spreading.

"Everywhere from Australia to Europe, Canada, Brazil, across the Pacific Rim, there's almost nowhere we're not going - India, places like that," said Helsel.  "You know, those are all places that have a really strong interest in vehicle electrification."

Electric-gasoline hybrid cars, including Toyota's Prius, are popular with drivers who are concerned with environmental pollution and rising gasoline costs.  But hybrids are a small part of the market, says analyst Karl Bauer of the automotive research firm Edmunds.com.

"The traditional gasoline engines, of course, are still what power most vehicles, so of course they make up most of the research that people do," said Bauer.  "The hybrid market has remained somewhere between two and three percent, really, for the last five-plus years, so it's still a very small amount.  And of course the pure electric market is much smaller than that."

The biggest problem is limited range.  Nissan says its all-electric Leaf can travel 160 kilometers on a single charge in city driving.  The Chevy Volt, which can switch to gasoline, can go much farther.  Bauer says batteries are improving and other ideas have been suggested to extend the range of the vehicles.

"There are a couple of different approaches, whether it's utilizing batteries that swap out quickly and you go to a corner charging station and instead of waiting an hour or five hours to charge the car, you spend five minutes, 10 minutes, having the batteries swapped out," Bauer explained.  "That's one thing they've talked about as a future solution."

Other technologies, including non-polluting hydrogen fuel cells, are also being tested by the major automakers to power the electric drive trains of new vehicles.

Electric cars may one day meet the needs of consumers faced with rising fuel costs, says the Petersen Museum's Leslie Kendall.

"They seem to want a vehicle that's powered by a renewable resource, a vehicle that does not pollute the air, a vehicle with fewer moving parts that's simpler to operate and run, a vehicle that's quieter and smoother and all those good things," noted Kendall.

With expanding infrastructure, he says electric vehicles may look more and more attractive.