"We now have cars that are more fuel efficient, bigger, and faster," Berman said. "[Hybrid technology] provides a set of controls for automakers to dial up or dial down any of those features. The catch is that it's hard to dial them all up at the same time."
Some industry analysts see the shift as necessary to the rise of hybrids as more mainstream vehicles.
"Are some of the new models as parsimonious at the pump as the Prius? Of course not, but you're certainly better off than with a [conventional] vehicle that would give you comparable oomph," said Jon Coifman, spokesperson for the National Resources Defense Council in New York City.
"In the grand scheme it's going to be important that drivers don't automatically associate hybrids with sacrifice," he continued. "People want a little fun behind the wheel, and hybrids shouldn't be perceived as a hair shirt."
But for those who lament the fuel economy of some models, HybridCars.com's Berman says the next few years will only get more interesting.
Hybrid technology isn't one size fits all. Different models will offer an increasingly diverse suite of benefits.
"GM [which currently has no hybrid offerings] will enter the market with their ultramild hybrids," he said. "The first is the Saturn VUE SUV, which is basically not a full hybrid but a very inexpensive way to get about 10 percent more out of your fuel economy [for a price increase of a few hundred U.S. dollars]. Some people don't even call it a hybrid."
The growing number of choices and amenities may help the vehicles move into markets beyond mileage-driven early adopters.
"For the individual consumer, the comparison is to what they are driving now, the total bundle of features," Berman said. "There's a segment of the market that is perfectly ecstatic about having a car that's faster and a little bit more fuel efficient," he said. "From what I gather from e-mails and our discussion boards, people are happily trading cars that get 13 miles a gallon (5.5 kilometers a liter) for cars that get 25 miles a gallon (10.6 kilometers a liter)."
Even so-called full hybridswhich can travel on electricity alone part of the timecan be tuned for either far greater fuel efficiency or for higher power.
Automakers currently seem to be leaning toward horsepower. But someday such choices could go the other way or even be left up to individual drivers.
"We have a vision of the driver being able to hook up their laptop to a port to alter that profile and get the driving characteristics that they want," said Cindy Knight, spokesperson for Toyota in Torrance, California. "That's an idea for the future. Right now it takes a horde of technicians to do that."
Rosy Outlook for Green Hybrid Vehicles?
Soaring gasoline prices could mean a promising future for the hybrid market, and Toyota's hybrid models are already back-ordered. Yet hybrids account for only 1 percent of the U.S. automobile market, and no one is sure how mainstream acceptance of the vehicles may develop.
Some are more bullish than others.
Toyota president Katsuaki Watanabe has announced his hope to sell a million hybrids per year by early next decade. "At our current rate, that's about 600,000 hybrids in the United States," Toyota Motor Sales USA president Jim Press told last week's auto industry conference in Traverse City, Michigan.
Toyota officials said that, to reach that goal, some 25 percent of the company's vehicles would have to be hybrids. They added that ten new models are currently under development.
Some analysts believe that hybrid demand will tail off because only a fixed number of consumers will be willing to pay the $3,000 to $5,000 price premium the vehicles carry compared to similar conventional models.
Competition from more efficient diesels and conventional vehicles could also challenge hybrid growth, but some help is available courtesy of the U.S. Internal Revenue Service.
Currently, hybrid buyers are eligible for a federal tax deduction under the IRS's Clean Fuels program. Under a new U.S. energy bill signed into law by President George W. Bush today, they would be eligible for more valuable tax credits.
The bill promotes hybrid technology rather than fuel efficiency, so hybrid buyers could actually enjoy breaks at the expense of buyers who choose more efficient nonhybrid vehicles. The traditionally powered Toyota Corolla, for instance, gets better gas mileage than the Honda Accord Hybrid.
The new law also caps tax incentives at 60,000 vehicles per automaker before a year-2010 cutoff, which could curb the total numbers of hybrids sold. HybridCars.com reports that Toyota sold nearly 15,000 hybrids during July alone.
Still, most observers seemed to welcome any hybrid help from the U.S. government.
"We think it's a validation of hybrid technology," Toyota's Knight said. "The government is saying that they support itand that's saying a lot."
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