Greening your ride

The forecast for "green" cars is a steady flow of hybrids,
followed by a deluge of plug-in hybrids and all-electric
vehicles. There will also be isolated pockets of
hydrogen-powered cars.

But if you expect your car-buying choices to match the volume of headlines on eco-minded car designs, you'll be disappointed.

The fact is there are not a lot of full-featured cars available today that will catapult your mileage over 100 miles per gallon. You could put an order in for a $100,000 all-electric Tesla Roadster, which is now being produced, but that's out of reach for most folks.

In two or three years, however, your options expand significantly. There is a lot of activity from incumbent car companies and start-ups to meet consumers' desire for alternatives to the centuries-old internal combustion engine.

How quickly you can get your hands on a plug-in hybrid or other technological marvel will depend on your pocketbook, the speed of engineering advances, and whether policies are put in place that will be incentives to produce cleaner cars.

Today
If you want a more efficient car to help you save money and help the atmosphere right now, think small and think hybrids.

Kelley Blue Book recently released its picks for "green cars," which has what you'd expect: hybrids and sedans with good mileage. The Environmental Protection Agency also has a green vehicle guide.

There are numerous hybrids already available and more on the way.

You can also retrofit your Toyota Prius with a larger battery, giving you a plug-in hybrid for an additional $11,000 or so. In its tests, Google has found plug-in hybrids get about 68 miles per gallon.

Also available are what are known as neighborhood electric vehicles or town cars, typically two-seaters that run entirely off batteries.

Zenn Motor, for example, sells a "zero-emission" vehicle that has a top speed of 25 miles per hour and a range up to 50 miles with the larger battery option. The Zenn costs about $16,000 and is road-legal in 44 states. A highway-capable edition, called the cityZenn, which can charge much faster, is also in the works.

Think Global, a Norwegian company that's making a car based on what was originally a Ford design, said it will bring its Think City to the U.S. next year. It can go 65 miles per hour at top speed and 110 miles on a single charge.

Another option today is a flex-fuel vehicle, which can run on gasoline or E85, a mixture of gas and 85 percent ethanol. Lack of fuel distribution is a barrier: there are currently only about 1,700 E85 pumps available, mostly in the Midwest, about 1 percent of the total.

Ethanol can be made domestically but the environmental benefits of biofuels are not clear cut.

Studies have found that corn-based ethanol has roughly the same carbon emissions as gasoline when the production-to-tailpipe lifecycle is considered. Researchers are also studying whether burning ethanol produces more smog than gas does.

Cellulosic ethanol made from agricultural residue or even trash should improve the carbon emissions. Producers hope it will be made at a commercial scale starting in a few years.

People tout biodiesel, a blend of petroleum and plant or animal fat-derived diesel, as a renewable energy source like ethanol. A whole subculture around converting diesels to "grease cars" has emerged.

According to the EPA, biodiesel can reduce carbon emissions and particulates but potentially raise smog-causing nitric oxide.

Concerns over deforestation to meet biodiesel demand over the past year have complicated the picture, making it hard to be precise about the environmental implications, which are still being studied.

In two to three years
Biofuels will play a bigger role in the fuels mix, but how much will depend on whether they can be produced sustainably in terms of land and water use, say experts.

Meanwhile, electrifying the transportation industry is a big trend that appears to have a groundswell of consumer interest.

Days after General Motors announced plans to produce the Chevy Volt plug-in hybrid, a group of enthusiasts set up the GM-Volt.com Web site. It says it has a waiting list of 37,000 people from 50 states and 64 countries for the car.

The Chevy Volt, scheduled for delivery in late 2010, will be able to go 40 miles on batteries after an overnight charge. For longer trips, an internal combustion engine will charge the battery, a set-up that's called a serial hybrid.

GM expects that most consumers will only need to use the gasoline engine for long trips and that they will spend 80 cents a day to power their Volts.

Toyota earlier this year said that it, too, will a make a plug-in hybrid in 2010. The catch is that it will only be available for fleet testing at first; cars available to consumers, which would use different batteries, are expected to come later. It also plans to make hybrids available on all its models by 2020, according to published reports.

Also in the plug-in hybrid race is Nissan, which has promised cars for fleet operators in 2010 and to retail outlets by 2012.

California utility Pacific Gas & Electric said that it will test Mitsubishi's iMeEV compact electric car for use as a fleet vehicle. BMW, too, said that it will make limited numbers of an electric Mini.

The barrier to these plug-in hybrid vehicles is not just technology but the premium that consumers are willing to pay for the better mileage, notes John Heywood, a mechanical engineering professor at the Massachusetts Institute of Technology and expert on transportation.

Using electricity in transportation "has a lot of drivers pushing it in the right direction. Now it's going to depend on how quickly can we pull down the battery costs," Heywood said. "There's a good shot at making these sensible, total economic packages but it's not guaranteed."

The future
All the activity in electrifying transportation is laying the groundwork for more choice.

Tesla Motors, for example, plans to make a high-end sedan as its second model. Its competitor, Fisker Automotive, will have a plug-in hybrid sports car at the end of 2009. Five years later, it expects to make a $40,000 sedan using the same technology.

Electric cars are not a cure-all for environmental problems, though. After all, the great majority of electricity in the U.S. comes from burning fossil fuels. But initial tests show that plug-in hybrids can reduce pollution significantly.

Wide-scale use of electric cars could have a serious downside--crashing the grid. One researcher estimated that the U.S. would have to build 160 new power plants to accommodate 25 percent plug-in hybrid penetration by 2020.

The response to that concern is what's called smart charging, or timing the flow of electricity from socket to car so that it happens in times of low demand, like the middle of the night.

Also, researchers and utilities are looking at whether the battery storage in cars can feed the electricity grid during peak demand times, called vehicle-to-grid.

Imagine that the utility would pay for the electricity stored in your car to avoid firing up an auxiliary power plant on a hot summer day. Or your car battery could be your back-up power source at home.

There's also room for business model innovation, like Project Better Place, which has signed contracts with the governments of Israel and Denmark to set up a series of stations to exchange depleted batteries for electric cars.

Given the strong demand and apparent benefits, wider use of plug-ins seems inevitable 10 years from now.

The wild card is hydrogen cars that emit water vapor from tailpipes.

Hydrogen, long promised as the fuel of the future, faces a number of serious obstacles, notably the lack of distribution and storage limitations. There are currently 16 hydrogen filling stations in the U.S.

In 10 years, though, hundreds of thousands of consumers will be driving hydrogen cars, predicted Roberto Cordaro, the CEO of Nuvera Fuel Cells. It will happen in pockets, in metropolitan areas where fuel distributors are willing to build hydrogen filling stations.

Already hundreds of people can lease fuel cell vehicles from automakers. Whether those vehicles take off and whether hydrogen is produced in an environmentally friendly way will ride on technology breakthroughs and consumer demand.

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