HispanicBusiness

Automakers continue improving conventional gasoline engines to save fuel. For 2008, Chrysler offers new computer-controlled Phoenix V-6 engines that drop to three cylinders when less power is needed, increasing fuel economy as much as 8 percent.

Chevrolet calls its system Active Fuel Management; it shuts down four of the six or eight cylinders on level roads. It's offered in the Avalanche, Impala, Monte Carlo, Silverado, Suburban, Tahoe, and Trailblazer.

Diesels
Gone are the stinky smokers of the past; in come super-clean-burning diesels, especially when they burn low-sulfur fuel made with a combination of petroleum and animal fat or vegetable oil.

Modern efficient diesel engines cost more because of their construction, but they improve fuel economy up to 30 percent. They're very popular in Europe – the National Biodiesel Board estimates 40 percent of passenger vehicles sold in Europe run with diesel engines. Though they haven't caught on well with U.S. buyers, automakers keep trying. Among them, General Motors plans to produce diesel-powered Cadillac and Saturn models. Volkswagen will offer its Jetta TDI in all 50 states for 2008; the company says its "clean diesel" reduces nitrogen-oxide emissions by 90 percent and gets up to 40 percent better fuel economy than gasoline. Mercedes-Benz has introduced new Blue Tec diesel engines that it says not only offer cleaner emissions, but also boost horsepower and torque. And Chrysler plans to put a clean diesel in its 2009 Jeep Cherokee.

Fuel cells
Fuel-cell research continues moving ahead – as it has done for decades. Challenges have included the high cost of precious metals inside them that are integral to the power-producing reaction between hydrogen and oxygen; reducing them to a manageable size; and creating cells that work well in cold weather.

Chevrolet plans to collect data with its Project Driveway market test, but Honda will take its FCX into showrooms for 2008. Engineers shrunk the fuel-cell stack to the size of a briefcase and put it into the transmission hump, with hydrogen tanks below and in front of the trunk. Chrysler has been testing fuel-cell engines in Australian buses and European passenger vehicles, and General Motors has developed a fuel-cell-model Sequel that goes from 0 to 60 mph in 10 seconds and keeps going for 300 miles. Ford's fuel-cell Explorer goes 350 miles between fill-ups. Ford intends to market its fuel-cell-powered Focus FCV initially as a fleet vehicle; 30 of the cars are undergoing road tests in the United States, Canada and Germany.

Experts don't forecast big consumer sales of fuel-cell vehicles in the near future because hydrogen filling pumps will be hard to find. In fact, the National Fuel Cell Research Center, founded by the federal Department of Energy in 1998 at the University of California, Irvine, only recently opened a hydrogen fueling station to serve Toyota Highlander fleet vehicles.

Electricity
You'll be hard pressed to buy an electric car from a big automaker, though they've been available for years from small shops. Chevrolet has been showing its Volt electric concept car at shows. The idea is that it can run on electricity and just about anything else: gasoline, ethanol or biodiesel. The Volt is intended for short commutes and can carry four to five passengers.

Twenty-five years ago, the big news in passenger cars was efficient assembly, not efficient engines and cleaner alternative fuels. In 25 more years, advances in technology may make today's cars seem like old-time wind wagons. Though we may not yet fly to work, we'll surely breathe a cleaner breeze.