Article at a glance:

Tomorrow's cars, today's engines

The internal-combustion engine has been synonymous with the automobile throughout the 20th century. Now it faces a rival from the past, the hybrid-electric engine, and a brand-new adversary, the fuel cell. Even so, while these technologies have been getting all the hype, and not a little funding, the internal-combustion engine has been pressing ahead quietly but effectively in dimensions such as power, fuel efficiency, and emissions reductions. But regulation remains its Achilles heel as concerns over greenhouse gas emissions and national energy independence play out.

The take-away

Cars powered by the fuel cell may be in mass production by 2010, and the fuel cell may well be the leading automotive technology of the late 21st century. But the internal-combustion engine should power most new vehicles for at least the next 25 years and most vehicles on the road for a lot longer.