Natural gas hits resistance as fuel of clean-air future

Natural gas has been favored by federal and local governments as a way to reduce air pollution from buses and trains and to generate electricity, but the fuel has become a boondoggle for many public transportation companies.

"If they had consulted anyone other than politicians, they would have known that," said Sterling Burnett, senior fellow with the National Center for Policy Analysis. "And it wasn't just transportation. A few years ago, people were saying natural gas was going to be our electricity and fuel for cars and everything else."

President Clinton made the first push in the mid-1990s and Congress followed suit by granting wide-ranging incentives to use natural gas as an energy source.

President Bush went on to increase funding to develop natural gas technology, and many cities began using the fuel for public transportation.

The shift proved costly for some public transportation companies, but relief may be on the way in this year's version of the energy bill. An amendment introduced by Sen. George V. Voinovich, Ohio Republican, would create incentives to use clean diesel and biodiesel fuels made from soybeans.

"They did what they thought was responsible and our bill basically is a voluntary program with incentive programs for states to get involved in retrofitting these engines and, to be honest, it is the transportation companies that have already started on it," Mr. Voinovich said.

He said the hope is to leverage public-private funding to retrofit old diesel engines for cleaner fuels and to develop fuel technologies.

Transportation companies began looking at clean diesel after discovering how difficult it is to harness natural gas.

Natural gas reduces nitrous oxide and other hydrocarbon emissions, but its efficiency depends on how the energy is harnessed.

"The buses are giving great reliability and we are having great success with them," said Lisa Farbstein, spokeswoman for the Washington Metropolitan Area Transit Authority, which uses compressed natural gas engines.

She said the price-per-gallon equivalent for compressed natural gas is about $1.43, compared with $1.80 to $1.90 for diesel.

Bus operations using supercooled liquid natural gas have found problems with the fuel.

"Our experience with LNG from a reliability standpoint, we have now made them comparable to our diesel fleet, but that was not how it started out in the mid-1990s when we started," said Mike Hubbell, vice president of maintenance for Dallas Area Rapid Transit.

He said Dallas now is concerned about the fuel costs.

"But now with the development of ultra-low-sulfur diesel, it allows us to use diesel buses that are as clean or cleaner than natural gas," Mr. Hubbell said.