Natural-gas vehicles like the Honda Civic CNG have been pushed from the limelight (and off dealer lots) by hybrids and electric vehicles in the name of fuel efficiency, as the supposed answer to ending U.S. dependence on foreign oil.

As the founder of a successful Oklahoma-based natural-gas firm and pioneer of ultradeep natural-gas exploration, Robert A. Hefner III has good reason to push natural gas as an alternative to imported oil. And 30 years after testifying before Congress about substantial supplies of domestic natural gas, Hefner persists in promoting natural gas as a practical alternative to oil, as well as coal and nuclear power.

Hefner continues his crusade in a new documentary titled "The Grand Energy Transition: Natural Gas – The Bridge Fuel to Our Sustainable Future," based on his book of the same name. The film will premiere in Washington, D.C., next week. According to a press release, the film claims natural gas can power all -- yes, all -- cars and trucks in the U.S. to reduce the country's dependence on foreign oil.

We haven't seen the film, but have to wonder whether it will address the infrastructure issue -- or lack of it -- to make CNG refueling easy for everyday drivers.

In making a case for the clean energy that natural gas provides, the film will show footage from the oil fields of the Anadarko Basin in Texas and Oklahoma as well as scenes from the the nuclear disaster at Chernobyl and a coal-slurry spill in Tennessee. While we agree that oil is dirty and that dependence on it puts the U.S. in a precarious place politically, natural-gas drilling and production has its own dangers.

Plus, many more people are rushing out to buy the latest Toyota Prius than the Honda CNG -- or plug-in electric competitors.