In Utah, where natural gas costs the equivalent of 85 cents a gallon because of a combination of local gas supplies and price regulation, enough drivers have switched that stations cannot compress gas quickly enough to meet demand. “In some cases, we are not able to give people a full fill,” said Darren Shepherd, a spokesman for Questar Gas, which operates 19 fueling stations in the state.
Honda Motor, which brought the GX to market in 1998 to satisfy demand from government fleets, has been caught off guard by the sudden interest. It is doubling its annual production to around 2,000 cars, still paltry, for the 2009 model year. Chris Martin, a company spokesman, cited “limited production capacity” and difficulty in obtaining parts like fuel tanks.
Most of the natural gas vehicles in the United States today are fleet vehicles, like taxis, buses and trucks. Other parts of the world, including Europe, Latin America and the natural gas-producing Middle East, have gone much farther in embracing natural gas vehicles. In Argentina, about a fifth of all vehicles run on the fuel.
If the United States adopted these vehicles on a large scale without decreasing its use of natural gas for other purposes, prices for the fuel would almost certainly rise. This would discomfit utilities — which rely on natural gas for slightly more than 20 percent of national power generation — and chemical companies. They are already braced to pay more for natural gas if Congress passes legislation addressing climate change, which will increase demand for clean fuels.
“We’re mindful of anything that has the potential of raising the price of natural gas,” said Steven L. Kline, a vice president at PG&E, a California utility. He added, however, that he would expect any ramp-up to be accompanied by increased supply, particularly from a yet-to-be-built natural gas pipeline in Alaska.
Reserves of natural gas may also increase because of improving technology for recovering it from unconventional fields, like shale deposits. Two large recent shale discoveries in the Eastern and Southern United States have set off a drilling frenzy.
Mr. Pickens argues that a surge in wind-generated electricity could free up natural gas for vehicles. He acknowledged, however, that natural gas played a crucial role in meeting the need for peak power, and that extra demand for natural gas in vehicles could send electricity bills higher.
In the meantime, acceptance is growing for the idea that the United States could make greater use of wind power. An Energy Department study released in May said that by 2030, the United States could get 20 percent of its electricity generation from wind, up from 1 percent today.
But a large-scale increase poses challenges. For starters, a huge investment in transmission lines would be necessary to carry the power from remote, windy areas to large cities.
Mr. Pickens is personally encountering transmission challenges as he invests in the world’s largest wind farm in the Texas Panhandle, a project costing up to $12 billion. Some landowners are upset about potential transmission lines crossing their property.
In his national plan, Mr. Pickens has pegged the cost of the wind turbines at roughly $1 trillion, not counting additional power lines. But that is wildly optimistic, contends Jamie Webster of PFC Energy, a consulting firm. To displace all generation from natural gas would require turbines costing as much as $14 trillion, he says.
Mr. Pickens “wants to paint the rosiest picture,” Mr. Webster said.
Still, Mr. Webster said that Mr. Pickens may be doing the nation a service with his advertisements.
“The end result of his plan,” Mr. Webster said, “is that it could end up influencing the presidential debates and getting a greater discussion of energy security.”