2012 Honda Civic Natural Gas (© American Honda Motor Co., Inc.)Click to enlarge picture

2012 Honda Civic Natural Gas

The battle for the best alternative fuel to petroleum has been waged, unsuccessfully, since the automobile was invented. A century and a quarter later, we still have not found a fuel as abundant, energy-rich and cost-effective as gasoline and diesel. Ethanol, hydrogen, solar, electricity, a DeLorean running on trash — none has yet proved useful for the masses. But one fuel is even more abundant than oil, burns cleaner and is incredibly cheap and relatively easy to use: natural gas.

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Compressed natural gas, or CNG, is the same gas that lights up stoves and heats homes, only instead of running through pipelines, it is stored in vehicle tanks at high pressure. (Liquefied natural gas, or LNG, is used by utility companies and tractor-trailers and for overseas shipments, so we won't cover it here.) CNG is at least 90 percent methane, a greenhouse gas found in mineral deposits, shale rock and, as you may have heard, belches from cows. But despite its heat-trapping effects — methane alone is 23 times as potent as carbon dioxide — compressed natural gas reduces overall vehicle greenhouse-gas emissions by at least 21 percent when compared with gasoline, according to the Energy Department. Particulates and carbon monoxide are also significantly cut back.

In plain dollars and political sense, natural gas wins. The United States has enough of it to last 92 years with current reserves, and at 24 trillion cubic feet of gas used per year, we are not exactly scrimping. It is also nearly free from OPEC control and the turmoil that comes from accepting foreign oil. Despite a few LNG imports from Qatar and Yemen, nearly all of the CNG the U.S. imports comes from Canada.

Natural-gas prices hit a 10-year low this spring, thanks to an unusually warm winter and increased production efficiency. At the pump, CNG prices stay constant for months at time, unlike the roller-coaster fluctuations at your local gas station. In Massachusetts, CNG costs $2.38 for the equivalent of a gallon of gasoline. In the petroleum-rich states of the Southwest and the Gulf Coast, CNG stations display 1990s prices: $1.50 or less per gallon equivalent.

"Right now, with the prices of gasoline as it compares to natural gas, we've got a situation where the economics are there," says Paul Shaffer, vice president of BAF, an aftermarket company that converts Ford vehicles to CNG. "It's technology that's available now. It's not technology of the future."

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Models, Prices, Conversions, Driving
Spurred by low fuel prices and a car industry willing to experiment — no doubt inspired by the Nissan Leaf and Chevrolet Volt — more automakers are now selling natural-gas-powered vehicles in the U.S. Roughly 130,000 such vehicles are operating here, mostly in government or private fleets such as city buses, sanitation trucks and vans. The European Union has nearly nine times that amount. The relatively low American numbers have not stopped Honda from selling the Civic Natural Gas in the U.S. since 1998, and it remains the only passenger car of its kind in America. Last year, during the Civic's ninth redesign, Honda sold just 990 CNG models.

This spring, General Motors will sell natural-gas-powered versions of the Chevrolet Silverado and GMC Sierra pickups, in addition to the Chevrolet Express and GMC Savana cargo vans. By July, Chrysler will have introduced a CNG Ram. BAF, which is a subsidiary of the natural-gas utility Clean Energy, sells natural-gas-powered versions of the Ford Econoline, F-Series and Transit Connect through regular dealers. And VPG, an upstart automaker that builds the handicapped-accessible MV-1 van, offers a natural-gas option. Aside from the Civic, these large vans and trucks are America's only natural-gas-powered vehicles.

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They are also pricey. The Civic Natural Gas is $5,650 more than a regular Civic EX and $2,105 more than the Civic Hybrid. The CNG Ram will cost $11,000 more than its gasoline counterpart, and Ford natural-gas conversions can cost as little as $10,000 or run more than $20,000 per vehicle. If you think it might be easier to convert your own car, think again. Conversion kits and companies that are not EPA-certified — a tedious, expensive process — can invite federal fines, not to mention the safety hazards of mishandling compressed gas.

Now, to the boring part. Anyone expecting a revolutionary driving experience will be disappointed by the simplicity of a natural-gas-powered vehicle. It drives and sounds exactly like any gasoline engine, but without the noxious smell during a cold start. With hardened valve seats, modified injectors and a new pressure regulator, combustion engines can burn natural gas just fine. That makes it easy to build "bi-fuel" vehicles that can run on either natural gas or gasoline, much as the Chevrolet Volt can switch between gasoline and electricity. No fancy transmissions, heavy batteries or complicated hybrid systems are needed. As such, fuel economy is not significantly affected.

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