Amid all the hoopla over developing clean, sustainable alternatives to oil and coal to fuel the nation's vehicles and power plants, one that tends to get overlooked by many is natural gas.
Granted, natural gas is a fossil fuel that doesn't qualify as a renewable source of energy like solar, wind, hydrogen fuel cells, or even cellulosic ethanol. But the vast reserves that have been identified in U.S. shale formations in recent years along with new drilling techniques make it a plentiful source of fuel for just about every domestic use for hundreds of years to come. Moreover, it comes at a much lower price than most renewables and burns much cleaner as well as less expensively than other fossil fuels.
In a vehicle engine, greenhouse gas emissions are cut by nearly half compared to gasoline or diesel fuel, and other air pollutants are cut by even more. Yet the price at the pump for natural gas has remained stable at less than $1.50 per gasoline gallon equivalent (GGE) even as the price of gas has spiked to $4. And placing reliance on a stable domestic source of fuel removes the risk of dependence on foreign oil, whose unstable sources of supply could cause much higher spikes.
The trouble is that outside of California and the petroleum patch in the Southwest, there are very few pumps in the U.S. where the compressed natural gas needed to fuel a vehicle can be obtained. And this dearth of fueling stations is part of a chick-and-egg problem that's kept automakers from producing natural gas vehicles (NGVs).
The only NGV passenger car on the road in the U.S. today is the Honda Civic GX, which for eight years in a row has been named the "Greenest Vehicle" by the American Council for an Energy Efficient Economy. Yet only about 1,000 of these cars with a sticker price of about $25,000 were sold last year.
In Knoxville, there's not a single public fueling station to be found. Nor is there a local distributor for a product known as Phill, which is the one brand of residential CNG pump on the market that can be installed much like a water heater but costs more than $4,000.
The East Tennessee Clean Fuels Coalition is partnering with an entrepreneur, Robert Patterson of PBG Energy, in seeking a federal grant to help fill this void. Patterson envisions locating three multi-pump CNG stations in Knoxville at a total cost of about $1.5 million. The initial emphasis is on fueling fleets of trucks and cargo or service vans rather than passenger vehicles. "That's where the sweet spot is," says Patterson, with Navistar now offering several CNG truck models and General Motors its Chevrolet Express/GMC Savana van.
While a federal tax credit of up to $30,000 per station is also available, government support for CNG infrastructure pales by comparison with the largesse bestowed upon the rollout of the much more heralded class of "clean" cars coming on the road: namely, electric vehicles (EVs). The Department of Energy has awarded $115 million in grants to a San Francisco-based firm, ECOtality, for deployment of 15,000 EV charging stations in just six states. Thanks to its being the home of the Nissan Leaf, Tennessee is one of them, and 350 public charging stations are projected in the Knoxville area alone. (So far, only 15 locations within the city have been announced.)
Similarly, buyers of the Leaf and the Chevy Volt also qualify for federal tax credits of up to $7,500 against the purchase price ($32,750 before the credit for a Leaf, currently) whereas a lesser tax credit for NGV purchases expired at the end of last year.
So why are EVs being shown so much favoritism compared to NGVs? The executive director of the Clean Fuels Coalition, Jonathan Overly, can only venture, "In my 10 years at this job, I've seen different alternative fuels in the spotlight, and then ebb and flow.... EVs just happened to be the darling when the ARRA funding [i.e., massive federal stimulus outlays] came out in 2009."
It's true that EVs could be classified as emission free (until fuel that's burned to generate the electricity they consume is taken into account) whereas NGVs only reduce pollutants compared to gasoline. But any EV advantage on this account is offset in my mind by the greater driving convenience of an NGV. Even though the Honda Civic GX's fuel tank will only hold eight GGEs, at 30-plus miles to the gallon that gives it 250 miles of driving range—five times that of a Nissan Leaf. In my own case, that's the difference between having to refuel once a week versus nearly daily (or all night on a home charger).
The only other thing to be said against natural gas is the controversial way in which it's being extracted from the shale formations that hold the nation's enormous reserves. The extraction process, colloquially known as fracking, involves pumping millions of gallons of water laced with toxic chemicals and sand into the formations to release the natural gas. Because all of this is taking place several thousand feet beneath the earth's surface, there's no evidence of contamination of water tables, which aren't anywhere near that deep. But there have been instances in which fluids flowing back up to the Earth's surface with the gas have polluted nearby ground water. The industry, of course, insists that proper safety precautions can prevent this.
That being said, the electric power industry is doing a lot more than the transportation sector to move toward natural gas plants with much lower emissions than the coal plants that have been its mainstay. The only new TVA generating facility to come on line in the past decade is a 550 megawatt natural-gas plant in Brownsville. And TVA is nearing completion of an 880 megawatt natural-gas facility in Rogersville, as well as acquiring a 968 megawatt plant in Mississippi. Together with the 1,150 megawatt Watts Bar II nuclear plant that's due for completion in 2013, they will replace the 2,700 megawatts of generating capacity at 18 coal-fueled units that are due be shut down by 2017.
Beyond that, TVA's vice president for fossil generation, Tim Hope, says, "There's no question we will be adding additional natural-gas facilities" as part of a master plan for increasing capacity by 2020. "With natural gas in the $3 to $4 range [per 1,000 cubic feet], it's very price competitive," Hope says. And in an allusion to TVA's calamitous 2008 coal-ash spill in Kingston, he wryly adds that, "There is no coal ash."