Natural gas vehicles
' Dedicated: Designed to run only on natural gas. ' Bi-fuel: Two separate fueling systems that enable them to run on either natural gas or gasoline. ' Dual-fuel: Traditionally limited to heavy-duty applications, have fuel systems that run on natural gas, and use diesel fuel for ignition assistance. Source: U.S. Department of Energy
About natural gas
' To provide adequate driving range, compressed natural gas is stored in cylinders at a pressure of 3,000 to 3,600 pounds per square inch. ' A CNG-powered vehicle gets about the same fuel economy as a conventional gasoline vehicle on a gasoline gallon equivalent basis. ' A GGE equals about 5.66 pounds of CNG. CNG is used in light-, medium- and heavy-duty applications. ' Liquefied natural gas is produced by purifying natural gas and super-cooling it to -260 degrees F to turn it into a liquid. ' Because it must be kept at cold temperatures, LNG is stored in double-walled, vacuum-insulated pressure vessels. ' LNG is good for trucks needing a longer range because liquid is more dense than CNG, allowing more energy to be stored by volume in a given tank. ' LNG is typically used in medium- and heavy duty vehicles. Source: U.S. Department of Energy
Owen Maclellan says his grandfather tells him stories of having to bring an extra shirt to work so he could change during the day because the air pollution in Chattanooga was so bad.
Maclellan's company has worked with locally based Teems Electric to open what's billed as the first public fueling station of environmentally clean compressed natural gas in metropolitan Chattanooga.
The Fuel-A-New station has opened in Ringgold, Ga., at 465 Rollins Industrial Court, and it's just one of three or four such public CNG sites which may pop up in the Scenic City over the next year or so as the alternative fuel gains more traction, officials said.
Another $2 million CNG refueling site is scheduled to open this summer along Interstate 75 in Dalton, Ga.
"Different alternative fuels have grown. CNG has growth potential stronger than any of them," said Jonathan Overly, who heads the East Tennessee Clean Fuels Coalition.
Maclellan, vice president of Chattanooga-based Mach Fuels Inc., said the expectation is that the new Ringgold station will attract trucking companies, fleet users and others.
"A lot of large tractor trailer companies throughout the U.S., they do a lot of research to plan out their routes," said Maclellan, whose company helps convert vehicles to CNG and provides support to entities such as Teems to build fueling stations.
Miles Teems, president of Teems Electric, said the new station represents a $700,000 investment, and he's looking at building another nearby off Battlefield Parkway.
The electrical contractor has about 50 trucks in its fleet and up to 30 are expected to be converted to CNG use by the end of this summer, he said.
"There was no place to buy it around here," Teems said. "For me to change my fleet to CNG, I had to make a decision to build a station to fill up.
"We looked at our fuel bill. The savings we could get from that alone was motivation enough to look at it," Teems said.
Overly said that while people like to be environmentally conscious, "the almighty dollar rules the world. Everybody wants to be green but cost-saving is the bottom line."
According to the U.S. Department of Energy, natural gas powers about 150,000 vehicles in the United States and roughly 15.2 million vehicles worldwide.
Natural gas vehicles which can run on compressed natural gas are seen as good choices for high-mileage, centrally fueled fleets that operate within a limited area, DOE said. For vehicles needing to travel long distances, liquified natural gas is seen as a good choice, it said.
Advantages of natural gas as a transportation fuel include its domestic availability, distribution infrastructure, low cost and inherently clean-burning qualities, the agency said.
Ford Motor Co. has said its 2016 F-150 pickup will be available with a 5.0-liter V8 engine that can run on compressed natural gas or propane, according to Forbes. It's part of a growing lineup of CNG vehicles from the Dearborn, Mich.-based automaker.
Ford's commercial vehicle customers have been asking for more trucks and vans that can run on compressed natural gas because it lowers their fleet operating costs and reduces greenhouse gas emissions, Forbes said.
The DOE estimates there are about 830 CNG stations nationally, excluding private facilities.
Maclellan said there are a handful of private stations locally, noting Mach Fuels has one.
CNG stations nationally are more common in areas that are in nonattainment of U.S. air quality standards. But, he noted, Chattanooga also has had its share of air-quality problems.
"We started educating people on CNG infrastructure three years ago," Maclellan said. "You need fueling stations first before you can promote the vehicles."
Maclellan met Teems at a business association meeting, and they started to work together, with Mach Fuels providing consulting and a lot of the installation work.
Athens, Tenn., already has a public station in Southeast Tennessee.
A partnership between two compressed natural gas suppliers for trucks known as amp Trillium LLC is building new CNG refueling stations this summer in Dalton, Ga., and Newport, Tenn. Steve Josephs, the co-founder and director of engineering for amp Trillium, said the company is eager to add an outlet in Chattanooga to meet what he projects will be a 20 to 30 percent annual growth in CNG fueling stations nationwide. Josephs' firm already operates 19 stations around the country targeted at CNG-powered trucks.
In five to 10 years, Maclellan said, he foresees home refueling equipment that taps into natural gas.
"I see that really catching on," he said.
Teems said that CNG is a lot more clean burning than diesel fuel, for example. Also, he said, most of the CNG used in the U.S. is produced domestically.
"It helps [against] foreign dependency," Teems said.
Overly, whose group last month held a series of rallies in the state in support of CNG use, said he's hopeful Chattanooga has a spot on a similar tour next year.
He said the natural gas industry is aggressively cross promoting use of the fuel and letting people know how they can invest.
Contact Mike Pare at mpare@timesfreepress.com or 423-757-6318.
A semi truck is refueled at the amp CNG plant in Waco, Texas. The station is similar to what will be built this summer in Dalton, Ga.