GAS TECHNOLOGY: CNG fueling for heavy-duty trucks

The U.S. EPA has issued rule modifications to make the conversion of gasoline and diesel engines to natural gas less restrictive and easier to achieve from engine family to engine family, and from year to year. Several federal bills are pending to add tax credits for bi-fuel (gasoline/CNG) and dual-fuel (diesel-natural gas) and to double the tax credits for CNG and LNG fueling structures.

July 20, 2010

Growing numbers of companies have figured it out: Trucks, even heavy trucks, are excellent candidates for compressed natural gas (CNG) fueling, and the technology for these vehicles is available. Until recently, it was argued that although CNG trucks make good sense, in North America, there isn’t the infrastructure to support the change. Rich Kolodziej says that’s no longer true.

Kolodziej is the president of Natural Gas Vehicles for America (NGVA). He explains that the future looks bright for natural gas-powered truck transportation. “First of all, we now have the engines and vehicles available,” Kolodziej says. “Secondly, fleet operators increasingly understand that natural gas prices are stable, and diesel prices will continue to rise. They are moving toward a natural gas future.”

Kolodziej explains that fuel costs are a major expense for trucking companies and other truck operators. Current EPA restrictions on diesel truck emissions are going to continue to tighten, making diesel fuel increasingly expensive. Kolodziej expects the major fuel cost advantage currently enjoyed by CNG to continue to broaden.

An Expanding Fueling Network

According to Leo Thomason, Executive Director of the Natural Gas Vehicle Institute, an improved CNG fueling situation is also part of the change. “The CNG fueling infrastructure has been steadily expanding beyond California over the past several years.” Thomason gives credit for much of this expansion to Clean Energy of Seal Beach, California. This organization is the largest retailer of natural gas as a transportation fuel in the United States. It has built and operates public access CNG fueling stations in Arizona, Colorado, Nevada, New Mexico, New York, Texas, Wyoming, Oklahoma and Georgia.

California has been a pioneer in the use of CNG for heavy trucks. The State and the South Coast Air Quality Management District (SCAQMD) use vehicle emission restrictions, tax incentives, and fleet fuel restrictions to encourage use of alternative fuels. Operators of fleets of more than 15 transit buses, school buses, public and private refuse trucks, street sweepers and other heavy vehicles  are required to specify alternative fuels when replacing vehicles. In most cases, these operators have chosen CNG as the alternative fuel of choice.

CNG Trucks as Cash Generators

The financial picture of CNG heavy-duty truck is encouraging. According to Andy Douglas, National Sales Manager, Specialty Markets for Kenworth Truck Company, the CNG-powered refuse or cement truck receives a $10,000 credit for not requiring the SCR after-exhaust treatment system needed in diesel models. The natural gas heavy-duty engine (Cummins Westport 8.9 L model) costs an additional $10,000. Thus, the base natural gas-powered truck costs no more than a diesel model.

According to Jeffery Swertfeger, Director of Marketing and Communications for McNeilus Truck and Manufacturing, a company that puts refuse and cement bodies on Kenworth trucks, the CNG fuel system costs an additional $25,000. But, Leo Thomason points out, there is a $32,000 federal tax credit available for CNG-powered heavy-duty trucks, thus providing a $7,000 excess credit beyond the cost of the vehicle.

Tax Credit Makes Payback Quick

Thomason explains that prices per diesel gallon-equivalent (DGE) vary among locations, but fuel savings generally range from $.40 to $2.00. In addition to receiving the $7,000 excess federal tax credit, a CNG-powered refuse truck using 50 DGE for 250 days per year at $.93 per DGE would save $20,000 to $25,000 per year on truck fuel.   Even where the fuel cost is $2.59 per DGE, there would still be a savings of over $1,000 per year, plus the tax credit.

Kolodziej from NGVA expects that with increasing production volume of heavy-duty CNG trucks, and with possible increasing competition, the price differential between diesel and CNG will diminish. “Will it ever be the same? Probably not, because of the cost for the CNG tank. But the costs of a CNG truck will become closer to the equivalent diesel model.”

 Friendly Regulation and Legislation

The U.S. EPA has issued rule modifications to make the conversion of gasoline and diesel engines to natural gas less restrictive and easier to achieve from engine family to engine family, and from year to year. Several federal bills are pending to add tax credits for bi-fuel (gasoline/CNG) and dual-fuel (diesel-natural gas) and to double the tax credits for CNG and LNG fueling structures.

For CNG vehicles that are not garaged at a central location daily, it is important to have access to high-speed refueling stations. Growing networks of public-access CNG fueling stations are already in place in California, Arizona, Nevada, New Mexico, New York, Texas, Wyoming, Oklahoma and Georgia. A network of stations is developing in Utah, with strong support from gas utility Questar Gas.

CNG for the Future

According to Darren Shepherd from Questar, the utility believes that natural gas is well positioned to meet U.S. energy needs and still reduce emissions. He says, “Many people have called natural gas a bridge fuel. Now it is clear that natural gas is more than a bridge fuel; it is a superhighway to a lower carbon future.” Part of the key is discoveries of new natural gas fields and the development of shale gas extraction technologies. Shepherd explains, “The new, abundant natural gas supplies may be the catalyst for America’s commercial transportation market to make the jump to CNG and do it without drawing upon traditional supplies used for residential and manufacturing markets.”

Barriers Coming Down

Shepherd notes that several reasons had been given by fleet operators for not adopting CNG-powered vehicles. “They cited limited refueling infrastructure, few engine-size options, high incremental vehicle costs and lack of governmental incentives and the previous relatively low cost of petroleum fuels. These barriers are fading, and furthermore, owners are becoming educated about the ease and independence that comes with onsite CNG refueling and the growing availability of CNG-powered engines and vehicles.

Questar has already built 19 public CNG stations along major highways in Utah where consumers can buy natural gas for less than half the cost of gasoline or diesel fuels. The State of Utah also opened six of its CNG stations to the public. where the same low price prevails. Added to this are the 50 companies that have onsite private CNG refueling stations.

CNG Excitement in Utah

Utah is seeing an increase in the number of refuse trucks and home-based delivery vehicles switching to natural gas. Shepherd indicates that one company in particular is a global food marketing and distribution company. Two of the world’s largest beverage companies are running delivery vehicles on CNG and many Utah school districts are adding CNG-powered buses. One Utah shuttle service provider runs eight CNG vans that average between 120,000 and 140,000 miles per year. Shepherd says, “Some of the vans now have more than a million miles on them. The owner will be the first to tell you CNG is profitable and his customers see the business as eco-friendly.”

Educational Tools are Available

For truck fleet operators, additional information is available from several sources. The Natural Gas Vehicle Institute offers a wide array of courses on natural gas vehicles and fueling station operation. Other sources include DOE/Clean Cities, NGV America, and the National Alternative Fuels Training Consortium located at West Virginia University.

In a growing number of places, CNG networks are growing and with them the numbers of fleets and individual vehicle operators. Important roles are being played by the federal government, by promotional and educational organizations, and by local and regional natural gas utilities. Darren Shepherd summarizes well the potential for natural gas transportation. “We have an abundant supply of domestic natural gas that can be used to move our products, protect our environment, and provide jobs.”