Written By: AGA’s Vice President of Policy Strategy Kathryn Clay, Former Sen. Pete Domenici (R-N.M.) and University of Texas at Austin Professor of Mechanical Engineering Raymond L. Orbach
While electric vehicles have captured news headlines, a second revolution has been quietly gaining traction in the U.S. transportation sector. Over the last five years, more than $450 million of private sector capital has been invested in natural gas fueling infrastructure. In fact, a technological breakthrough has enabled the development of both fuel storage enhancements and lighter stronger tanks that promise to increase range, reduce vehicle weight, and lower vehicle cost. Add historically-low natural gas prices to the mix, and these developments now position vehicles powered from natural gas to gain great market share within the transportation sector.
Natural gas vehicles have long suffered from a consumer perception of being “boring.” This perception has spread because the majority of compressed natural gas vehicles sold to date have been relegated to fleets, such as buses and delivery vehicles, where municipal governments and large corporations can take advantage of central fueling stations to reduce infrastructure costs. For many individuals, their first encounter with a natural gas vehicle is a city bus, a United States Post Office delivery vehicle, or the car carrying the parking enforcement officer who just wrote you a parking ticket – not exactly the flashy marketing that surrounds the launch of most new vehicles today.
But all of this is changing, and with it, the country stands to gain profound energy security and environmental benefits. Private companies, including many natural gas utilities, are investing in natural gas refueling stations. As a result, the total number of compressed natural gas (CNG) stations nationwide has grown by nearly 80 percent since 2009. The site locations are based on customers’ demands that CNG fueling stations be built near their key shipping lanes with proximity to major interstate highways. On the liquefied natural gas (LNG) side, Clean Energy Fuels has built a network of fueling stations along the I-40, I-10, and I-95 highways that support long-haul heavy-duty trucking, offering a viable alternative to diesel fuel for moving goods around the country. And although the truck market may be small in absolute numbers, these vehicles travel great distances every year: medium- and heavy-duty trucks consume upwards of 90 percent of all diesel fuel used on highways in the United States.
Recent breakthroughs in metal-organic frameworks have been demonstrated to store up to three times the quantity of natural gas that would be contained in a conventional CNG tank at the same temperature and pressure. One gram of a metal-organic framework has the surface area equal to the size of a football field. This new storage capability has the potential to solve the range shortcoming that has plagued CNG vehicles, bringing the potential range on par with gasoline-fueled passenger cars.
On the fueling infrastructure side, the cost of home fueling infrastructure for a CNG vehicle is currently about $5,000. However, this too is on the verge of becoming dramatically cheaper, with companies like GE and Eaton in the process of rolling out new CNG fueling units at a tenth of the current cost, plus installation. Such a development means drivers might only stop at a gas station for a coffee.
In addition to direct combustion of natural gas, hydrogen can be easily produced by reforming natural gas. Fuel cells utilizing hydrogen can propel vehicles electrically, with ranges comparable to current gasoline powered automobiles. Hydrogen fueling stations are becoming more common, and automobile manufacturers are producing hydrogen-powered fuel cell cars in new 2015 models that emit only water vapor out of their tailpipe.
The bright prospects for vehicles that rely on natural gas truly is “good news” for the country because these vehicles provide much-needed diversity to the transportation sector, which is currently dependent on petroleum—and the perils of global oil markets—for more than 90 percent of fuel consumption. Similarly, vehicles that rely on natural gas can offer tremendous optionality in the face of a global oil crisis, and also free up U.S.-produced petroleum products for our allies in times of need.
Although the progress has been great, this is not yet the time to pat ourselves on the back for a job well done. The natural gas technologies for transportation coming to fruition today are a direct result of a long-term commitment to basic research and development of alternative technologies from both industry and government. As we take stock of government spending—which we agree must be reduced in order to keep the national debt at a sustainable level—we should strive to make the strategic investments that the scientists and engineers tell us are needed. Furthermore, bringing these technologies and supporting infrastructure to market will also require us to look at other factors, including siting and zoning for natural gas and hydrogen refueling stations, and calculating fuel economy standards across a range of technologies. Looking forward, vehicles relying on natural gas hold great promise, but our work is not yet finished until those promises become reality.