Adopting Compressed Natural Gas Vehicles
In our last Mobility Matter’s post, the benefits of compressed natural gas (CNG) as an alternative fuel were discussed. The second part of this discussion, presented below, delves into the barriers to adoption and discusses some of options currently available to help overcome these barriers.
Barriers to Adoption
While the market for NGVs has seen steady growth due to a plentiful supply of natural gas and the desire to reduce severe air pollution, the U.S. and other developed countries have encountered barriers toward the adoption of CNG.
One barrier is the cost to the consumer of CNG-capable vehicles, which can be 20 to 30 percent more expensive than a comparable gasoline-powered vehicle. While drivers of NGVs experience savings on fuel cost and maintenance, a study conducted by the National Energy Policy Institute found that for a commercial truck to obtain a 20 percent ROI after converting to natural gas it has to drive about 70,000 miles per year. For long-haul truckers this is an obtainable number. Based on information from the U.S. Department of Energy a new class 8 truck can travel up to 150,000 to 200,000 miles annually. While an increase in demand for the technology could drive the overall cost of the vehicles down, the problem of how to create demand remains. Consumers need to be educated about the many benefits of NGVs and believe that these benefits outweigh the higher initial investment of purchasing a CNG vehicle.
Another concern is that the fuel range of NGVs is lower than similar gasoline-powered vehicles due to the lower energy capacity of natural gas and the fact that most engines have not been designed to take advantage of the higher octane rating of natural gas compared to gasoline or diesel. Fuel range can be increased by using larger fuel tanks; however, these tanks are much heavier and can be a problem for fleet vehicles that already run at maximum payload capacities and often take up valuable trunk space in light vehicles.
Recently, there have been advancements in the use of adsorbed natural gas (ANG) storage systems that could dramatically reduce the costs associated with natural gas fuel systems by storing the natural gas at a lower pressure than traditional CNG fuel systems. ANG storage systems hold the same amount of fuel but require less energy to fill due to the lower storage pressure than current CNG fueling systems. By adopting the ANG fueling system, NGVs will have better fitting fuel tanks and potentially twice the current fuel range. In terms of engine design, the engine efficiency of purpose-built natural gas engines will be at least equivalent to, if not higher than, gasoline engines and may match the efficiency of diesel engines.
Finally, a recent survey conducted by NGV Today revealed that one major concern is the lack of easy access to fueling stations. In Europe, fueling stations are on the rise but not spread equally throughout the continent. The U.S. has a similar problem; the Northeast coast, California, and Oklahoma boast a high concentration of fueling stations while other states do not have any. One potential solution to the lack of public fueling stations is to highlight the ease of refueling at home. Home fueling stations can be attached to existing natural gas lines and slowly refill at a rate of about one gallon per hour.
As you can see, CNG is a promising alternative fuel that comes with its own set of pros and cons. Both commercial and light-vehicle drivers contemplating the adoption of CNG will have to consider making several trade-offs. For example, CNG engines are lighter, quieter, and cheaper than diesel engines, but the fuel storage tank is heavier and more expensive. Also, as stated earlier, CNG is less expensive than diesel but it is also less efficient and there is limited refueling infrastructure in place. Future investment in NGV technology and infrastructure will help CNG become more attractive by making the necessary trade-offs less significant.
Dana is excited about the possibilities for growth within the NGV market and would like to hear your thoughts on the adoption of CNG.
- What do you think is the greatest barrier toward CNG adoption?
- What do you think are the greatest advantages and greatest challenges to home fueling? Would you use it?
Published by Eve Steigerwalt