|The global natural gas vehicle fleet has grown rapidly in the last 10 years, but still represents less than 1% of global transport fuel consumption. Click to enlarge.|
A new working paper published by the International Energy Agency (IEA) concludes that natural gas can play a significant role in cutting on-road vehicle carbon dioxide emissions, but that over the long term there will need to be a commitment to transition to very low CO2 gas sources, such as biogas or bio-synthetic gas. Natural gas may be especially important for cutting CO2 emissions from heavy-duty vehicles (HDVs) since other options such as electrification appear to be limited, the paper, written by Michiel Nijboer, notes.
The paper, which evaluates the potential costs and benefits of using natural gas as a vehicle fuel for road transportation, as well as the policy related to its market development, is intended to elicit comments and debate. As such, it is not an official expression of the IEA or a policy statement.
The global natural gas vehicle [NGV] fleet has grown rapidly over the last ten years, starting from a very low base of little more than one million vehicles to a current estimate of just more than 11 million vehicles. The global fleet of NGVs consists largely of passenger cars/LDVs, although there are some regional differences. According to the paper:
- 44% of all NGV passenger car/LDVs are in Latin America
- Almost two-thirds of all MD/HD natural gas buses are in the Asia/Pacific region
- 53% of all natural gas trucks are in the Russian Federation and CIS
- 78% of all other vehicles on natural gas (3-wheelers and tuk-tuks) are in Asia-Pacific.
NGV [natural gas vehicle] programmes are usually driven by other goals than greenhouse-gas reduction, although NGVs can certainly contribute to decarbonising transportation and as such should be part of plans to move towards sustainable transport. On average, a 25% reduction in carbon dioxide equivalent (CO2-eq) emissions can be expected on a well-to-wheel (WTW) basis when replacing gasoline by light-duty vehicles (LDVs) running on compressed natural gas (CNG).
While the technology for bio-synthetic gas is not fully developed yet, biogas could provide significant quantities of a low-carbon fuel in the longer term at low or even negative greenhouse-gas abatement costs. Europe is currently seeing an increasing number of projects aimed specifically at the production of biomethane and its use in vehicles. In principle, NGVs can also provide a pathway to hydrogen but more research is required to assess how and to which degree this can be accomplished. For various reasons, the potential to reduce greenhouse-gas emissions by replacing large quantities of diesel fuel consumption in HDVs by natural gas has been underutilised.—“The contribution of natural gas vehicles to sustainable transport”
Among the other key messages of the paper are:
Despite strong past and continued growth in the number of natural gas vehicles (NGVs) and fuel stations, natural gas is still a niche market in transportation, representing less than 1% of world road fuel consumption and less than 1% of world gas demand.
Vehicle and fuel technology for natural gas is available today and relatively affordable, particularly in comparison with other alternative fuel vehicles (AFVs).
Depending on the context, NGV can have strong benefits in different countries including: improving air quality and reducing noise in urban areas; diverting oil from domestic consumption to export; improving energy security; and reducing government spending on road fuel subsidies.
- Governments should carefully consider the role of NGVs compared to other AFVs, such as electric, fuel cell and biofuel vehicles, and weigh the costs and benefits of each for different modes of transport. In this context, it appears that NGVs may compare favorably in many—but perhaps not all—national contexts.
Natural gas can be competitive with gasoline where transmission and distribution grids are present; in countries where this is not the case, there is often an opportunity for simultaneous gas market development and increasing NGV market share. While investments in vehicles and retail infrastructure can generate positive returns, temporary government support may be required to establish an NGV market. Without such support, many countries are unlikely to achieve self-sustaining NGV markets with substantial penetration levels. Investments in grids are likely to take place only where other sectors can also benefit from natural gas supply.
The paper uses Brazil, India, Iran, Pakistan, the US and Europe as case studies.
The Contribution of Natural Gas Vehicles to Sustainable Transport (IEA working paper)