Technology About Gas

Natural Gas on the move

 By Robin Wylie
About gas

Natural gas has recently been gaining attention as a way to decarbonize the energy sector, but this versatile fuel also has the potential to reduce the environmental impact of another great polluter—the transport sector…

Transport is responsible for approximately one quarter of humanity’s greenhouse gas emissions, making it the second most polluting industry behind energy. Reducing the carbon footprint of the transport industry will therefore be an essential step towards reducing humanity’s proven impacts on Earth’s climate. Ultra-low emission technologies such as hydrogen fuel cell and electric-powered vehicles, while extremely promising in the medium-to-long term, are still insufficiently mature to provide a large-scale replacement for traditional motor engines. But just as in the energy sector, natural gas has the potential to significantly reduce the carbon emissions of the transport sector, in the short term, with existing, and already widely-implemented technology.

When used as a transport fuel, natural gas produces up to 25 percent fewer greenhouse gas emissions per kilometer than diesel. It also emits almost zero sulfur oxides and particulate matter, which are produced in significant amounts by petroleum-powered engines and can cause respiratory problems. Although there have been questions raised over the lifetime GHG emissions of natural gas-based transport fuels, a recent review paper concluded that in most studies, the GHG emitted by diesel trucks exceeds that of LNG trucks “on a well-to-wheel basis.” In addition, the review found that the use of natural gas in transport could serve as a transition to the use of biogas in the coming years as long as a large-scale production at competitive prices is reached. The authors, from the University of Zaragoza, Spain, say that in the medium to long term, the development of infrastructure for natural gas distribution and partnership of a major LNG fleet could contribute to the introduction of biogas produced by the synthesis of CO2 and H2 with renewable electricity … or liquefied biomethane. GHG emissions per kilometer could decrease by up to 92 percent and 62 percent, respectively.

Natural gas already has a small but significant presence in the global transport sector. There are currently approximately 23 million natural gas-powered vehicles (NGVs) in operation worldwide, approximately 2 percent of the billion or so vehicles on Earth. The majority of these NGVs are located in Asia and South America, where in places up to 20 percent of vehicles run on compressed natural gas (CNG). Europe, by contrast, only has around 2 million NGVs in operation. Despite the continued dominance of petroleum-powered vehicles—which make up practically all of the remaining 98 percent of vehicles on Earth—in recent decades natural gas has seen impressive growth in the transport sector. The global fleet of NGVs has swelled from less than one million in 1996 to today’s 23 million. In order to make a significant reduction to humanity’s carbon emissions, the penetration of natural gas in the transport industry will clearly have to rise far beyond its current 2 percent share.

In Europe, where natural gas use in transport is relatively low, there have been recent steps towards increasing the implementation of natural gas in the transport sector. The European Union has stated that natural gas is one of the best alternatives for road transport in the short-to-medium term to reduce the environmental impact of its transport sector. The EU has also encouraged the construction of LNG re-gasification terminals to create new trading hubs in ports where there is no pipeline access to natural gas, as well as creating the “Blue Corridor” project, which has the target of building 14 new LNG stations in various locations across Europe in order to connect northern, central and southern Europe.

Eni plans to develop various projects for LNG storage

In Italy, which has the largest NGV fleet in Europe at approximately 1 million vehicles, Eni is present with 78 CNG stations, with a growing plan at a rate of 8-10 stations per year, and 2 LNG stations, with a growing plan of 2-3 stations per year. Moreover, Eni plans to develop various projects for LNG storage in order to supply their LNG stations and marine vessels. Eni is also actively involved in promoting the use of CNG and LNG for use in heavy and marine transportation, where it believes that the use of natural gas will be fundamental, as electrification of these sectors may be impossible in the long term. Looking forward, a recent drop in fuel costs bodes well for the potential of NG to expand in the transport sector. The LNG price at service stations is lower than that of diesel in most EU member states. The price of imported LNG fell by approximately 45 percent in the EU between 2012 and 2015. On average, LNG is currently around 44 percent cheaper than diesel in the EU.

The rise of LNG could is also helping to bring natural gas to parts of the world where the fuel had traditionally been unavailable due to lack of pipeline access. The Spanish study concluded that “the price of LNG in the EU is set to drop further [due to an] increase in supply from the US and Australia.” The authors believe that this price drop is encouraging news for the implementation of NG, and especially LNG, because the use of CNG has previously shown success in countries where the price is 40-60 percent below gasoline prices. They further recommend that “governments should promote LNG technology adoption directly to customers through tax reduction, benefits in tolls, reduced import tariffs for conversion kits and new vehicles, and subventions for the local development and manufacture of these technologies”.

SEE MORE: The rise of natural gas trucks by Peter Ward

about the author
Robin Wylie
Freelance earth/space science journalist. Currently finishing off a PhD in volcanology at University College London.