Sustainable mobility: Gas fuel as an efficient answer to environmental challenges

Introduction: Sustainable mobility main issues

The transport sector is the world’s first oil consumption sector. This situation can be explained by a very strong and growing energy demand (around a third of the global energy demand) and the monopoly position of oil in the energy mix of the sector.

This dependence raises a number of issues: on the one hand the emissions of local pollutants (NOx, fine particles, etc.) trigger a public health issue, and CO2 significantly contributes to global warming. On the other hand, the entire sector is exposed to the volatility of petroleum products prices. In France, the transport sector is responsible for 30% of greenhouse gas (GHG) emissions, 16% of fine particulates emissions and almost 50% for nitrous oxide (NOx).

In response to health and environmental challenges, the government has set ambitious and increasing objectives. These targets deal with the reduction of greenhouse gas emissions (reduction of 30% of GHG emissions emitted by the sector between 2015 and 2028 fixed by SNBC, integration of 10% of RES in transport in 2020 set by the French energy transition law for green growth) and the reduction of pollutants at the local level with the apparition of Low Emission Zones (example of Crit’Air distinction). These objectives and constraints encourage the mobility sector to move towards less polluting motorization technologies, supported by incentives for alternative fuels.

Among these alternative fuels, natural gas (NGV) and hydrogen (H2) offer a relevant answer to the traditional fuels’ limits.


        I.            Natural gas for vehicles, a fuel with multi benefits!


NGV is a fuel that can take two forms: CNG (compressed natural gas which is natural gas in gaseous form) and LNG (liquefied natural gas). It represents natural gas use as fuel for mobility. It can be obtained from the exploitation of fossil gas deposits or by anaerobic digestion of biomass (methanization)[1].

NGV offers several ecological and economic benefit:

  • – Currently, natural gas reserves are bigger than oil reserves. This gap could increase significantly in the years to come with the continuous discoveries of new deposits and the extraction technologies improvements; 
  • – Natural gas can also be produced by anaerobic digestion of organic waste. Then, we talk about about biomethane. Europe is the world’s leading biomethane production area. Thus, In France, in 2017, 406 GWh of biomethane were injected into the gas networks;
  • – Natural gas emits between 5% and 20% less CO2 than oil, in a “well to wheel” (WTW) comparison. Biomethane development makes it possible to approach a neutral carbon footprint (CO2 emitted equals captured CO2);
  • – Mostly composed of methane, natural gas emits practically no pollutants (SOx, NOx, fine particles, etc…);
  • – The cost of one MWh of natural gas is lower than the cost of one oil MWh. According to current projections, this tendency is expected to be maintained in the medium and long terms;
  • – NGV engines are 50% less noisy than diesel engines.


        II.            Hydogen for mobility


In the past few years, hydrogen mobility has been gaining spectacular interest, as illustrated by the creation of the Hydrogen Council announced by 13 business leaders from the Fortune 100 during the last World Economic Forum in Davos in February 2018. France is particularly active in this sector with several flagship industries.

Hydrogen, with its high energy density, could be a relevant technical alternative to conventional fuels in the transportation sector. Even if 95% of the global hydrogen is still produced using fossil energies (mostly for industrial sectors such as chemistry or petroleum refining), it can also be produced from biomass, biogas or by water electrolysis from renewable electricity. Electrolysis of water consists of separating hydrogen (H2) from oxygen (O) by applying an electric current between two electrodes.

A fuel cell installed in a hydrogen vehicle produces the reverse reaction of electrolysis by transforming hydrogen into electricity by reaction with oxygen. Thus, thanks to a fuel cell, hydrogen vehicles only emit water, they have an operating autonomy 2 to 3 times longer than electric vehicles running on batteries and recharge in only 5 minutes in suitable stations.


        III.            Applications for NGV and hydrogen vehicules.


In France, these new fuels, which are more respectful of the environment, are nowadays mainly used by heavy vehicles (transportation of goods, of passengers, urban buses, garbage dumpsters) and, to a lesser extent, by captive fleets of light commercial vehicles. This last category also includes vehicles with hydrogen-based engines (H2).


        IV.            French market state of the art for sustainable mobility


A sector concentrating multiple profiles of actors:


A booming market, driven by national structuring objectives:

In February 2017 France announced before the European Commission the objective to reach the deployment of 80 CNG refueling points in 2020. This objective has already been exceeded with 138 fueling points already deployed.

For LNG, the target of 25 fueling points by 2020 is also already achieved. Refueling stations continue to be developed, mainly in the periphery of major urban centers and all along strategic axes of freight transport (roads, logistics centers and major ports in particular).

Since 2015 and the repositioning of the sector toward heavy vehicles powered by public stations, the number of opening points on trucks has been expected to be multiplied by 6 between 2015 and 2018.

In terms of vehicles running on NGV, the fleet now stands at 16 100 vehicles (compared to 15 500 at the end of 2016). The multiannual energy program (PPE – Programmation pluriannuelle de l’énergie) sets the development targets for gas mobility in 2023 and expects 3% of heavy vehicles running on NGV. It would represent more than 25 000 vehicles.


A growth driven by heavy vehicles and, to a lesser extent, by light commercial vehicles:

In 2017, nearly 55% of the French CNG fleet vehicles are light vehicles or light commercial vehicles (LCVs). Due to the repositioning of the sector, the natural gas vehicles growth is now mainly driven by heavy vehicles and in particular by the transportation of goods: trucks (nearly 1 800 units mid-2018) and garbage trucks (BOM) do not face alternative energy on their segment. Passenger transportation vehicles, buses in particular, are more divided between electric and NGV.


A sector benefiting from state supports:

  • – Favorable tax measures: 5-years freeze of the domestic tax on energy products consumption (TICPE) for NGV, while the TICPE for diesel engines will continue to increase each year;
  • – Excess depreciation mechanism of 40% for trucks will be extended at least until the end of 2019 (financing on average half of the extra cost of NGV vehicles);
  • – Cheaper, or even free, registration card for NGV vehicles in certain regions;
  • – ADEME 2 calls for projects: a 1st with results in January 2018 to support 100 stations and the 2nd in progress called “GNV / bioGNV” which meets specific needs to ensure the distribution of NGV stations on the territory.


        V.            Conclusions on the French NGV and H2 development for transportations


In a context of energy transition and debates on the energy mix in France, sustainable mobility has become one of the most important concerns in Europe, especially as mobility needs increase each year. Pollution from oil products used in conventional fuels, its environmental and public health consequences, has led governments to move towards cleaner alternative fuels. Although electric mobility seems to have imposed itself as the reference on light vehicles, in France at least, natural gas for vehicle (NGV) is highlighted by public authorities in the passenger segment heavy vehicles. To support its development, the sector benefits from several financial mechanisms to promote the deployment of NGV, whether for fuel distributors or users.

Although it remains currently widely experimental, hydrogen technologies for mobility are seen as a relevant prospect with many emerging applications, from bicycle to goods transportation, through light vehicles, utilities, but also under prototypes in the rail, river and aviation sectors.