CNG Perspectives as an Alternative Fuel for Transportation

By | 2017-05-15

As it is now mostly agreed that the anthropic exploitation of fossil fuels has a major role in the evolution of climate change, alternative energy sources are developing fast. If solar, wind, hydroelectricity, nuclear, etc. all present considerable benefits, their relevance and capacity to meet the energy demand vary widely according to geolocation. On the other hand, CNG has great perspectives to be used as an alternative fuel for transportation.

Current Circumstances Point Towards Natural Gas for Transportation

More specifically for transportation, in view of the continuous rise in energy demand worldwide, it seems that we are yet far from an eventual complete transition from fossil fuels, especially at global scale considering the large political spectrum that we face. Thus, a good solution to gradually complete this transition resides in the cleanest fossil fuels: Natural Gas.

Here is a brief overview of six reasons indicating why it makes sense to develop more natural gas as an alternative fuel for transportation for heavy trucks, as well as for smaller cars and trucks where there is no other alternative renewable fuel available:

    1. Natural gas is cheaper than gasoline and diesel, partly because it does not need to be transformed through a highly polluting process to be used for transportation. It must only be compressed or liquefied.
    2. Natural gas is the most available fossil fuel on the planet, and the cleanest with lower vehicle emissions in comparison with diesel of up to -15% carbon dioxide (CO2), -70% nitrogen oxides (NOX), -99% particulate matter (PM), -90% non-methane hydrocarbons (NMHC), and overall roughly -25% greenhouse gases (GHGs) emissions.
    3. Natural Gas Vehicles (NGVs) are only slightly different than the usual vehicles fueling on gasoline or diesel. Also, vehicles fueling on gasoline or diesel can easily be converted to natural gas with a specially designed conversion kit without changing the engine, requiring mainly a new fuel tank, new injectors, and some electronics.
    4. Natural gas is a safer fuel than gasoline and diesel since it will evaporate in the case of a leak caused by an accident because it is lighter than air, therefore considerably reducing the risks related to a flammable liquid fuel.
    5. Natural gas as we know it is a fossil fuel, but since it is fundamentally methane (CH4), it can also be obtained through the process of anaerobic digestion in a digester or in landfills, earning itself the name of Renewable Natural Gas (RNG), or Biomethane, a renewable fuel completely carbon neutral as well as completely compatible with any natural gas infrastructure such as the gas distribution grid, or any NGV.


Natural gas can be either compressed (CNG) or liquefied (LNG) to allow a sufficient energy density to be suitable for transportation, depending on the type of vehicle. Long haulers and heavy trucks generally use LNG because it has twice the energy density of CNG.

But since it is much more difficult to store than CNG, LNG must be consumed in a relatively short time lapse. This is mainly why we currently face good perspectives of CNG as an alternative fuel for transportation regarding cars and short radius vehicles such as waste collection trucks or municipal buses.

Policies & Government Blow in the Sails of CNG for Transportation

Many fiscal and regulation incentives have been helping the NGVs and CNG industries in the past years. For example, Italy was already granting approximately 2,000€ in 2007-2009 for the conversion of a vehicle to natural gas.

Also, the European regulation 443/2009 is the fundamental reason that has motivated vehicle manufacturers to lean towards NGV technology in the past years. Following is a great excerpt from Landi Renzo’s presentation at the ALTfuels Mexico 2017 Conference last April, which summarizes clearly and simply the regulation:


It sets standards for new passenger cars regarding their carbon dioxide (CO2) emissions. The current limit is set at 130 grams of CO2 emitted per kilometer. The limit will drop to 95 grams of CO2/km by the year 2021.


130g/km limit phased in between 2012 and 2015. For every year in that period, the percentage of a manufacturer’s cars that must comply with the limit increases. From 2015 100 % of cars must comply (compared to 75 % in 2013 and 80 % in 2014).

If the average CO2emission from a manufacturer’s number of cars exceeds the emission limit, then a heavy fine will be enforced. For each car, the manufacturer must pay €5 for the first g/km over the limit, €15 for the second, €25 for the third and €95 for every g/km after that. From 2019, every g/km over the limit will be charged at €95.

Small manufacturers that register fewer than 1,000 cars in the EU per year are exempted from this legislation, whilst those that register between 1,000 and 10,000 cars per year can propose their own emission reduction targets. Meanwhile, manufacturers in the 10,000 -300,000 cars per year range can apply for a fixed reduction target.

A system of emission credits and super credits rewards eco-friendly innovation carried out by car manufacturers.”

CNG Technology is Mature, Efficient & Safe

Finally, CNG as a transportation fuel is a mature technology complying with up to date safety standards. Furthermore, it is a technology that is efficient for its use in transportation as well as for its potential to reduce vehicles emissions in order for vehicle manufacturers to meet the targets established by government regulations, which can lead to heavy fines if not respected, as just mentioned.

Let’s also not forget that CNG is also obviously much better for our environment than more conventional fossil fuels such as gasoline and diesel, and that its infrastructure is 100% compatible with those of renewable natural gas, or biomethane, a 100% carbon-neutral alternative fuel.

With over 23 million NGVs across the world and a worldwide CNG filling network growing of around 5% in average each year (the highest growth being met in Europe where Italy is expected to double in number by 2022), everything tends to indicate that CNG will be part of the transportation fuel environment for a long time.

One can also assume that the development, growth, and implementation of anaerobic digestion and biomethane infrastructure will fulfill an even greater power push to CNG as a sustainably established fuel for transportation.