On its own, natural gas as a fuel for both light- and heavy-duty vehicles has vast potential to significantly reduce the GHG emissions from transport.
However, blending it with renewable gas contributes to further transport decarbonisation and offers significant emissions reduction potential for the future.
In order to understand this better and account for it in an accurate way, we need to look at the lifespan of the vehicle and not just what the vehicle emits.
What is meant by “full lifespan” of a vehicle?
Generally outlined, this is the consideration of all aspects that contribute to the production of CO2: production of the vehicle, fuel effect, use of that fuel by the vehicle to produce movement and finally the disposal or recycling of the vehicle at the end of its life.
When taking into account the full lifespan of a vehicle, natural gas as fuel is one of the most effective solutions to fight climate change and improve air quality in a cost-efficient way.
At a minimum, a Well-to-Wheel approach (fuel and vehicle emissions) has to be part of the methodology to calculate CO2 emissions and evaluate solutions for transport decarbonisation.
Note: current legislation is set so that what you see on the vehicle information sheet only shows what the vehicle emits as CO2. In other words, the energy needed to move the vehicle, its production and recycling emissions are not part of that number.
Thus, this number on its own (Tank-to-Wheel emissions) cannot be representative of the full picture, making it an ineffective factor on which to compare vehicle emissions.
What can be done about that?
To begin with, a CO2 reward mechanism should be offered to car manufacturers, according to the amount of renewable gas traded to the transport sector. A similar approach already in use in Switzerland is adding 10% of biomethane into the gas mix.
The 10% mix of biomethane means that a natural gas vehicle producing 100 gCO2/km in Switzerland is homologated (officially labelled) as 90 gCO2/km. This is already a step forward in the right direction that a non-EU country has correctly decided to implement.