I am involved in a group in Turin, Italy, setting up a lab for sustainable mobility and there is lot of talks on hydrogen as a fuel, electrical vehicles (of different sorts) all of this under the umbrella of sustainability, lower CO2 emission, circular economy.
The more you look into the various aspects and the more complex the landscape. What would seem like a no-brainer, go for electric (or hydrogen) and you have zero emission vehicles turns out to be far from the truth.
Any vehicle starts to generate carbon emissions well before it has been delivered to the customer for the first drive and well after it has been decommissioned. Also, during its operation it will emit CO2 as far as 10,000 miles away from where it is actually driving.
Take a look at the first graphic (resulting from a study of Renault that includes the manufacturing part but not the decommissioning part): The blue lines relate to the electric car, the grey ones to the diesel version and to the petrol version (upper line). They represent the total emission of the car, first in the manufacturing phase and then in the operation:
- in the manufacturing phase the electric car generates more emission (less environment friendly);
- in the operation the emissions are highest for petrol fuel and then for diesel fuel. For the electric car the local emissions are zero, however the production of the electricity used by the car generates emissions and these depend on the way electricity is generated. The two curves represent the operation of the car in UK (upper blue line) and in France (lower blue line). The different in emissions (higher in the UK) depends on the use of coal plant as main electricity producer in UK versus the use of nuclear power in France;
- an electric car is therefore becoming more “environment friendly” after 1 to 2 years of operation (considering an average 15,000 km driven per year).
The study is an old one, going back to 2011, and it is only focussing on CO2 emissions and does not consider the decommissioning phase where again the electric car, and particularly the batteries, involves a higher CO2 emission and in general a higher impact on the environment,
The graphic on the side is based on recent data, 2020, and compares the emission of ICE -Internal Combustion Engine- with EV – Electrical Vehicles. The first bar shows the emission of a petrol fuelled vehicle, the second of a diesel one and the remaining bars show the emission of EV in different European Countries, where the contribution to emission during operation depends on the (average) emission of the source of electricity (the more it is based on renewable, the lower the emission).
The red line on each bar represent the expected level of emission by 2030, as better ICE engines will become available and more renewable sources will be used to generate electrical power.
Notice in this second graphic that in spite of the ten years lag from the first, the amount of initial emission from production remains higher for EV than for ICE. Production emissions are expected to decline in the coming years (as clearly shown in the case of France and Sweden where the total emission expected in 2030 is lower than today’s emissions deriving from the production phase).
The issue of decommissioning (the batteries) remains open and shall not be neglected for the potential pollution of billion batteries and the cost of recycling them.
This is just part of the story. The economic aspects are also very important. If you like differential equations take a look at this very interesting article that examines in depth the economic impact of various forms of propulsion (petrol, diesel, light EV, full EV, hybrid…). It is based on very recent data applied to the US market. Its conclusion are that, at least at the moment, hybrid vehicles (because of more limited use of batteries) are the ones that have the least impact on the environment….