It’s all relative
An electric vehicle will generally be more environmentally friendly than a comparably sized combustion engined or hybrid vehicle. However, it is important to remember that ‘environmentally friendly’ is not the same as a car having absolutely no emissions or zero environmental impact.
This also means that while an electric vehicle may be more environmentally friendly than a similar non-EV, not every electric vehicle is more environmentally friendly than every hybrid or combustion engined car. To use an extreme example, GM’s latest Hummer EV, with a weight of more than 4 tonnes, is likely to have a greater overall environmental footprint than a small hybrid car.
Put simply, how environmentally friendly an electric vehicle is depends on a wide range of factors that can vary greatly. This includes everything from vehicle size, materials used to make key components such as batteries and motors, where the electricity used to charge the EV is sourced from, and even how sustainable the factory that made the vehicle is, with regard to the energy sources used for production. It is also important consider what happens to the vehicle once it reaches the end of its life, especially in relation to how recyclable, and biodegradable, the materials used in the EV are.
Consequently, there are two ways to look at how environmentally friendly an electric vehicle is. The first relates to the footprint of the vehicle itself, and the second is a more holistic, lifecycle consideration of the emissions and other environmental factors related to the vehicle, often known as ‘well-to-wheel’ emissions.
One of the most environmentally friendly features of an electric vehicle is that they do not produce any tailpipe emissions. This ensures that an EV does not contribute to harmful air pollution, and a wide adoption of EVs may help reduce smog levels in a city.
Additionally, apart from any legislative requirements to provide a low-speed audible warning to pedestrians and other road users, an electric vehicle is also silent, minimising noise pollution. This ensures that neighbours and other members of your household will not be disturbed by your electric vehicle leaving and arriving your residence.
Overall well-to-wheel emissions
The ‘well-to-wheel’ measure is a more holistic, lifecycle approach to considering how environmentally friendly the vehicle is, and incorporates a wide variety of factors. The full range of these is beyond the scope of this story, however, some key considerations are outlined below.
The materials used to build an EV can significantly affect its environmental friendliness. Many electric vehicles continue to use motors incorporating rare earth metals such as neodymium, while batteries may use materials such as nickel, cobalt and lithium. The mining of these materials generates its own environmental impact, not just in terms of carbon emissions, but also deforestation and potential degradation of local habitats. To address this, at least partially, many carmakers are turning to certified mines with responsible and transparent mining practices, and are designing batteries and motors that require reduced amounts of nickel, cobalt and rare earth materials.
Another related consideration is the recyclability, biodegradability and overall sustainability of the materials used in an electric vehicle, and this is especially relevant for interior trim where various plastics and other material types may be used. For example, Volvo with its latest EX90 claims 15% of the total plastic used in the car, equivalent to 48 kg, are from recycled sources. Meanwhile, other manufacturers such as Fiat in its latest 500 electric are turning to materials such as Seaqual for the seats, which is a fibre made from recycled plastic and sourced partly from marine litter.
The source of the electricity used to charge an EV’s battery is also an important variable to consider. If an EV is charged with energy mostly, or exclusively, from renewable sources such as solar or hydroelectricity, it will have significantly lower overall emissions than a comparable EV charged using traditional non-renewable energy sources such as coal.
The emissions of the factories and overall supply chain used to build these EVs are another related concern. As an example, the now superseded BMW i3 was made exclusively in the company’s Leipzig factory, where the electricity used to build the vehicle was generated from four on-site wind turbines. Meanwhile, the carbon-fibre used to build the car’s chassis was forced from an American factory powered through hydroelectricity.
When taking all of these factors into account, there may be significant overlap between the overall environmental footprint of an electric vehicle, compared to other types of hybrid and combustion engined vehicles. Nevertheless, it remains likely that an EV will be more environmentally friendly than a similar non-EV.