Are electric cars better for the environment than conventional cars?
Although electric vehicles (EVs) have been heavily marketed as environmentally friendly, exactly what is the benefit of driving an electric vehicle over a conventional vehicle?
EVs are accepted by many as an important way of reducing carbon emissions, but some are concerned that they may not be as environmentally friendly than standard petrol or diesel cars, due to their manufacture/components and also their use of grid electricity (which is not carbon free) . We look into the different stages of vehicle life cycles to inform you on the impacts both electric cars and fuel based cars have on the environment.
Did you Know? The carbon emissions associated with a year of charging a mid size EV in UK (Nissan Leaf) over 10k miles - more than a return flight from London to New York. Offset carbon emissions.
EVs are sometimes wrongly thought of as 'zero emission' - unless they are charged using renewable energy - this is untrue because of course grid electricity production causes and carbon emissions and is different tin every country (due to the different 'mix' of renewables and other fossil based sources of fuel).
In the UK for mid-sized cars
- EV produces about 75g CO2/km caused by vehicle charging from the mains.
- Petrol car emits ca. 130gCO2/km
- Diesel car emits ca. 99gCO2/km.
However the emissions associated with EV usage can be reduced significantly if electricity is generated using less carbon incentive fuels or renewable energy - e.g. charging from your rooftop solar panel array.
This of course fails to consider the benefits that EVs don't emit particulates and nitrous oxides - which are major health concerns in built up areas .....more on this later.
What difference does the country you live in make?
Countries that generate electricity from predominantly renewable energy ( e.g. Paraguay, Iceland etc), - charging EVs from the mains will have a much lower carbon footprint.
However for countries which have high usage of coal in generating their electricity, the carbon emissions from using electric cars are much higher, and in some gases actually exceed that of petrol and diesel vehicles.
What are the emissions associated with manufacturing?
It's estimated vehicle manufacture adds to a car's overall footprint by the following amount
- EVs 70gCO2/km
- Petrol & diesel cars 40gCO2/km
Battery production for EVs uses precious metals that can be extremely carbon intensive.
However, as manufacturing processes become more carbon efficient and battery life increases, so the EV manufacturing emission ( in g/km) will decrease.
What about end life emissions?
As time moves forward, EV batteries will last longer and may have a second life as domestic storage batteries - so reducing the overall carbon impact
What other emissions are caused by cars?
Air pollution is a major global issue which is causing premature deaths and illnesses throughout the world. The majority of air pollution in developed countries is caused by traffic which is especially prominent in towns and cities due to the congestion. Air pollution associated with conventional vehicles includes Nitrogen oxides (NOx), Particulate Matter (PM10) and Carbon Monoxide (CO) which are emitted from exhausts due to the burning of fuel. Diesel emits four times the amount of NOx and 22 times the amount of PM10 that the average petrol vehicle. The example cars in this article are Euro 6 standard, the strictest standard for emissions and the quantities of NOx and PM10 emitted can be seen below. EVs do not produce any exhaust emissions unlike conventional vehicles and are clear winners in reducing urban air pollution.