They’re hailed as the clean, green and climate-friendly future of our roads. But how do the eco-credentials of electric vehicles really measure up compared to conventional cars?
Electric cars have no tailpipe emissions and run on batteries, so they're kinder to the planet than conventional fossil fuel vehicles while they're being driven.
But that's not the full story - there's the environmental impact of their manufacturing and disposal to think about as well.
I high uptake of electric cars means cleaner air, which is especially important in highly populated areas where pollution from conventional cars contributes to poor health.
They also produce far less noise pollution than cars with combustion engines, leading to quieter towns and cities.
But how does the way electric vehicles (EVs) and their lithium-ion batteries are manufactured affect their eco footprint? And what about the environmental impact of charging a car using electricity from non-renewable sources?
The good news is that the ‘lifecycle emissions’ of an EV (the total emissions from manufacturing the vehicle and its battery, as well as emissions created during its fuel-powering cycle and use), are between 18% and 87% lower than a conventional petrol or diesel car, according to research by BloombergNEF.
The UK government is working to reduce the country’s net emissions of greenhouse gases by 100% (relative to 1990 levels) by 2050.
EVs play a vital part in helping reach these climate change goals and the government has set targets to:
The lifecycle of an EV affects the environment in three stages:
The process of manufacturing electric cars can create higher emissions than the manufacture of conventional cars. And although this doesn’t outweigh the environmental life-cycle benefits of an EV, it’s an issue that manufacturers are working towards addressing.
The main problem is that the production of lithium-ion batteries in EVs requires large amounts of energy.
The mining and refining of the raw materials used in lithium-ion batteries - such as lithium, nickel, graphite and cobalt - create a lot of emissions, as well as posing the risk of water and soil contamination.
The countries where these battery factories are based usually use a lot of non-renewable energy, but this is improving as more car companies look to reduce their carbon footprint and electricity companies around the world move to cleaner energy.
Carbon emissions from lithium-ion battery production are quickly offset - usually within two years - once an EV is on the road. That’s because, unlike conventional cars which continue pumping out emissions through their lifetime, electric cars produce no tailpipe emissions.
Charging your car using electricity created by burning fossil fuels produces emissions.
So, to keep your EV carbon-footprint as low as possible you could aim to use electricity sustainably generated from green and renewable sources instead.
If you have solar panel electricity installed at home, then you can install a charger that's compatible and plug in for free, zero-carbon charging. Or you could switch to an energy company that provides renewable energy.
Many eco-energy companies offer specialist EV energy tariffs which can include incentives such as cheap overnight electricity (when you’re more likely to be charging your car) or even free energy at off-peak times.
Like conventional cars, EVs do emit particulate matter (microscopic particles released into the air) from tyre wear, road wear and brake dust. But thanks to regenerative braking in EVs, where the electric motor switches from powering the wheels into generator mode and slows the car down, then emissions from brake pad abrasion are much less than from conventional cars.
Most electric car batteries come with warranties of between five and eight years. But it’s estimated they will typically have a lifespan of 100,000 to 200,000 miles and at least 10 years.
The EV industry is looking at ways to make sure lithium-ion batteries are sustainably managed when they reach the end of their life and keep them out of landfill where they can cause pollution.
Many car manufacturers are experimenting with schemes to give their used lithium-ion batteries a second-life.
For example Nissan and Volvo are looking at using second-life batteries as energy storage systems for homes and businesses.
Only a small amount of EV lithium-ion batteries have so far come to the end of their lives. But as more and more EVs are being sold there’ll be millions to recycle. That’s why industries and research teams are working on improving mass recycling infrastructures and techniques. Car manufacturers are also investing billions in recycling schemes.
The process of recycling EV batteries can be costly and complicated.
Researchers working on The Faraday Institution project on the recycling of lithium-ion batteries (ReLiB) have recently announced a way to extract valuable material from the battery which is quicker, greener and leads to better purity of the recovered materials than current methods.
The use of new techniques like this, as well as calls for the production of lithium-ion batteries that are easier to dismantle should lead to more effective recycling, further decreasing the carbon footprint of an EV.
Hybrid cars have electric motors as well as a petrol or diesel engine as their power sources.
The level of emissions you produce while driving a hybrid will depend on how much time you spend in full electric or petrol mode.
If you mostly use your hybrid car on short, slow journeys in towns and cities, using just the battery power, (and if you also charge your plug-in hybrid using only renewable energy), then you’ll be producing no emissions.
However, if you tend to do mostly fast journeys (such as motorway driving),when you’ll need the back-up of the petrol or diesel engine, then you’re likely producing similar emissions as a traditional car.
EVs are already more affordable than they were several years ago. And the government’s plug-in car grant, which offers a £2,500 discount on the cost of buying a new electric car, could come to an end in the next few years.
Although there will undoubtedly be advancements in how environmentally friendly electric cars become in the future, if you’re keen on helping to protect the planet, then now could be a good time to go electric.