How ‘green’ are electric cars?
With the ban of new petrol and diesel cars in place in the UK by 2030, sales of electric cars are expected to surge. Plug-in hybrid and electric vehicles accounted for more than 1 in 10 vehicle registrations in 2020, up from 1 in 30 in 2019, according to data published by the Society of Motor Manufacturers and Traders.
The International Energy Agency predicts that by 2030, 125 million electric vehicles will be owned around the world and the UK government aims for almost every car and van on the road to be zero emission by 2050.
But just how green are they?
Electric cars are undoubtedly cleaner than fossil fuel run cars. Although more energy is required to make electric vehicles than petrol, you still save more energy in the long run. The deficit is paid off quickly and even, when with no alternative, the electricity used to charge the vehicles is driven by fossil fuels, they are still greener.
However, it is important to address the huge implications for our natural resources not only to produce green technologies like electric cars, but to keep them charged.
Challenges
For every car on our roads to be zero emission by 2050, just under double the current total annual world cobalt production, 75% of the world’s lithium production and at least 50% of the world’s copper production would be required.
Currently, electric cars rely on lithium and cobalt batteries to run, which, whilst undoubtedly better for the environment than carbon, aren’t entirely clean.
Cobalt mining
Cobalt is a key ingredient in the lithium-ion batteries that power electric cars, because it enables the energy density required in batteries intended to last for hundreds of miles per charge.
However, the mining of cobalt is fraught with political issues. 60% of cobalt comes from the Dominican Republic of Congo where children as young as 7 years old are mining it. The mining process also causes terrible pollution in local rivers.
Lithium-ion batteries used in electric cars and other consumer electronics account for about half of all cobalt demand, and the demand for these batteries is projected to more than quadruple over the next decade.
Lithium mining
Lithium is currently produced far from the UK — In 2019, Australia was responsible for more than half of global lithium supply, with the bulk of the rest supplied by Chile, China and Argentina. Lithium deposits are also located near some of the most sensitive ecosystems in the world – The Amur River, on the border of Russia and China, the Andes Mountains (Chile) and the Salt Flats in Bolivia. Deforestation, water shortages and toxic leaks are unfortunately a devastating consequence of lithium mining. Lithium extraction in salt flats in Bolivia uses millions of litres of water. The Sales de Jujuy plant produced 14,000 tonnes of lithium in 2018, using up to 420 million litres of water – the equivalent of 168 olympic sized pools.
Prof. Richard Herrington, Head of Earth Sciences Department, Natural History Museum said: “Society needs to understand that there is a raw material cost of going green and that both new research and investment is urgently needed for us to evaluate new ways to source these. This may include potentially considering sources much closer to where the metals are to be used.”
Recycling
Research in Australia found that only 2% of the country’s 3,300 tonnes of lithium-ion waste was recycled. Because lithium cathodes degrade over time, they can’t simply be placed into new batteries. “That’s the problem with recycling any form of battery that has electrochemistry – you don’t know what point it is at in its life,” says Stephen Voller, CEO and founder of ZapGo. “That’s why recycling most mobile phones is not cost effective. You get this sort of soup.”
At present, there are low volumes of electric-vehicle batteries that require recycling. As these volumes increase dramatically, there are questions concerning the economies (and diseconomies) of scale in relation to recycling operations.
Charging inefficiency
One of the biggest challenges, not just for the UK, but around the world is the installation of charging points. We need more, faster, more reliable charge points for people to be persuaded to take the plunge and purchase electric. Cars also need to be charged at smart times of day to avoid unnecessary costs for energy networks (and ultimately the consumers who pay for them).
Solutions
Sourcing locally
Luckily, lithium is relatively abundant, and could in theory be generated from seawater across the globe in the future.
In Britain, there are exciting developments in the lithium industry. Researchers working on ways to source lithium, a critical component of the batteries used in electric vehicles, have produced a chemical known as lithium carbonate from rocks found in Cornwall and Scotland.
Cornwall has a world-class mineral quality, which has stood idle for decades. The battery revolution provides the opportunity to explore raw materials which are vital to modern technologies such as electric cars. Cornish Lithium believes that the extraction of lithium has the potential to rejuvenate the economy of Cornwall and to provide much needed high value employment.
While the UK may not be a global player, to be able to produce what it needs would place it at a serious advantage over non-lithium- producing countries. It’s an exciting step forward which sets Britain on a good course to create its own EV supply chain in the next five years, which is especially important since the UK left the European Union.
Under the terms of the new free trade agreement with the EU, for goods sold in the EU to qualify as tariff free they must have components produced under localised sourcing. UK-based car makers need to have developed their own local battery supply chain by 2026 in order to avoid these charges.
Alternative resources
As mentioned above, resources like Cobalt aren’t infinite, and the environmental issues associated are prominent. We ideally need to shift to batteries that use less cobalt, or none at all. Elon Musk’s car firm Tesla will make electric vehicle batteries with cobalt-free cathodes, it announced during its Battery Day event in Autumn last year, but there is no set timeline on this yet.
For short-range cars made and sold in China, Reuters says Tesla will instead use lithium-iron-phosphate batteries, which are much cheaper and don’t have the same environmental problems as those needing cobalt. The disadvantage is that these batteries tend to have a lower energy density, reducing how far a car can drive without needing to charge.
Lithium-iron-phosphate batteries are already widely used by other Chinese firms, including BYD, the world’s biggest electric car manufacturer. If other electric car manufacturers follow internationally, we may be able to reduce our dependency on a dwindling mineral resource.
Recycling research
At the University of Birmingham, research funded by the government’s £246m Faraday Challenge for battery research is trying to find new ways of recycling lithium-ion. Researchers, led by the Birmingham Energy Institute are using robotics technology developed for nuclear power plants to find ways to safely remove and dismantle potentially explosive lithium-ion cells from electric vehicles.
A number of improvements could make the recycling processes economically more efficient, such as better sorting technologies, a method for separating electrode materials, greater process flexibility, design for recycling, and greater manufacturer standardization of batteries.
Battery swap shops
China, with electric vehicle sales of more than one million a year, is demonstrating how the charging issues can be addressed with battery ‘swap shops’ in which owners can drive into forecourts and swap batteries quickly. NIO, the Shanghai-based car manufacturer, claims a three-minute swap time at these stations.
This also addresses the high cost of EVs currently. By using the swap concept, the battery could be rented, with part of the swap cost being a fee for rental. This could reduce the purchase cost and incentivise more people to purchase electric. The swap batteries could also be charged using surplus renewable electricity, which is a real plus for the environment.
Electric alternatives
It’s the electric vehicles that have taken off in the world of green automotives. However, there is another player in the field – hydrogen. Hydrogen cars are powered by a chemical reaction. Hydrogen enters the fuel cell from a tank and mixes with oxygen to create H2O, which generates electricity that is used to power the motors that drive the wheels.
Hydrogen tanks are refuelled in a process that’s pretty much the same as with a petrol or diesel car. You could fill your car up just like fossil fuel, but instead of greenhouse gases being emitted, the exhaust would just be pure water vapour. Compared to waiting around for an EV’s battery to recharge, hydrogen appeared to be the much more convenient option.
The challenge is that hydrogen is very energy intensive to create as converting the electricity to hydrogen via electrolysis is only 75% efficient. Then the gas has to be compressed, chilled and transported, which loses another 10%. The fuel cell process of converting hydrogen back to electricity is only 60% efficient, after which you have the same 5% loss from driving the vehicle motor as for a BEV. The grand total is a 62% loss in energy – more than three times as much as an electric car.
Nevertheless, hydrogen still has niches where its main strengths – lightness and quick refuelling – give it a clear advantage. While you can fit your personal driving lifestyle around strategic battery charging stops, this is not ideal for commercial vehicles such as trains that need to run for very long periods and distances with only short waits to refuel. The weight of batteries for eight hours of continual usage would also be prohibitive for these vehicles. Therefore, hydrogen could be a viable option, despite the inefficiency.
The post How ‘green’ are electric cars? appeared first on Renewable Energy World.
Source: Renewable Energy