Study shows that UK emissions would fall 12 per cent if everyone drove an EV

Tags: #ev-emissions

We all know that cars contribute a sizeable proportion of the country's carbon dioxide pollution, but assessing just how much isn't an exact science. More to the point, the effect on emissions if everyone switched to EVs overnight hasn't been clear – until now. According to a new academic paper, 12 per cent of UK emissions could be wiped out by switching to electric cars.

The trio, with two from Nottingham Trent University and one from the University of Aberdeen, have published a peer reviewed paper which was put together for last year's International Conference on Energy and Sustainable Futures. Renewed focus has been put on the research in light of the coronavirus shutdown, which has seen a huge improvement in air quality not only here, but across the globe.

As restrictions begin to ease and people default back to their old reliance on the car for... well... everything, researchers George Milev and Amin Al-Habaibeh have published a piece in The Conversation. They asked a simple question: What would the effect on overall UK emissions be if people switched from ICE to EVs overnight?

At present, there are around 39 million cars in the UK and EVs make up a very small percentage of these, but set against the backdrop of ever-tightening automotive emissions restrictions, the Net Zero 2050 ambition and the end of new ICE car sales by 2035, it's important to gain an understanding of the overall benefit.

Emissions from light passenger vehicles – i.e. cars – make up around 18 per cent of the greenhouse gasses per year at present according to government figures. Obviously, at the tailpipe, EVs produce zero emissions so the simple way of doing the maths is very obvious; just remove 18 per cent of total UK emissions from the atmosphere.

Thankfully the research goes deeper than this.

The researchers looked at individual vehicle models of all fuel types, their market share and official emissions figure to get a current scenario. For petrol and diesel, they looked at best sellers such as the Ford Fiesta, Vauxhall Corsa and VW Golf. Where EVs were concerned, they assessed the Nissan LEAF, BMW i3, ZOE and Tesla Model S among others, using each car's kWh/100km and total battery capacity figure to gain an idea of upstream emissions.

Using this methodology, they found that 14 per cent of total UK carbon emissions would be wiped from the country's pollution tally. However, the resulting increase in electricity production required to charge everyone's EV adds two per cent back onto that tally, giving the final 12 per cent reduction in total emissions figure. That equates to 42 million tonnes less of carbon dioxide spewing into the atmosphere.

Limitations of the study

Obviously, using official figures from test cycles is far from representative of a real-world figure – especially for ICE vehicle emissions and fuel consumption. Then there's the impact of making each fuel type. For example, making petrol requires oil to be shipped and transported; it's a hugely mucky business all the way from well to wheel. For EVs, there are the differences in energy production methods where on some days wind might make up almost 50 per cent of UK production, but on others, fossil fuels will make up a greater proportion.

The researchers recognise these limitations and admit that the 12 per cent figure is representative – at best. They do, however, write: “The real environmental benefits would go beyond just reducing emissions. Electric cars would also reduce air pollution, particularly in busy cities, supporting healthier living. By increasing the demand for electricity, they could also promote the development of renewable energy, while cars could even be used as a sort-of ‘collective battery”’ to provide a buffer and balance electricity supply and demand.”

So essentially, the study almost certainly underestimates the benefits of switching to EVs.

Impact of coronavirus on emissions

In an opinion piece about the impact of coronavirus we cited studies that showed emissions around the world had decreased significantly as countries went into lockdown. In China, CO2 dropped by around 25 per cent for January compared to January 2019. But it's not just greenhouse gasses; instances of clean air in cities have sky-rocketed across the world. For the first time in 30 years people in Jalandhar, northern India, have been able to look north and see the Himalayas thanks to the fact they're no longer living in a persistent fug of grotty air. Again in India, residents of New Delhi called the air 'positively Alpine'.

The most recent study we can find by the University of East Anglia and cited in The Independent reckons that emissions have decreased by up to 17 per cent across the globe in April vs. April 2019. That's the equivalent of 17 million tonnes per day and puts April on par with figures for 2006. For the year as a whole, the UEA team think that the total reduction in annual emissions compared to 2019 could be between four and seven per cent depending on when things get back to normal.

However, the researchers from the university don't think the savings will be long lasting. The simple fact is that the reductions are due to a shutdown of existing transport systems, industry and energy generation infrastructure. As soon as it restarts, so does the pollution. If long-term reductions are to be made, such infrastructure would need to be improved and people's habits would need to change significantly.

Against the backdrop of boomeranging emissions post-lockdown, the switch to EVs can't come soon enough.