Electric vehicles (EVs) are crucial to achieving the world’s climate change targets. They play a significant role in mitigation strategies that keep warming far below 2C or 1.5C, which would be in line with the goals of the Paris Agreement.
While EVs don’t directly contribute to greenhouse gas emissions, the power they utilize is still mostly generated from fossil fuels in many areas of the globe. The creation of the vehicle, and particularly the battery, requires the usage of energy.
Here, Carbon Brief offers a thorough examination of the effects of EVs on the environment in reaction to recent false media stories on the subject. Carbon Brief’s study reveals the following:
- In all of Europe, EVs produce far less pollution over the course of their lifespan than traditional (internal combustion engine) automobiles.
- The advantages of EVs are less significant and their lifetime emissions may be comparable to those of the most effective conventional cars, including hybrid-electric versions, in nations where coal-intensive energy production is common.
- However, driving emissions for current EVs and manufacturing emissions for future EVs will decrease as nations decarbonize electrical generation to reach their climate commitments.
- Even before taking into account the declining carbon intensity of electricity production over the course of the vehicle’s lifespan, driving a Nissan Leaf EV in the UK in 2019 resulted in lifetime emissions per kilometer that were nearly three times lower than those of the typical conventional automobile.
- It might be difficult to compare electric and conventional automobiles. They are influenced by a variety of factors, including the size of the cars, the accuracy of the fuel-economy calculations employed, the methodology used to compute electricity emissions, the driving patterns expected, and even the local weather conditions. No single estimate can be used everywhere.
Different research provides wildly varying values for electric car battery emissions. As battery costs decrease and car manufacturers include bigger batteries with greater ranges, battery manufacturing emissions may reduce electric vehicle climate advantages.
Half of the battery emissions originate from the power required in manufacturing and assembly. Producing batteries in places with low-carbon electricity or in renewable-energy plants may cut battery emissions, as will be the case with the best-selling Tesla Model 3.
Problematic fuel economy estimates
The ifo research shows the dangers of adopting test-cycle fuel efficiency instead of real-world performance. The research contrasted Mercedes C 220 with Tesla Model 3 lifetime emissions, including manufacturing emissions. Tesla’s lifetime emissions were 90% to 125% of the Mercedes’.
EVs varied from somewhat better to considerably worse than diesel vehicles, according to ifo.
The research assumed a Mercedes fuel efficiency of 52 mpg, which is higher than the typical US automobile (25mpg for petrol cars) but comparable to the UK (52mpg for petrol vehicles and 61mpg for diesel vehicles). Various fuel-efficiency tests get different findings.
The New European Driving Cycle (NEDC) ratings used in the EU overstate real vehicle fuel efficiency by up to 50%, and maybe more for Mercedes automobiles.
The study’s anticipated Tesla Model 3 energy usage (241 watt-hours/mile) is only 8% lower than EPA real-world estimations (260 watt-hours/mile). Using more accurate fuel efficiency estimates for the conventional car would change the ifo analysis, making the EV alternative preferable.
Large differences in battery emissions
Both the ifo research and the ICCT analysis use the same estimate of battery production emissions: a 2017 Swedish ERI study (IVL). IVL analyzed research published between 2010 and 2016 and found that battery production emits 150 to 200 kg CO2 per kWh of battery capacity.
IVL studied battery manufacture in Asia more than in the US or Europe. The IVL research found that battery technology is improving quickly and manufacturing emissions may be reduced.
The IVL study had a major change late in 2019. IVL researchers estimate battery production emissions at 61 to 106 kg CO2-equivalent per kWh, with a maximum of 146 kg. The low estimate of 61 kg is for zero-carbon battery production energy. IVL indicates that new data for cell manufacture, particularly more accurate energy usage measurements for commercial-scale battery plants, drove this modification.
Carbon Brief reviewed published estimates of battery manufacturing’s lifecycle emissions. The graph below displays 17 research, including seven published after the 2017 IVL estimate. It splits research by where the batteries were made: Asia (red), Europe (light blue), the US (dark blue), and numerous areas (grey).
How and when electricity is generated matters
The climatic benefits of EVs depend not only on the nation in which they are employed but also on the area of that nation. In the US, for instance, there are many different ways that power is produced, with the center of the nation having far dirtier electricity than states like California or New York.
It’s also crucial to understand how emissions from power production are calculated. The average emissions from power production are used in numerous assessments, including some that came before this one, although Michalek warns Carbon Brief that doing so may lead to certain conclusions that are not entirely accurate.
Their findings are shown in the image below. The most fuel-efficient gasoline car, a Toyota Prius, is contrasted with two plug-in electric hybrid vehicles, a Chevrolet Volt and a Toyota Prius Plug-in Hybrid, as well as one totally electric vehicle, a Nissan Leaf, in the left column. The same study is shown in the right column for a Mazda 3, a typical conventional car of the same size. Each county in the nation is given a red color if gasoline vehicles have fewer emissions, and a blue color if electric vehicles do.
Electric vehicles ‘not a panacea’ without decarbonization
Compared to the typical conventional car, EVs significantly lower lifespan greenhouse gas emissions in both the US and Europe. This has been a recurring conclusion in the vast majority of research that Carbon Brief has looked at.
Electric cars will almost always be superior to all conventional vehicles as power production becomes less carbon heavy, especially at the margin. There are inherent limits to how efficient gasoline and diesel cars can become, but EV manufacturing emissions and practically all energy usage emissions can be reduced to a large extent thanks to low-carbon electricity and improved battery manufacturing efficiency.
One of the main mitigation strategies for limiting warming to achieve the goals of the Paris Agreement is the switch from traditional gasoline and diesel automobiles to electric vehicles (EVs). For it to be successful, power production must rapidly decarbonize. Electric cars will still be far from reaching “zero emissions” if nations do not replace coal and, to a lesser degree, gas.