Car manufacturers are moving to electric vehicles (EVs), but critics say there are hidden environmental costs with EVs.
What’s the truth?
It is often claimed that electric vehicles are environmentally damaging and climate unfriendly because of the environmental costs of manufacturing the electronics and batteries.
This may have been true in the past, and may still be true in some countries. But in most cases now and in the future, electric vehicles will be much less environmentally damaging than combustion vehicles.
The total life cycle environmental costs of motor vehicles needs to be considered in three separate life stages.
Both types of vehicles require mining of metals, manufacturing of components and assembly. Battery manufacture is a major additional component in electric vehicles. All these processes have environmental impacts, including the energy costs and the landscape degradation caused by mining.
Here we need to consider the emission from the vehicle and the environmental cost of producing the fuel (petrol, diesel or electricity).
Included here are the costs of recycling or waste disposal of all components of the vehicle, including battery and electronic components.
It is important to note that the environmental impacts will vary greatly, not just from one model car to another, but from country to country. This is because the generation of electricity and the processes for disposal and recycling can vary greatly.
Also, technology and costs are changing rapidly, so assessments made more than a few years ago are likely to be out of date.
Most components of cars or other vehicles are similar whatever the means of propulsion, so the environmental costs of these are similar. But EVs have significant additional environmental impacts in the manufacture of their large batteries. There are two issues here:
- Lithium batteries that are currently used require a number of “rare earth elements” (e.g. lithium, nickel, cobalt, manganese or graphite) whose mining and refining processes are quite polluting – they can generate acid or radioactive wastes.
- Large amounts of energy are required to produce these large batteries, and that energy may result in significant carbon emissions.
So speaking generally, EVs have a higher environmental cost to produce, although this cost difference is reducing all the time due to:
- As the electricity generation of manufacturing countries shifts from fossil fuels to renewables (or nuclear), the carbon emissions reduce. So the country of manufacture is currently significant.
- Battery technology is improving rapidly, so that manufacture will be less polluting in the future. At present, Lithium Iron Phosphate (LFP) cells provide a less polluting alternative to the commonly used lithium batteries using nickel-cobalt-manganese (NCM) technology. In the future, it is likely there will be a move away from lithium-ion batteries to batteries with more benign materials, such as sodium-ion or zinc-ion cells.
Thus we can expect that the manufacture of EV cars will always have slightly larger environmental impacts than combustion engine vehicles, but the gap is narrowing.
Here electric vehicles shine. If charged from renewable energy sources, their carbon emissions are very small, whereas internal combustion engine (ICE) vehicles have large ongoing emissions (that generally increase as the vehicle ages and runs less efficiently).
Even if the electricity networks used to charge vehicles are fossil-fuel based, EVs generally result in lower carbon emissions. For example, a 2018 study estimated the following CO₂ emissions:
- EV in New Zealand, whose electricity is 84% renewable – emissions of 25 gm of CO₂ per km.
- EV in Australia, with 21% renewable – emissions of 170 gm of CO₂ per km.
- ICE vehicle – emissions of 251 gm of CO₂ per km.
In Europe, similar results have been calculated in a 2017/18 study. There EV’s were calculated to on average cause 60% less emissions than gasoline vehicles and 50% less than diesel. There was significant variation however, with emissions being comparable in several EU countries (Cyprus, Latvia, Estonia, Malta & Poland), while in other countries (Belgium, France, Finland, Sweden) the reduction in emissions was much greater.
As for manufacture, the bulk of recycling/disposal environmental impacts are similar for both types of vehicles, with the major difference being battery recycling. It has been estimated that, overall, EVs may cause about 30% more carbon emissions than ICE vehicles. Improved recycling of batteries can reduce this difference.
EVs generate more emissions in the manufacture and disposal phases while ICE vehicles generate more emissions during the years of use. The question is, how do these emissions balance out?
It seems that the final answer depends on the country and the year of estimation, plus the length of time the car is in use. The latest figures I have found indicate:
Currently, petrol and diesel cars on average emit almost 3 times the carbon over their entire life than do EVs. Reductions with EVs range from 22-28% in some countries to almost 80% in other countries. It is estimated that by 2030, ICE emissions over the entire life cycle would be more than 4 times EV emissions.
An EV starts with a significant emissions deficit compared to an ICE, but makes this up over time because of its lower running emissions. The cumulative emissions from a new EV take 4 years be less than continuing with a current ICE, and 2 years compared to buying a new ICE.
Australia & New Zealand
A few years ago (2018), EVs came out only 18% better in Australia, but 62% better in NZ. However if an EV owner buys “green electricity” and mostly recharges at home, the Australian figures would be much better.
Generally speaking, public transport remains a good option in countries with fossil fuel based electricity. However in countries with a high percentage of renewable energy, only electric buses (and presumably trams and trains) have lower emissions than EVs.
Electric cars are already a more climate friendly option than internal combustion engine cars in Australia and in most first world countries. And the gap will only increase as battery technology improves and electricity grids use more renewable sources.
People saying otherwise are either using old data, cherry-picking their data, or not reflecting the facts.
Transitioning to renewable electricity generation is a priority for Australia.
- Climate explained: the environmental footprint of electric versus fossil cars. The Conversation, 2019.
- Life-cycle emissions of electric cars are fraction of fossil-fuelled vehicles. The Driven, 2020.
- Factcheck: How electric vehicles help to tackle climate change. Carbon Brief, 2019.
- Effects of battery manufacturing on electric vehicle life-cycle greenhouse gas emissions. International Council on Clean Transportation, 2018.
- Lifecycle assessment: Electric cars vs ICEs. Electrive.com, 2020.
- Life cycle environmental and cost comparison of current and future passenger cars under different energy scenarios. B Cox, C Bauer, AM Beltran, DP van Vuuren, CL Mutel. Science Direct, 2020.
Photo: NRMA electric vehicle fast charging station in the Hunter Valley (NRMA).