Are EVs really better for the environment?

Almost all car-makers are now producing electric vehicles and many have already announced end dates for the production of traditional internal combustion-engined (ICE) vehicles.

EVs are coming, whether you like it or not, but given they produce more CO2 than ICE vehicles in terms of raw materials production and manufacturing, how long does it take for an EV’s total carbon footprint to be lower than an equivalent conventional model’s?

When it comes to lifecycle CO2 emissions – including driving and all manufacturing, starting with the production of raw materials (previously referred to as ‘well-to-wheel’ emissions) – it’s difficult to draw comparisons between electric and combustion vehicles with any consistency.

Unless the vehicles in question are built by companies with identical upstream supply chains and the same manufacturing process and scale, and an identical energy source is employed for their production and distribution logistics, it’s impossible to make a valid comparison.

And that’s before you consider ‘in-use’ emissions while driving.

Fuel consumption is the main running cost and primary CO2 source for an ICE vehicle once it’s on the road. But EVs introduce other factors such as energy consumption, the type of power used to charge its battery, the service life of that battery in addition to the vehicle itself, and exactly how they are disposed of at the end of their lives.

However, Volvo’s recent lifetime CO2 analysis of its own comparable petrol and electric vehicles appears to offer the most accurate CO2 emissions comparison between ICE and EV to date.

Volvo’s 2020 Carbon Footprint report, which compares the battery-electric XC40 Recharge EV with the petrol-powered XC40 ICE, confirms that CO2 emissions from the materials production and refining component of the manufacturing process is in fact higher for the electric vehicle.

This would be a bad thing if we all bought EVs and then just parked them. But the study also confirms the more relevant point: during the EV’s usage cycle, it not only makes up for the extra CO2 emitted during production of its raw materials and batteries, but can discount it entirely – even when recharging using ‘dirty’ electricity.

Volvo’s Carbon Footprint study involved ICE and EV versions of the Volvo XC40, both built at the same factory, and subjected them to Life Cycle Assessment (LCA) according to ISO LCA standards.

While the report was guided by the ‘Product Life Cycle Accounting and Reporting Standard’ published by the Greenhouse Gas Protocol, Volvo notes that this Standard only “provide[s] guidelines for the practitioner”.

As a consequence, Volvo suggests that other vehicle manufacturers’ Carbon Footprints may not be directly comparable, and that: “In general, assumptions [in this report] have been made in a conservative way, in order to not underestimate the impact from unknown data”.

Because the XC40s are identical except for requirements associated with their powertrain and built by the same company in the same factory, with many of the same suppliers, that markedly reduced the number of variables in the CO2 comparison.

The measurement of carbon dioxide used here is Co2e. Greenhouse gases are often quantified as mass unit of CO2e, where e is short for equivalents, such as methane (CH4), nitrous oxide (N2O) and freons/CFCs.

The upshot of this report is that in terms of total manufacturing emissions, the EV version of the XC40 produces 25.4 tonnes of CO2e versus the ICE model’s 16.1 tonnes.

Dissecting these totals, the XC40 ICE’s raw materials production and refining creates 14 tonnes of CO2e (XC40 EV: 17 tonnes), while for the actual vehicle manufacturing process by Volvo, the ICE produced 2.1 tonnes versus the EV’s 1.4 tonnes.

The emissions from the EV’s lithium-ion battery production, calculated separately to raw materials production, adds a further seven tonnes of CO2e to its manufacturing tally.

These figures show that the XC40 EV is friendlier to the environment when it’s actually being built, but generates a bigger carbon footprint before it arrives at the factory, in terms of raw materials and battery production.

Materials production and refining is higher for the EV mainly because the XC40 Recharge is heavier (2170kg versus 1690kg) and has a larger share of aluminium and weight of electronics.

End-of-life CO2e emissions including recycling were similar, with 0.6 tonnes of CO2e for the ICE and 0.5 tonnes for the EV.

While Volvo’s end-of-life calculations included disassembly, shredding of components and either sending them to landfill or incinerating (combustible) materials, it assumed that the Li-ion battery is recycled.

That assumption kicks the can down the road, as it doesn’t attach any meaningful carbon cost to dealing with the battery once it’s reached its use-by date in an EV.

According to the International Energy Agency’s Global EV Outlook 2020: “Battery reuse in second-life, stationary storage applications… can extend the lifetime of batteries that are no longer suited for automotive applications…

“However, there is little experience to date from this nascent market.”

The key here is that it is a nascent market. Volvo can’t predict what the carbon cost is for a recycled battery when the quickly developing market has yet to be fully established.

This rapid evolution occurring in EV battery recycling was noted by the IEA in its 2020 report: “…the number of [second-life applications for EV batteries] projects is increasing dramatically in the past 3 years… almost all the major automotive OEMs have launched or planned to launch second-life application projects, either working with their battery supplier or employing a third-party company…”

Regardless of this unknown, even in a worst-case scenario, Volvo’s study calculates that the electric version of the XC40 produces less CO2e over its lifecycle than the ICE version. ‘Lifecycle’ in this report means up to 200,000km.

The XC40 Recharge EV produces 28 tonnes of CO2e in 200,000km of use versus the XC40 ICE at 41 tonnes.

Therefore, in this scenario, the EV would break even (making up for its higher raw materials and battery CO2e) with the ICE vehicle at 146,000km – or almost three-quarters of Volvo’s lifecycle.

This calculation assumes that the EV is driven in a country that uses a global averaged electricity mix (GAEM), which is more carbon-intensive in its production (such as coal-fired power stations) than in regions such as Europe.

Volvo also crunched the numbers using renewable wind turbine energy instead, in which case the XC40 Recharge produces 18 tonnes of CO2e – 10 tonnes less than its ICE equivalent.

So the EV would start to emit less CO2e overall than the ICE vehicle in this scenario after just 47,000km of use.

Therefore, given Australia’s energy mix is closer to the GAEM than 100 per cent wind-powered, based on average annual mileage of 15,000km the Volvo XC40 Recharge’s lifecycle CO2 emissions become lower than its ICE equivalent in just under a decade of ownership.

Volvo point out that the efficiency of EV manufacturing processes is still developing, so a future comparison between ICE and BEV CO2e emissions may look very different.

“The BEV driveline technology is still young compared to the ICE driveline, implying a relatively higher potential of improvements,” it said.

“Recent studies have shown a general decrease in carbon footprint of battery production over recent years, and it is a probable expectation that it will continue decreasing in the future.”

The upshot is that, quite apart from urban air quality, an EV’s impact on the environment becomes less than that of an equivalent ICE well within its lifecycle.

And the further the EV is driven – and the ‘greener’ the energy it’s charged with – the greater its environmental advantages, which will also be accelerated by advances in EV technologies.

The biggest tech change will need to occur in raw material and battery production, because that’s where EVs are much more carbon-intensive than ICE vehicles.

Promising to release a similar Carbon Footprint report on all of its new models going forward, Volvo says it’s committed to reducing the lifecycle CO2 output of its vehicle range by 40 per cent between 2018 and 2025, on its way to becoming a climate-neutral company by 2040 – and it’s not alone in that endeavour.