A streamlined EV ‘eco-score’ would encourage green, made-in-Europe electric cars

Lucien Mathieu — April 24, 2024

By setting up a framework to foster resource, climate and energy efficiency in EVs, the EU can reduce the impact of cars beyond tailpipe emissions


The (eco) score approach would simplify the complex approach of full lifecycle analyses of cars, focusing on a narrower scope covering a majority of the EV environmental impact, notably where important technical improvements are possible and need to be encouraged.

By Lucien Mathieu, Cars Director at Transport & Environment, Jean-Philippe Hermine, Managing Director of Institut Mobilités en Transition, and Robin Loos, Senior Sustainable Transport Officer, Deputy Head of Sustainability at BEUC. The three organisations have published a new proposal for a European environmental score for EVs.

Electric cars are one of the best and most effective solutions we have to fight the climate crisis. But they come in all shapes and sizes. Take, for example, the small Dacia Spring in comparison to the hefty Audi Q8 e-tron: the latter carries four times more battery, consumes twice the energy per kilometre driven and carries an additional 2 tonnes in weight.

In March 2023, the EU greenlit its revised car CO2 regulation, a pivotal step in the transition from polluting combustion cars to electric vehicles (EVs). While this regulation propels the industry towards a cleaner future, it is not designed to distinguish between EVs, categorising them all simply as zero-emission.

This creates a gap in today’s regulatory landscape which is leading to a patchwork of national rules – such as the French eco-bonus – risking confusion and regulatory inefficiency. It’s time for the EU to set clear rules and standards for evaluating the environmental performance of EVs.

Growing car size and shift to EVs poses new decarbonisation challenges

While EVs completely eliminate tailpipe emissions, the shift towards an all-electric future accentuates the importance of better managing vehicle size, weight, and material impact. Between 50% and 60% of electric car life-cycle emissions are tied to vehicle production, compared to only around 10% for combustion cars [1].

Today just over half (54%) of new vehicle sales in Europe are SUVs, and this trend shows no sign of slowing down. Larger vehicles mean bigger batteries, making electric cars less affordable, more energy consuming and resource intensive. [2]

The shift in the CO2 emissions hotspot from vehicle use to embedded production emissions and the continuing trend towards SUVs poses new challenges to our decarbonisation efforts. To counter this, policymakers must consider not just tailpipe emissions but also the broader decarbonisation of car production materials and processes as well as curbing the trend towards oversized EVs.

Our aim here is clear: set up a framework to reduce the impact of cars beyond tailpipe emissions by fostering resource, climate, and energy efficiency in EVs.

To achieve this, the next European Commission must set up the methodology and framework for an environmental score for EVs.

Why energy efficiency thresholds alone aren’t enough

Focusing solely on the energy consumption of EVs (measured in kWh/km), as is proposed by the new car CO2 law [3], overlooks other critical factors and would be a missed opportunity as it would fail to put in place comprehensive and future proof rules.

Electric cars with the same battery size can have vastly different energy efficiencies. For example the Tesla Model 3 Long Range has a battery of 78 kWh and an efficiency of 14 kWh/100 km while the Mustang Mach-E has a slightly smaller battery of 75 kWh but consumes much more energy (a whopping 19.6 kWh/100 km). Furthermore, the correlation between vehicle weight and energy efficiency is not very pronounced for EVs, unlike for combustion cars where it is very strong.

An efficiency-centric approach favours improved aerodynamics and may inadvertently favour longer cars over smaller cars since the latter are not very aerodynamic with their box-like shape. A stark illustration of this is the Mercedes-Benz’s Vision EQXX which has a 100 kWh battery pack, weighs 1,800 kg, measures 5 metres long, but reaches an astonishing 8.3 kWh/100 km.

Why lifecycle emission methodology is not the right approach

The European Commission is also tasked with developing a methodology for lifecycle analysis of cars. While lifecycle emissions analyses are crucial for comparing generic vehicle types or categories, it is considered too complex, and impractical for assessing and comparing individual vehicle models. Such an approach would place a heavy burden on the regulators for monitoring, verifying and controlling but also crucially on carmakers who would need to provide detailed information for each material and component and thus undertake complex and detailed assessments of their whole supply chains.

Instead, the proposed score approach would simplify the complex approach of full lifecycle analyses of cars, focusing on a narrower scope covering a majority of the EV environmental impact, notably where important technical improvements are possible and need to be encouraged. Our approach is pragmatic, focused, relies on a simple methodology, can be implemented rapidly and is impact oriented. Additionally, it offers a simplified approach to addressing embedded carbon emissions by potentially replacing specific requirements concerning the carbon footprint of various components, such as battery emissions or the adoption of green steel and aluminium.

The proposed eco-score approach: combining energy efficiency and material carbon footprint

Together, batteries, steel and aluminium account for 70%-75% of the embedded carbon footprint of electric cars, the rest being mainly plastics, the motor and electronics. The good news is that the EU already has rules for the evaluation of the carbon footprint of these components thanks to the Batteries Regulation and CBAM rules [4].

Our proposed metric, or eco-score, combines both the energy efficiency (in kWh/km) and carbon footprint at the vehicle’s production stage from the battery, steel and aluminium (in kgCO2e).

Such an eco-score surpasses a limited focus on efficiency, embracing a more holistic environmental performance evaluation that considers the climate footprint of the EV. It provides manufacturers the flexibility to comply with targets by encouraging improvements in vehicle efficiency, the use of low carbon batteries, steel or aluminium, and/or the adoption of smaller vehicles or battery sizes. This allows manufacturers room to meet targets in a way that best suits their respective strategies across their entire new car fleet.

Crucially, it provides much needed information for consumers to assess and compare the environmental performance of EVs. This can be addressed via the expected review of the Car Labelling Directive. The eco-score supports consumers beyond just providing robust information as it promotes small, affordable EVs which are a double win – both for climate and consumers’ wallets.

For illustration we compared the eco-score of a typical small electric car with a typical large electric car [5]. In our example, this typical small EV produced in Europe achieves an eco-score of 726, while the same vehicle produced in China has a score of 1,242 or around 70% worse (the lower the score, the better the environmental performance). Similarly, a large EV produced in Europe has a score of 1,324, while its equivalent produced in China has a score of 2,209.

Considering the current influx of cheap Chinese EV imports, these environmental rules can be an additional tool in the EU’s green industrial policy toolbox. By factoring in the carbon footprint of steel and aluminium, the rules would indirectly support European EV production, which relies on cleaner steel and aluminium than in most other regions, including Asia.

In short, setting environmental standards for EVs is not just a regulatory and climate necessity; it’s a roadmap to support the continuous transformation of the automotive industry on the basis of a fair, green, and harmonised level playing field.

This is the opportunity for the EU to lead the charge in crafting a new framework to make EVs fit for the future and lower the material and energy footprint of the future all-electric car system.


[1] T&E EV lifecycle analysis: transenv.eu/LCA. EU average and medium car.

[2] T&E’s Clean and Lean report and IDDRI study on material demand for EVs show that smaller batteries would be the measure with the single greatest impact – resulting in up to a quarter reduction in raw materials across the scenarios.

[3] The 2023 Car CO2 law requires the European Commission to assess the impacts of establishing minimum energy efficiency thresholds for electric vehicles (recital 19 and article 15).

[4] The delegated act for the calculation of the carbon footprint of batteries is still being finalised, but the information on the total carbon footprint of the battery (in kgCO2e) would be available.

[5] The small car is based on a typical B segment EV like the Peugeot e208 or the Citroen eC3 (45 kWh, 1600 kg, efficiency of 15 kWh/100km). The large car is based on a typical D segment EV as the Tesla Model Y (80 kWh, 2,000 kg, 17 kWh/100km). The assumption and emissions factors are based on the methodology from the French government for the calculation of the carbon footprint of EV as part of the new eco-bonus.

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