Note: This advice is given by the CAP Executive about non-broadcast advertising. It does not constitute legal advice. It does not bind CAP, CAP advisory panels or the Advertising Standards Authority.


In 2021 and 2022 the ASA and CAP undertook a Climate Change and the Environment (CCE) project taking stock of the rules regulating environmental claims.  This project consisted of three concurrent strands:

  • Proactive regulation: proactively looking at environmental claims in several priority areas with a view to updating our position on emerging and existing themes and taking action against advertisers who use green claims in a way that is likely to mislead or cause harm. 
  • Standards fit for the 2020s: taking stock of how effective our rules and guidance are in governing environmental claims. 
  • Knowledge, education and communication: updating our existing resources to make them easily accessible, and creating new training materials and other educational resources to improve industry’s understanding and overall compliance with our rules on misleading and harmful environmental claims.

While this advice represents the current position, the ASA’s CCE project is now reviewing our approach to these issues, which may lead to further rulings and updates to this guidance.

With an increase in the number of electric and hybrid vehicles available to consumers, increasing competitiveness in the market and statutory targets for emissions the ASA has seen a rise in the number of complaints about the marketing of such vehicles, particularly in terms of claims around their environmental impact.

This guidance gives an overview of some key considerations in terms of advertising fully electric or hybrid vehicles, and links to more detailed guidance on some issues.

Many complaints relate to the claimed efficiency of the vehicle: the claimed miles per gallon a plug-in hybrid vehicle can achieve, or the emissions released (either directly or indirectly, through the production of fuel), for example.

Marketers should bear in mind that advertising which highlights a vehicle’s technology, such as the way in which a particular type of hybrid vehicle operates or the charging infrastructure for electric vehicles, should always be designed to be clearly understood by consumers.

Emissions while driving

Absolute environmental claims

Clarity about terminology and technology

Charging times

Fuel consumption, emissions and range figures

Zero emissions claims

Emissions while driving

While advertisers are likely to be able to demonstrate the environmental benefit of using an electric vehicle compared with a petrol or diesel alternative, particularly in terms of localised emissions and the effect on air quality, they should make sure their claims do not overreach.

An ad for Hyundai’s hydrogen fuel cell powered electric SUV, the NEXO, was considered misleading when the ASA investigated a complaint in 2021.

Text on Hyundai’s website included “Introducing the next generation of fuel cell vehicles: All-New NEXO. A car so beautifully clean, it purifies the air as it goes”. Hyundai explained that the NEXO’s fuel cell produced electricity by combining oxygen and hydrogen. A supply of clean air was essential to provide this oxygen, and the system therefore acted to filter air and removing fine dust and gases. Purified air was then expelled from the system.

The ASA considered that the claim “a car so beautifully clean, it purifies the air as it goes” would be understood to mean that the car, overall, had negligible environmental impact, and that it would remove impurities from the air as it was driven meaning that no impurities caused by driving would remain in the air.

While accepting that the NEXO’s systems would purify and remove harmful particles from the air as the car was driving, the ASA noted that particulates from brake and tyre wear would still be released from the car, and these might not necessarily be removed by the car’s filtration system. It considered, therefore, that the headline claim had not been adequately substantiated and was likely to mislead. While this ruling relates to an, at present, rare type of electric vehicle, the principle would apply to advertising of any EV (Hyundai Motor UK Ltd, 9 June 2021) and, therefore, absolute claims that a vehicle has zero or negligible environmental impact should be avoided unless comprehensive substantiation is held.

Absolute environmental claims

It’s not just advertising for cars that risks misleading consumers about the environmental impact of transportation. An ad for an e-scooter which said ““be environmentally... friendly take a TIER” was ruled to misleadingly imply that the scooters caused no environmental damage whatsoever.

The advertiser said that the claim was intended to be implicitly relative, aimed at people who had a selection of travel options available to them, such as petrol cars, or non-electric buses. They provided evidence to support this interpretation, which they said demonstrated the relative lack of negative environmental impact from using an electric scooter as opposed to another means of transport.

The ASA considered that the claim would be interpreted as an absolute claim that the scooter would cause no environmental damage at all throughout its lifecycle. The advertisers evidence showed that the production method would result in emissions and some negative effect on the environment, and the ASA therefore considered the ad to be misleading. (TIER Operations Ltd, 6 April 2022).

Clarity about the terminology and technology

Two ads, about vehicles powered by Nissan’s ePower petrol/electric system were ruled to be misleading because the nature of the cars’ power source was not made sufficiently clear, and the precedent set by this ruling would apply equally to non-broadcast media. 

These TV ads showed sparks being thrown off an electrical transmission tower and following the car shown, along with a voiceover said “Who said electrification can’t spark excitement when unplugged?”. Onscreen text said “FUELLED BY PETROL DRIVEN BY ELECTRIC”, “NO NEED TO PLUG IN” and “New Nissan Qashqai with e-POWER. A unique electrified experience, unplugged”.  Nissan explained that the cars’ wheels were powered purely by an electric motor, which in turn was charged,  directly or indirectly, by a petrol engine, as well as through the cars’ regenerative breaking systems. The ASA considered that the ads placed strong emphasis on electricity as a means of power and the reference to “e-Power” could be understood as meaning that the cars a new, electric technology, acting in the same way as purely electrically powered vehicles that did not require the car to be plugged in was being offered.

The ASA concluded that the ads were misleading and highlighted that similar claims in future should clearly explain the nature of the vehicle’s power source.

More generally, the ruling also highlights that the focus on the cars’ use of electricity would be understood as suggesting the cars were a better choice for the environment than more traditionally powered vehicles. The fact that petrol was needed to indirectly power the car was seen as material information relevant to a consumer’s understanding of this claim and, given that the ASA considered the ads did not make sufficiently clear that the cars did require petrol, they were also ruled misleading on this point. As such, advertisers should take care to ensure that the overall impression of an ad does not exaggerate or mislead about a car’s environmental impact, whether relative to alternative products or as an absolute claim (Nissan Motor (GB) Ltd, 18 October 2023).

An ad describing a car as a “self-charging hybrid”, however, was not upheld as the ASA considered the ad was unlikely to mislead consumers.

The complainant objected that the claim “self-charging hybrid” was misleading because they believed it misrepresented the way in which the electric battery was recharged by using the petrol engine.

The advertiser explained that claim “self-charging hybrid” was intended to refer to the overall vehicle being self-charging, rather than the battery or any other individual component. They believed that consumers would be aware that a hybrid vehicle was powered through a combination of petrol and electricity.

The ASA agreed that the word “hybrid”, in a motoring context, was likely to be interpreted by consumers to mean that a vehicle was powered by a combination of a petrol/diesel engine and a re-chargeable electric battery. The ruling notes that there was no implication that the battery was charged via plugging in. It concluded that the claim “self-charging hybrid” was likely to be understood to mean that the internal mechanics of the car would charge the electric battery (Toyota GB plc t/a Lexus, 13 November 2019).

Charging times

Claims about how quickly an electric or plug-in hybrid vehicle can be charged are becoming more prominent in advertising, and the ASA has investigated whether some of these gave a misleading impression of how long a charge might take, or how easy it was to achieve the fastest charging times featured.

A website promoting an electric SUV which included the claim “…use rapid public charging to reach 80% charge in around 30 minutes* with a 150kW fast-charging system” was investigated by the ASA in 2023. Further down beneath this claim, under the subheading “Rapid charging” was the text “You can easily find rapid charging points in a number of public locations. These highly efficient units are able to recharge 80% of your Toyota bZ4X battery in approximately 30 minutes*”. The asterisk from both claims linked to a qualification which read “Charging times subject to local circumstance. Rapid charging power rates can vary by location.”

The ASA considered the claims presented here were misleading. It noted that the meaning of “local circumstance” was unclear, and that the ad did not highlight the various real-world factors likely to affect how quickly and efficiently a car’s battery could be charged (such as battery or ambient temperature, age and condition of the battery). It also considered the use of wording such as ‘easily find’ suggested that it was relatively straightforward to access 150kW chargers throughout the UK – whereas the ASA understood that provision varied widely throughout the country, and at the time the ad appeared none were available in Northern Ireland (Toyota (GB) plc, 28 June 2023).

The ASA also investigated whether a video on demand ad which included the claim “Charge in approx. 31 minutes” followed by “Max range up to 330 miles” was misleading. Below the first headline claim, text stated “10-80%, 350kWh charger (limited in UK: motorways only, not available in NI, most of Sco/Wal). Test data for comparison – actual times vary (depending on e.g. spec, battery/charger condition & temp.). Longer in cold weather”. Below the second, additional text clarified which model this range figure applied to and stated “May not reflect real life driving results”.

While the advertiser defended the ad by saying that they considered consumers would understand the two claims (the fastest charging time, and the maximum miles of range) to be separate, and not necessarily achievable at the same time, the ruling highlights that they were prominently displayed and presented closely together.

The ASA considered that the overall message of the ad, how each of these headline figures could be achieved and the fact that they were unlikely to be achieved simultaneously was ambiguous. Marketers are advised, therefore, to consider carefully how they present different claims about technical aspects of a car’s efficiency and performance together, and ensure the meaning is clear (Volkswagen Group United Kingdom Ltd t/a Audi, 6 March 2024).

Fuel consumption, emissions and range figures

The requirement to display fuel consumption ('mpg') and CO2 emissions figures in car ads is not a specific requirement of the CAP Code: these and electric driving range figures for electric vehicles and some hybrids must reflect statutory testing regimes. However, advertisers must present these figures in a way which does not mislead, and which makes clear any limitations or conditions on achieving them. More information can be found in Motoring: Fuel consumption, emissions and range figures.

Zero emissions claims

Claims such as “zero emissions” are likely to be acceptable in ads for purely electrically-powered vehicles providing it is made immediately clear that this applies only while driving, and relates only to the lack of resultant emissions from the powertrain as it drives the car. It is important, however, to avoid suggesting that no emissions result from using a vehicle at all.  More information about this can be found in Motoring: Zero emissions claims.

See also Motoring: General environmental claimsEnvironmental: General “Green” claims and Advertising Guidance: misleading environmental claims and social responsibility


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