Traditionally a compromise for electric vehicles, several manufacturers now sell models which can tow. Here’s what you need to know.
Why can only a few electric vehicles tow a trailer?
Some petrol and diesel models also can’t tow. Towing capacity is set during Type Approval, an assessment which all vehicles are put through before they go on sale, but it’s an optional part of that process. If a manufacturer decides that a vehicle is unlikely to pull a trailer – for example, a high-performance supercar or short-range electric vehicle – then they can choose not to approve it for doing so. If a vehicle is sold without this information, then it is illegal to use it for towing [1].
There are some mechanical challenges, too. The instant pulling power of an electric vehicle is arguably better suited to towing than a combustion engine, but the motor also brakes as you lift off the throttle, returning energy to the battery. This could unsettle the trailer and would need to be calibrated to accommodate the extra weight while towing [2]. Particularly as battery packs mean electric vehicles are typically heavier than their petrol or diesel counterparts.
What can you tow with an electric vehicle?
Type Approval will set limits for two types of trailers [3]:
- Unbraked: Trailers without their own braking system. These cannot weigh more than 750kg when fully loaded.
- Braked: Trailers with their own braking system, designed for heavier loads – such as caravans, cars or boats. These cannot weigh more than 3,500kg when fully loaded.
Typically, electric vehicles which are approved for towing can unbraked trailers up to the 750kg weight limit. The capacity for a braked trailer depends on the towing vehicle and its powertrain, but it’s typically lower for an electric vehicle than its fuel-burning equivalent. For example, a diesel BMW X5 can tow braked trailers weighing of up to 3,500kg [4], whereas the electric BMW iX SUV is limited to 2,500kg [5].
Which electric vehicles can tow?
As new models provide longer ranges better suited to touring, there’s a growing choice of electric vehicles now approved for towing. These are as follows:
Maximum trailer weight | ||
Unbraked | Braked | |
Audi e-tron quattro | 750kg | 1,800kg |
Audi Q4 e-tron | 750kg | 1,000-1,200kg* |
BMW i4 | 750kg | 1,600kg |
BMW iX | 750kg | 2,500kg |
BMW iX3 | 750kg | 750kg |
Citroën ë-Berlingo | 750kg | 750kg |
Citroën e-Spacetourer | 750kg | 1,000kg |
Ford Mustang Mach-E | 750kg | 750kg |
Hyundai Ioniq 5 | 750kg | 1,600kg** |
Jaguar I-Pace | 750kg | 750kg |
Kia EV6 | TBC | 1,600kg |
Kia Niro EV | 750kg | 750kg |
Mercedes-Benz EQA | 750kg | 750kg |
Mercedes-Benz EQC | 750kg | 1,800kg |
Mercedes-Benz EQE | 750kg | 750kg |
Mercedes-Benz EQS | 750kg | 750kg |
MG ZS | 500kg | 500kg |
Nissan Ariya | 750kg | 1,500kg |
Peugeot e-Rifter | 750kg | 750kg |
Peugeot e-Traveller | 750kg | 1,000kg |
Polestar 2 | 750kg | 1,500kg |
Skoda Enyaq | 750kg | 1,200-1,400kg* |
Ssangyong Korando EV | 500kg | 1,500kg |
Subaru Volterra | TBC | TBC |
Tesla Model 3 | 750kg | 1,000kg |
Tesla Model X | 750kg | 2,268kg |
Tesla Model Y | 750kg | 1,600kg |
Toyota BZ4x | 750kg | TBC |
Vauxhall Combo-e Life | 750kg | 750kg |
Vauxhall Vivaro-e Life | 750kg | 1,000kg |
Volkswagen ID.4 | 750kg | 1,000kg |
Volvo C40 Recharge | 750kg | 1,500-1,800kg* |
Volvo XC40 Recharge | 750kg | 1,500-1,800kg* |
* Two or four-wheel drive versions
** 73kWh battery only
How does towing affect the range of an electric vehicle?
Similar to a petrol or diesel vehicle, it depends on the weight of the trailer which means this information isn’t included in brochures. However, Audi recently published data from a 500-mile road trip in the United States, using the e-tron electric SUV, which gives some indication of the impact on efficiency.
Towing impact
Driven at a constant 60mph with its maximum 1,800kg trailer load, in the rain and with a relatively cold ambient temperature of 35°F (1.7°C), the vehicle travelled 1.3 miles per kilowatt-hour (kWh) of energy [6]. That’s around half the published WLTP-derived efficiency in Europe [7], and similar to the results of a 2019 test, carried out by the Norsk Elbilforening (Norwegian Electric Vehicle Association) [8].
Charging bay size
Faster charging helps. Audi pointed out that 80% of the e-tron’s range can be replenished in around 30 minutes at an ultra-fast charging point. However, it’s worth bearing in mind that most charging bays are not designed to accommodate a vehicle and trailer, so it might be necessary to unhitch before plugging in. Gridserve’s new Electric Forecourt facilities are among first to include spaces big enough for larger vehicles and tow cars [9].
REFERENCES:
[1] Department for Transport. (n.d.). Towing with a car. [online] Available at: https://www.gov.uk/towing-with-car/weight-and-width-limits. [Accessed 11 May. 2022].
[2] RAC. (n.d.). Can electric cars tow? A guide and tips for caravans. [online] Available at: https://www.rac.co.uk/drive/electric-cars/running/electric-cars-tow [Accessed 11 May. 2022].
[3] Department for Transport. (2016). Towing a trailer with a car or van: the basics. [online] Available at: https://www.gov.uk/government/publications/towing-a-trailer-with-a-car-or-van/towing-a-trailer-with-a-car-or-van-the-basics [Accessed 11 May. 2022].
[4] BMW (2021). Specifications. BMW X5. [online] Available at: https://www.press.bmwgroup.com/global/article/attachment/T0326836EN/472818 [Accessed 11 May. 2022].
[5] BMW (2021). Technical Specifications. BMW iX. [online] Available at: https://www.press.bmwgroup.com/global/article/attachment/T0333569EN/486247 [Accessed 11 May. 2022].
[6] Audi Newsroom (2020) Audi e-tron brings the first modern electric vehicle to ‘Fully Charged LIVE’. [online] Available at: https://media.audiusa.com/en-us/releases/390 [Accessed 11 May. 2022].
[7] Audi (n.d.). Audi e-tron. [online] Available at: https://www.audi.com/en/experience-audi/models-and-technology/production-models/e-tron.html. [Accessed 11 May. 2022].
[8] elbil.no. (n.d.). The very first test of three electric cars with caravans. [online] Available at: https://elbil.no/the-very-first-test-of-three-electric-cars-with-caravans/ [Accessed 11 May. 2022].
[9] Gridserve (2020). Braintree Overview. [online] Available at: https://www.gridserve.com/braintree-overview/ [Accessed 11 May. 2022].