High-Mileage Electric Cars Prove More Durable Than Petrol Models in MOT Study

High-mileage electric vehicles (EVs) demonstrate greater durability than their petrol counterparts, according to a comprehensive study analyzing 47.4 million MOT tests in the UK. The research, commissioned by the British Vehicle Rental and Leasing Association (BVRLA) and conducted by New AutoMotive, indicates that EV failure rates plateau at higher mileages, while those for petrol and diesel vehicles continue to increase.

At lower mileages, between 20,000 and 40,000 miles, the difference in MOT failure rates between electric and petrol cars is minimal, with 12% of EVs failing compared to 11.7% of petrol cars. However, this trend shifts significantly around the 60,000-mile mark. From this point onward, the MOT failure rate for electric cars stabilizes at approximately 16%.

By 120,000 miles, the failure rate for EVs remains around 16%, whereas petrol cars face a failure rate of 23.5%. This gap represents a substantial durability advantage for electric vehicles as they accumulate mileage. For vehicles between three and eight years old with 90,000-120,000 miles, EVs had a 16.5% failure rate compared to 22.1% for petrol and 21.2% for diesel cars.

The study also observed that electric vehicles are more likely to remain on the road. Over a 30-month period, 94.6% of electric cars returned for a subsequent MOT test at 15 years old, compared to 88.1% of petrol cars. This suggests a lower road-exit rate for EVs.

Furthermore, longevity does not appear to be linked to EVs becoming low-mileage second cars. Electric vehicles recorded higher median annual mileages than petrol cars across all examined ages from four to 16 years. For example, at 12 years old, EVs covered a median of approximately 4,920 miles annually, versus 4,410 miles for petrol cars.

Hybrid vehicles also showed strong performance, with some categories recording lower MOT failure rates than either fully electric or petrol models. In one instance, the failure rate for hybrids was 11.8%, compared to 13.5% for EVs and 21.4% for petrol cars.

Despite these findings, the study highlighted specific areas where EVs performed less favorably. Tyre defects were approximately 1.8 times more common on EVs than on petrol cars, a trend particularly noted in earlier EV models adapted from combustion-engine platforms. Regenerative braking also presented a complex picture: while high-mileage EVs showed fewer brake defects, older, low-mileage EVs experienced an increase in friction-brake issues, attributed to corrosion from less frequent use of physical brakes.

A significant observation from the research is the absence of battery health assessments in the standard MOT test. The current MOT process does not evaluate battery state of health, degradation, or charging performance. Researchers emphasize that this battery information should be considered alongside mechanical roadworthiness when evaluating a used EV.

Toby Poston, chief executive of the BVRLA, noted that mileage is a key factor in used car perception, and this data suggests a need to re-evaluate how higher-mileage EVs are viewed. He stated that well-maintained, higher-mileage electric cars can be very durable, which is crucial for making electric vehicles accessible to a wider range of consumers through the used market. Confidence in these vehicles, Poston added, is vital for a healthy and affordable second-hand EV market.