Winter has a way of cutting through marketing claims like road salt through sheetmetal. Range estimates, charging promises, efficiency bragging rights—none of it is immune once temperatures drop and heaters switch on. A recent Green NCAP study puts that reality into sharp focus, comparing how electric vehicles and gasoline-powered cars cope when the weather turns unfriendly. The results aren’t shocking, but they are clarifying.
The test lined up two EVs—the BYD Sealion 7 and the Cupra Born—against two familiar internal-combustion benchmarks, the BMW 5 Series and BMW X2. Same cold conditions, same real-world scrutiny. Different outcomes.
Big Battery, Smaller Losses
The BYD Sealion 7 Comfort entered the test with the usual EV disadvantages: size, weight, and a lot of mass to keep warm. At 2,225 kilograms and packing an 82.5-kWh battery, it’s no lightweight. Yet it handled winter better than expected.
In warm conditions, the Sealion 7 manages around 400 kilometers of range. In the cold, that figure dropped to 337 kilometers—a loss of roughly 16 percent. Green NCAP calls that “relatively moderate,” and in EV terms, that’s practically a compliment. Credit goes to effective thermal insulation and the ability to preheat the cabin before driving, reducing the battery drain once underway.
Charging, however, tells a less flattering story. BYD promises a 10-to-80 percent fast charge in 32 minutes. Reality added about eight more minutes, enough to earn a “poor” rating in this category. Still, the Sealion 7 walked away with a four-star sustainability score and 73 percent overall—solid numbers for a large electric SUV.
Smaller EV, Bigger Winter Penalty
The Cupra Born didn’t fare as well. Lighter at 1,839 kilograms and running a smaller 60-kWh battery, the Born should have had an efficiency edge. Instead, winter hit it harder.
From a warm-weather range of 328 kilometers, the Born dropped to just 221 kilometers in cold conditions—a 33 percent reduction. That’s the kind of number that turns a casual road trip into a charging strategy session.
There was a bright spot. Green NCAP praised the accuracy of Cupra’s energy-consumption readings. Drivers see what the car is actually using, not an optimistic guess. BYD, by contrast, showed discrepancies in its consumption data, prompting a recommendation for a software update to deliver clearer, more reliable information.
Gas Cars: Predictable, Not Perfect
On the gasoline side, the BMW 5 Series and X2 behaved exactly as you’d expect. Fuel consumption went up in winter, but not dramatically—and certainly not catastrophically.
The 5 Series increased from 6.8 to 8.1 l/100 km, while the X2 rose from 7.1 to 8.0 l/100 km. The reason is simple: internal-combustion engines generate waste heat, which conveniently warms the cabin. Efficiency suffers a bit, but range anxiety never enters the conversation.
Green NCAP notes that these increases are modest and predictable, giving gasoline cars an edge in real-world confidence when temperatures plunge.
The Real Takeaway
From an environmental standpoint, the EVs still score well. The Sealion 7 and Cupra Born remain attractive options, especially for drivers who mostly stick to shorter trips. But winter exposes the weak points: range loss, longer charging times, and the added complication of a fast-charging network that still isn’t where it needs to be.
Long journeys in an EV during cold weather demand planning, patience, and a willingness to accept that official figures are more suggestion than guarantee.
Green NCAP’s message is clear. Electric-car manufacturers need better thermal management systems and greater transparency about cold-weather performance. Because nothing kills enthusiasm faster than a buyer who feels misled—especially when the temperature drops, the range shrinks, and the real-world numbers suddenly have very little to do with what was promised on paper.
Source: Green NCAP; Photo: Shutterstock