Ford tests improved electric efficiency with surface heaters in EVs

As part of the EU project CEVOLVER (Connected Electric Vehicle Optimized for Life, Value, Efficiency, and Range), Ford engineers have shown that heating surfaces can reduce energy consumption in the interior of an electric vehicle by 13%.

This can improve the range of that vehicle by 5%. The test was conducted in an electric delivery vehicle. Engineers equipped an E-Transit with heated armrests, floor mats, door panels, sun visors, and a heated steering wheel for practical tests.

Simulating a courier’s day

The test area was mainly roads in and around Cologne and took place in winter and summer, on dry and wet roads, and in heavy rain and wind. The test included the operational profiles ‘parcel deliveries’, ‘general cargo deliveries’, and a one-day ‘tradesman job’ 350 kilometers away.

The testers had to open and close the vehicle doors hundreds of times, realistically simulating the typical working day of a courier driver and tradesman, Ford says. Air heated by an electric heater fan is quickly lost when the vehicle’s doors or windows are opened. The cold air that flows in must first be reheated, which costs energy.

The heated surfaces, however, come into direct contact with the passengers and can thus deliver their heat without detours, which is not only more efficient theoretically but also in practice, according to Ford’s results.

“We all know that if the doors or windows are opened when it is colder outside, the temperature inside a vehicle drops,” says Markus Espig, Systems Engineer, Propulsion Systems Engineering, Ford Research, and Innovation Center Europe.

“This is especially true for delivery vans, as drivers make frequent drop‑offs and the heat generated via aircon is lost more quickly, while heated surfaces stay warm,” he continues. “Reducing energy use not only improves range, but it also cuts costs and helps ensure that the way we travel is more sustainable.”

More than just seats and wheel

Since heating the interior air is very inefficient, especially on short journeys (such as commuting), contact heaters such as heated seats and heated steering wheels are usually the more efficient way to maintain a sufficient feeling of warmth. That’s why these two contact heaters are already widely used in cars, especially electric ones.

Heated armrests, floor mats, or door panels, on the other hand, are not yet common. Only in some luxury models may there be heated armrests. Ford has now proved that expanding the heated surfaces can improve heating efficiency even more. Earlier this year, the automotive supplier ZF made headlines when the company announced a heated seat belt.