We recently put Renault ZOE through its paces in Lapland. All summer long we have shown you each step in the genesis of the new model, from design to crash tests. And now we are going to look at a decisive phase in the conception of our electric city car: cold weather tests.
Vehicle powertrains and mechanical components are subjected to tough conditions in winter. So we have to make sure that the cars we put on the road can resist extreme temperatures. Other components apart from the engine are closely monitored. The gearbox, for example, must not be restricted or slowed down by extreme cold.
We check a broad range of equipment, including the heating, and pay close attention to the quality of defogging and defrosting systems and the correct operation of shock absorbers and the ABS in snow. We also ensure that no snow gets under the hood or builds up on the brakes, which could lead to problems. The only way to properly check these points is through cold weather test drives. Which is why they are so important.
In short, the aim of cold weather tests is to detect any operating problems and solve them. By simulating winter conditions, the tests allow us to validate technological choices that guarantee consistent vehicle behavior and comfort in the most extreme conditions.
As you probably know, an electric vehicle doesn’t react the same way to cold as an internal-combustion vehicle. Renault ZOE doesn’t use oil or gas, so our engineers don’t have to monitor these items. But other Renault ZOE components required particular attention during cold weather testing.
First of all, we had to examine how cold weather conditions affect the battery, notably in terms of:
We also had to check the charging system:
Our first conclusions on Renault ZOE's results: At -25°C, Renault ZOE is fully functional and drops in performance are almost unnoticeable. The battery performs very well in cold conditions from this point of view.
More noticeable in cold conditions is reduced range, but Renault ZOE remains one of the best mass-produced electric vehicles in this respect, thanks in particular to its reversible heat pump, which reduces heating consumption in cold weather and generates approximately 2kW of cooling or 3kW of heat with just 1kW of electricity.
Renault ZOE performs strongly, especially compared with internal-combustion cars, on the following points:
Our engineers were pleasantly surprised by Renault ZOE – by the fast-action heat pump, by the strong performance of the battery on power in cold conditions and its ability to start the motor at very low temperatures, and by the car’s road holding, especially grip on slippery surfaces. The battery’s central and low position is a big advantage here.
Many thanks to Fabrice Izzillo, features engineer for Renault’s electric vehicle range, for all this information.