Electric cars and vans are over a third more efficient during warmer months, new data from Mina indicates.

Late spring, summer and early autumn are the best months for EV batteries

Figures recorded by the EV charging payment specialist from May 2022 to April 2023 show that late spring, summer and early autumn are the best months for EV batteries.

The data, which spans more than 350,000 actual charging events, using over eight million kWh of electricity in the process, reveals that during winter, drivers needed an extra plug-in a week compared to September and October to account for reduced battery efficiency and other potential drains on energy such as heating the cabin.

“Our data, recorded by thousands of electric vehicles, proves for the first time what many anecdotal reports had suggested: EVs operate far better in warm weather,” Ashley Tate, Mina CEO said.

But the data also reveals that hot weather can hit efficiency too; the heatwave in late July and August 2022 saw a spike in battery consumption as drivers turned up the air con to full blast. Following the hotter weather, consumption went back to normal for a couple of months, before being hit by the arrival of colder conditions.

Tate said the data was transformational for businesses trying to build a picture of how EVs, and their drivers, operate in all conditions.

“One of the big questions asked about EVs is: how hard are they hit by winter? Well, now we know for sure. There are many factors involved of course, including temperature, routing, vehicle technology and driving style, but for the first time our data is able to show just what the effect is across thousands of vehicles,” he elaborated.

“By looking at consumption for each week, and applying an average domestic tariff for the period of 30p per kWh, we could then show the cost of this for a typical driver. But of course, the cost could be far higher or lower depending on individual circumstances.

“By providing this insight, businesses can plan strategies and budgets with more detail than they have ever had before.”

Mina has stressed the need to put the data into context in line with the overall lower running costs for EVs compared to petrol or diesel vehicles – Tate said the extra winter consumption was only equivalent to two extra tanks of petrol or diesel, and warned that ICE vehicle efficiency can also be hit during winter months as well.

He also emphasised that any driver/fleet wanting to cut charge costs should ensure they’re using the lowest-cost chargers for their needs, including making the most of home charging on cheap tariffs if possible.

“If a driver has an EV-specific tariff and charges exclusively at home at off-peak, the cost could be a third of that quoted, at only around £2.50 a week more. Conversely, if they only charge in public, our data shows it could at least double.”

“Because we track hundreds of thousands of home and public charges and their cost, our data shows the cheapest tariffs are only around 10p per kWh at home and 30p per kWh in public,” added Tate.

“So, if a driver wants to reduce costs, whatever the season, they need to ensure they are on the lowest possible home tariff, and search out the best-value public chargers. It’s all about having the right infrastructure in place that allows drivers to understand and then minimise their costs at all times of the year.”

The analysis is part of Mina’s latest EV Report, which also includes insights on how often, and when, drivers plug in at home, and the effect on the grid. The report can be downloaded for free here.