Study of 3,900 electric cars: How the Tesla Model 3 transformed EV charging habits

The Tesla Model 3 didn’t go on sale until halfway through 2017. But in less than three years, the Model 3 has radically shifted how and when EV drivers charge their cars. That comes through loud and clear when comparing the charging patterns of EVs in 2014 and 2019. FleetCarma, which helps utilities understand and manage EV charging, today published data based on a new study of 3,900 electric vehicles.

The Tesla Model 3 represented nearly half of all EV sales in the US in 2019. That shifted the entire market to long-range EVs — resulting in electric cars charging faster and driving further. The Chevy Bolt also contributed to these changes.

In its new report, “EV Growing Pains,” FleetCarma explains:

The long-range BEV has increased in proportion to new electric vehicle sales from 14% in 2014 to 66% in 2019 in the United States.

Long-range BEVs are very different from older electric vehicles. They are driven more, they consume more energy, they draw power at a higher level and they are less predictable.

The drivers come from FleetCarma’s SmartCharge Rewards programs offered by utilities. In total, the company studied charging, and driving habits from 40 different EV makes and models. It looked at 2.3 million hours of charging and 28.9 million miles of driving data — from vehicles across North America. All the data was collected last year, and then extrapolated the changes in behavior between 2014 and 2019 EV vehicle groups.

Long-range BEVs, like the Model 3, draw electricity at twice the power level.
The charging load nearly doubled from 4.5 kW on average in 2014 to 9.7 kW in 2019. Five years ago, the average charging session added 9 kWh. Now it’s nearly doubled to 18 kilowatt-hours.

Drivers are charging less frequently.
Long-range BEVs do not charge every day. FleetCarma data shows that vehicles spent more time charging per month in 2014 than they did in 2019. To be clear:

• Hours charging per charge increased, but hours charging per vehicle per month decreased.
• In 2019 long-range BEV drivers charged on average 19.18 times per month, compared to 28.67 and 30.73 times per month for short-range BEVs and PHEVs, respectively.

More home charging is happening in the wee hours.
The charging load from these drivers is getting pushed to off-peak hours. With so many EV drivers having long-range vehicles with faster charging rates, it could have a big impact on utilities. That’s because EVs would typically charge as soon as the driver returns from work.

However, EV drivers and utilities have become savvy. Lower time-of-use rates and other incentive programs are working. EVs from the 204 vehicle group (with smaller batteries and slower charging rates) on average actually pulled more max power from about 1 pm to midnight than the long-range 2019 fleet.

The main message of the FleetCarma is for utilities to prepare for a future in which nearly all EVs have long-range batteries and even more powerful home charging options.

The fleet management company advises, “With the popularity of EVs increasing, along with the expansion of models being offered with much higher battery capacities, their destructive potential on utility distribution assets will continue to grow.”