Electric vehicle (EV) drivers are usually aware of their remaining range before they need to recharge. In fact, EV drivers are so attuned to their cars that AAA suspended its trial curbside charging assistance service after five years due to lack of demand. Additionally, many EV drivers plan their route based on the location of a convenient public charging station where they can fully charge their car’s battery while doing a variety of other things.
But what if you just need a few extra miles of range to reach your destination? Or maybe you have a few minutes of downtime and are wondering if it’s worth “charging” your car’s battery at a public charger. If you find yourself in this situation, here’s what you can expect from a short-term public charging session.
If you only need a few kilometers
If you drive home and find that your electric vehicle battery is low (similar to being surprised by the low fuel warning light in a gas-powered vehicle), you may need to visit a public charger to make sure you charge it make home
There are two main categories of Public Charging: Level 2 and DC Fast Charging. The slower Tier 2 chargers operate between around 3 and 20 kilowatts (kW), with a higher number offering a faster charge time. Irrespective of this, the on-board charger in your car, also expressed in kW values, affects your charging time.
Given all the variables, it’s difficult to know exactly how long it will take to add, say, 25 miles to the battery. The Department of Transportation estimates that an electric vehicle adds 10 to 20 miles for every hour it plugs into a Level 2 charger. Older EVs and those with slower onboard chargers get closer to 10 miles an hour at a slow station, but perform better at a faster station. The Mazda MX-30, for example, adds about 10 mph when plugged into a 3.6kW station, but 22 miles on a 7kW station.
Not all EVs can take advantage of the higher charging speeds available at some stations. These EVs still accept the charge, just at a slower rate. The MX-30, for example, will cover the same 22 miles in an hour even when hooked up to a 22kW Tier 2 gas station. On the other hand, the high-tech Porsche Taycan works like the MX-30 on slower chargers (11 mph on 3.6 kW, 20 mph on 7 kW) but outperforms the Mazda on a 22 kW Level 2 -Charger by multiples adding 32 miles in an hour. Many charging network operators offer kW ratings in their apps, making it easier to decide where to go when you’re short on time.
As the name suggests, DC fast chargers offer shorter waiting times. The slowest DC fast charger operates at 50kW, while the fastest stations operate at 350kW today, with higher rates planned. The good news is that any DC fast charger will power any compatible EV in just minutes with a range of 10-20 miles, regardless of the station’s kW rating.
If you only have a few minutes
For example, if you have to spend 15 minutes at a public charging station, a Level 2 plug will not be of much help. Level 2 chargers add 10 to 20 miles in an hour, so a 15 minute session will likely add three to five miles. Sometimes that’s enough. Other times, you should look for a DC fast charger.
DC fast chargers can quickly charge an EV battery to 80 percent of its total capacity in about 30 minutes. The more powerful the charging station and the more powerful your electric vehicle’s onboard charger, the less time this will take. However, if you can only sit at a DC fast charger for a few minutes, the station’s kW output can make a difference if your EV can accept the higher tariffs.
The MX-30, for example, offers DC fast charging, increasing range by about 60 miles in 30 minutes at a 50kW station. Due to its limited charging options, it also offers the same additional range at a 150 kW station. The Taycan, on the other hand, can be charged at a higher power, adding about 70 miles in 30 minutes at a 50kW station, but adding over 200 miles at a 150kW station in the same half hour.
summary
Most EV drivers in the United States, especially those who can charge their vehicle at home, should have more than enough range for their daily commutes. But if you haven’t charged your car’s battery all week, or happened to have driven more than expected, you can add a few miles to the range, just like a petrol car. Depending on your region’s charging infrastructure and the electric vehicle you drive, this can take anywhere from a few minutes to one to two hours.
Check out our buyers guide section if you want to learn more about electric vehicles.
