You’ve likely heard scary phrases related to EV charging like “demand charges” or “peak charges.” These are things you want to avoid as it means that you’re plugging in your electric truck when energy demand is high and costs are at a premium. We’re about to give you a crash course in electric truck charging station software capabilities and its impact on ROI. After taking us through the charging station basics, Rich Mohr, global vice president fleet at ChargePoint, dove into charging use cases and how to best leverage charging software to help control energy costs.
“We have customers that are under extremely tight energy constraints when you start talking about demand charges and peak charges,” Mohr noted. “What we do is train the chargers to use different methodologies. Slow and low is always the best option, but you have to allow for opportunity charging in the string. If a customer is maxed out on a site at 200 kW, then they can’t exceed that kW usage, at any time, for more than 15 minutes or it puts them in a demand charge. With our software, we can set the fleet to charge at a maximum threshold of 200 kW at any given time, so that they never exceed that threshold.”
The “string” that Mohr refers to is the lineup of chargers at a site. They’re all connected to each other underground. How much power those strings use and how many strings you have on site are all determined by your installation process. (We covered that with Mohr in another story that you can read here.) How many chargers, how many strings and what’s also attached to those strings, like your building power (potentially), all add into your energy usage and approaching demand charges.
“We have a fleet in California running 16 electric vehicles with a cap of 200 kW across their string, but they’re constantly bringing in electric yard tractors into that operation that are moving trailers around all day,” Mohr explained. “When that yard tractor comes back, that tractor has to charge right away, and it can’t charge low and slow. Our software gives that tractor the maximum amount of charge for 15 to 30 minutes, and then it goes back on route. At the same time, the fleet operator receives communication from the system that the vehicles are ready or that it’s at a specific state of charge or that the opportunity cost was X.
“We don’t exceed that ceiling in high demand areas. It’s important to balance energy usage across your charging solution. You just can’t put in 16 dumb chargers and say, ‘Let it rip.’”
What happens if someone forgets to charge a truck?
There’s plenty of intelligence baked into electric trucks and charging stations, but, like many systems, the weakest point in the process tends to be the human. We all make mistakes and move too fast. So what’s the charging software failsafe if someone forgets to plug in a truck?
“We’ve seen it,” Mohr said. “People would back the truck up to the charging station, they’d jump out and they’re exhausted. They just worked all day, and they forgot to charge the vehicle. Within 15 minutes of them not charging the vehicle, we programmed our software to send messages saying, ‘The vehicle’s onsite, but it’s not plugged in.’
“It’s those types of things that make choosing the right charging software really important,” he continued. “We integrate with the telematics device in the vehicle, so we know when it’s in the yard, and then we know when it’s not on the charger.”
If you’re in the market for charging stations, click here to peruse our extensive list of commercial battery electric charging station OEMs. And if you missed our first meeting with Mohr where he discussed charging infrastructure basics, be sure to click here to catch up.