EV Fleets Need Smart Charging, NOT Fast Charging

Why it matters:

Because focusing on fast charging will cost you millions, delay your electrification – and it won’t solve the problem of electrification at scale.

 You do NOT need the fastest chargers.

The Big Picture

Yes, we really want EVs to be just like ICE vehicles – when the gas runs out, you stop for 5 minutes, take a bathroom break, and drive on. But they aren’t, and won’t be anytime soon (more on that below). For the next decade or more, every stop is going to take 30 minutes, 40 minutes, maybe hours. So the question is not “what can I buy to make the stops the fastest”, but rather “how can I charge the vehicles when they would have been stopped anyway”.

It’s not “how can I charge the fastest”, it’s “how can I charge when the vehicles are parked anyway”

For consumers lucky enough to have their own garage – this means charging their car when they’re sleeping. Plain and simple. But if you have to charge a fleet of vehicles, you need to charge a lot of vehicles at the same time. Well, guess what? Your utility limits your power and won’t let you run many fast chargers concurrently – even if you wanted to (and you shouldn’t). And if you only have a few of those – it means you need drivers moving vehicles around all night.

 In 99.9% of cases you can’t install many fast chargers even if you wanted to.

So the right solution is Smart Charging, where you have many vehicles connected to many chargers, and what moves around is the electricity – NOT the vehicles. What you want is a system that can split the power between your vehicles in an intelligent way – based on what they need, when they are leaving and where they are going. Such a system can manage the power draw, keeping it within limits, thus making it cheaper to install and operate your facility. It also manages charging speed so vehicle batteries stay healthy, and minimizes the amount of moving vehicles around needed – so that you waste less driver hours.

Smart Charging charges many EVs concurrently, optimizing power to fit the vehicles’ needs and the energy available.

Wait A Minute, So What’s The Problem With Fast Charging?

First, what we call “fast” charging is actually slow compared to refueling. Batteries are NOT fuel tanks. Physics dictates that pushing electrons into them too fast affects the materials, creating heat and deformation. Charge fast and you degrade your battery quickly. Charge too fast and it will catch fire. The on-board software in the vehicle will limit charging speed to what the battery can take – regardless of the fast charger output.

Battery technology does NOT change very fast. The batteries that will be installed in vehicles sold over the next 5-10 years will, at best, take 20-30 minutes to “fast” charge and if you do that too often they will degrade very quickly. And even 30 minutes is too long to just stop at an EV charging station every 300 miles. Think of the driver time overhead. Consider how many vehicles need to fit into a “station” at once.

So – the right thing is to charge your vehicles when and where they are already stopped.

You need dedicated chargers – in your parking lot.

Once you realize that it’s about charging the vehicles where and when they stand already – what you want is as many chargers as possible. So the driver dropping off just connects and leaves. For most fleets that means overnight charging. This allows you to charge slowly. How slow depends on how much your vehicles drive per day. But for most fleets Level 2 AC charging is fine, 99% of the time.

Unless your vehicles go hundreds of miles per day – Level 2 is fine.

So why does it have to be smart? This is where power constraints come in. If you try to put in a lot of chargers (that means a lot of “slow” chargers or a few “fast” chargers) you will quickly find out that your utility will take years to get you the service upgrade you need. Smart charging means that there is a system that manages the power such that you can stay within the boundaries of what you have – through a combination of scheduling / staggering when each vehicle is charged, and the use of additional resources like energy storage (batteries), solar or other power generation.

My vendor says the chargers are smart. Is that enough?

Every AC charger that can be controlled remotely (e.g. via cellular, WiFi etc.) is marketed as “smart”. But just because a charger can be controlled, it doesn’t make it smart. The intelligence resides in the software system that tells these chargers what to do, not in the chargers themselves. A smart charging system needs to know everything – which are your vehicles, how much energy they need (i.e. how far do they need to go tomorrow?), what are your sources of energy, what are the power limits and the costs per kWh, which chargers you have and what is connected to them.

Only a system that has all this information can make smart decisions regarding which vehicle to charge when and how much – and how to manage the energy and power at your disposal. We sometimes describe this as “air traffic control for charging” – you need to know who is where, what they need, and how to get it to them and direct the vehicles and the energy correctly.

Smart charging manages your EVs, your energy and your chargers in one place. We call it “Air Traffic Control for Depots”

So what are fast chargers good for?

In a site that is designed thoughtfully, a couple of fast DC chargers can handle the exceptions – those vehicles that did not have enough time to charge, because they got there late / had to leave early / weren’t connected in time – and by fast charging you can make sure they are ready for their missions the next day. Remember – fast charger costs 10 to 100 times more than a level 2 charger. Unless you’re powering class 8 trucks or large transit buses – you probably don’t need many of these.

Why is this so complicated?

Change is hard, and folks (and that include fleet managers) want things to be as they are.

But EVs are different from ICE, and if we are serious about decarbonizing transportation, we need to learn to operate them. The good news is that smart charging software systems coupled with well designed charging infrastructure operate intelligently automatically – taking the complexity out of the system. When we build it right, it’s as simple as park, connect, leave. The software will take care of the rest.

Shameless plug:

Port OS is a smart charging system that is built to do all of this and more.

Contact us if you want a real solution to your fleet electrification headache.