Sticker Shock

The Cost of Charging Your EV Fleet Doesn’t Have to be Shocking

I can predict the future.

I can’t predict what’s going to happen to the price of Microsoft stock tomorrow, who is going to win the World Series, or how long Travis Kelce and Taylor Swift will date before they break up and she writes another #1 hit.

Lower EV electricity costs with automatic demand managementBut when it comes to charging EV fleets, I can make a prediction that is guaranteed to come true: when you open the first utility bill that comes after you get your EV fleet up and running, I know what’s going to happen. Your jaw is going to drop and your blood pressure is going to rise. Almost as much as your electric bill has jumped…almost, but not quite.

Fleet charging sticker shock is common. Fleet Managers and facilities managers are often unprepared for the spike in the electricity cost once EV fleet charging comes online. And the shock extends to the operational budget, which usually has not been adjusted for the upcoming rise in utility bills.

Fleet charging sticker shock is driven by several factors. First and foremost is the length of your charging window (also known as Dwell Time). How long do you have to recharge your fleet vehicles before they have to head out again? The shorter your Dwell Time, the faster you have to charge your vehicles and the greater the impact of charging on your utility bill. Second, what type of chargers are installed? Are they DC fast chargers or are they slow chargers? It matters, and I’ll explain why in a moment. Third, and maybe most important of all, what sort of charge management software (CMS) are you using?

The other key factor is Peak Demand. Put simply, Peak Demand is utility speak for measuring how fast you use energy at any given time during a billing cycle. Nearly every utility charges more for delivering energy quickly. Under their billing formulas (which often require advanced degrees in Sanskrit and fractal geometry to understand how they work), utilities increase the cost of energy ($/kWh) depending on Peak Demand. Higher Peak Demand costs you more per kWh than slower consumption.

Why? Speed costs money. Fast charging needs a fast flow of energy. Fast transmission of energy requires bigger and more expensive transformers, wires, and substations.

Now here’s the kicker: utilities set your rate for the billing cycle based on your Peak Demand. That rate applies to all the electricity you consume during that cycle. The higher your power consumption peak, the higher your rate for that billing cycle for all electricity consumed at your facility – even for the electricity used for non-charging activities.

Charging a fleet adds to power consumption. Charging a fleet all at once, in the shortest time possible, puts your Peak Demand on steroids and your utility bill through the roof.

But spikes in Peak Demand and soaring utility bills are not inevitable when a fleet comes online.

Which brings us back to the key factors you can control. The longer your charging window is, the more flexibility you have to manage power consumption and control peak demand. An example: you have six vehicles to charge. They come in at 6 PM and have to be ready to go at 7 AM. You have 13 hours to charge each vehicle. If a vehicle only takes four hours to charge, you don’t have to charge all your vehicles as soon as they come in. You can spread out the charging and keep your power consumption lower than if you have a shorter charging window and have to charge all your vehicles at the same time.

And that brings us to the type of charger you install. DC fast chargers can operate at up to 350kWh. With fast chargers you may be able to fully charge a fleet vehicle in 2 hours or less. But that doesn’t mean you have to. Charging at max speed boosts power consumption and puts upward pressure on Peak Demand. Charging at a lower kWh rate reduces power consumption at any one time, holding down Peak Demand and reducing the rate you will pay for power.

But none of that is possible without a good CMS in place. A good CMS system should work with any type of charger, recognize the number of vehicles plugged in at any time, and determine (based on inputs from the fleet management) when the vehicle needs to be fully charged and ready to go. With that information, your CMS can control the timing and rate of charging of each connected vehicle with the express goal of reducing Peak Demand, lowering the rate you pay for power, and delivering fully charged vehicles when they are needed.

It sounds simple, but for OCPP-based charging facilities, that level of coordination has not been achievable. Why? Because the CMS systems available treated each OCPP charger as its own discrete universe. If a facility has four chargers using the OCPP protocol, the existing CMS platforms available see four distinct systems and cannot accurately coordinate charging activity across all four.

But that has changed. EVautoLC is the first true OCPP-based local controller. It treats multiple OCPP-based chargers not as independent systems, but as a single system. EVautoLC’s patented algorithms integrate each charger into a single system to manage charging speed across all chargers to hold down power consumption, lower total fleet Peak Demand, reduce the rate you are charged by the utility, and make fleet charging sticker shock a thing of the past.

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