US-based Greenlane builds charging stations for medium and heavy-duty electric trucks. The company's charging site in the Southern California town of Colton is the first of four planned locations along a 280-mile charging corridor between Los Angeles and Las Vegas.
The Colton site offers more than 40 high-speed chargers with a maximum output of 400 kW. When fully developed, it will offer 60 chargers – enough to charge 200 trucks per day.
A charging station of this size uses an enormous amount of electricity. Electric vehicle haters like to compare the power consumption to that of a medium-sized sports stadium. That's fine, but sports stadiums won't bring down the grid, nor will commercial electric vehicle charging stations – as long as appropriate load management systems are in place.
Throw off this burden
Greenlane worked closely with electronics giant ABB on a supervisory control and data acquisition (SCADA) system. This is part of an energy management system that ensures grid stability and enables remote control and monitoring.
The Colton site utilizes two load management solutions: a cloud-based Charger Management System (CMS), which balances electric vehicle charging loads; and an energy management system (EMS) that controls all site loads and power sources, including future installed solar and battery storage systems.
The SCADA system also enables remote operation – it controls and monitors a range of low voltage (LV) circuit breakers and medium voltage (MV) switches. “ABB’s system is unique in its ability to safely open and close all LV and MV circuit breakers remotely,” says Raj Jhaveri, CTO of Greenlane. “This is not typical for electric vehicle charging stations today.”
At the Colton site, Greenlane must carefully manage the energy it receives from the grid. If power consumption exceeds power limits set by the local utility, the site may be disconnected from the grid. Reconnection can take 24 hours or more, and time is money. Therefore, it is important that Colton's own protective circuits kick in first.
The site has multiple levels of load control, including the ABB Ability SCADA platform, which acts as a backup to the CMS. If the CMS cannot maintain charging, the SCADA system initiates a prioritized load shedding scheme when the site reaches 95% of its budget.
Initially, 180 kW electric vehicle chargers will be disconnected one at a time – these stations support long-dwell use cases and charging can be resumed at a later date without affecting the ability to fully charge these trucks in time for departure.
If load shedding does not solve the overload problem, the 400 kW stations will be shut down next. At 97.5% capacity, the SCADA system targets the medium voltage switchgear and shuts off power to the entire site to prevent the utility's controls from causing a complete blackout.
Preparing for the MCS future
Even the abundance of electricity provided by sites like Colton won't be enough to handle the one million electric trucks that Greenlane estimates will hit U.S. roads by 2030. Current technology will limit the ability to convert some existing long-haul routes to electric trucks. This is where Megawatt Charging comes into play – a technology that comes close to commercial reality.
Megawatt charging stations can deliver up to 1.5 MW of power, enough to achieve a range of up to 300 miles within 30 minutes. That's in line with the required rest period for truck drivers in the U.S., allowing electric vehicle drivers to maintain the same schedule as those driving older diesel trucks.
The Colton is designed to be upgradeable to megawatt charging capability when it becomes available.
“Megawatt charging is really the Holy Grail of what we want to achieve,” said Patrick Macdonald-King, CEO of Greenlane Infrastructure. “Faster loading times mean trucks spend more time moving freight and generating revenue, reducing cost per mile and total cost of ownership.”
Source: FIG