Geek Out on the Tech to Launch Smart Electric Vehicle Charging

Do convenience store managers need to be seasoned energy experts to adapt to the rapidly growing electric vehicle (EV) trend? Not necessarily, but they can make a more informed decision by understanding the technical side of the equation.
Here are some variables to keep an eye on, even if your day-to-day work revolves more around accounting and business strategy than electrical engineering or network management.
Lawmakers last year approved $7.5 billion to build a network of 500,000 public electric vehicle chargers, but they want the funds to go only to high-capacity DC chargers.
Ignore adjectives like “super-fast” or “lightning-fast” in DC charger ads. While federal funding is in progress, look for Tier 3 equipment that meets the specifications outlined in the National Electric Vehicle Infrastructure (NEVI) formula program. At least for passenger car chargers, this means between 150 and 350 kW per station.
In the future, lower power DC chargers are likely to be used in retail outlets or restaurants where the average customer spend time exceeds 25 minutes. Fast growing convenience stores require equipment that meets NEVI formulation standards.
Additional requirements related to the installation, maintenance and operation of the charger are also part of the overall picture. FMCG retailers can consult with lawyers and electrical engineers to find the best way to win EV charging subsidies. Engineers can also discuss technical details that greatly affect charging speed, such as whether the device is a standalone or split architecture.
The US government wants electric vehicles to make up half of all new cars sold by 2030, but reaching that goal could require 20 times the country’s current estimated 160,000 public electric vehicle chargers, or by some estimates, about 3.2 million in total.
Where to put all these chargers? First, the government wants to see at least four Level 3 chargers every 50 miles or so along major transportation corridors of the Interstate Highway System. The first round of funding for electric vehicle chargers focused on this goal. Secondary roads will appear later.
C networks can use the federal program to decide where to open or renovate stores with an electric vehicle charging program. However, an important factor is the adequacy of the capacity of the local network.
Using a standard electrical outlet in a home garage, a Level 1 charger can charge an electric vehicle in 20 to 30 hours. Level 2 uses a stronger connection and can charge an electric car in 4 to 10 hours. Level 3 can charge a passenger car in 20 or 30 minutes, but faster charging requires more power. (By the way, if a new batch of tech startups get their way, Tier 3 could go even faster; there are already claims of 10 minutes on a single charge using a flywheel-based system.)
For every Level 3 charger in a convenience store, power requirements can increase rapidly. This is especially true if you are loading a long haul truck. Serviced by fast chargers of 600 kW and above, they have battery capacities ranging from 500 kilowatt hours (kWh) to 1 megawatt hour (MWh). In comparison, it takes the average American household a whole month to consume about 890 kWh of electricity.
All of this means electric car-focused convenience stores will have a big impact on the local chain. Fortunately, there are ways to reduce your consumption of these sites. Fast chargers can be designed to switch to power-sharing mode when the charge levels of multiple ports increase. Let’s say you have a charging station with a maximum power of 350 kW, when a second or third car connects to other charging stations in this parking lot, the load on all charging stations is reduced.
The goal is to distribute and balance the power consumption. But according to federal standards, level 3 must always provide at least 150 kW of charging power, even when splitting the power. So when 10 charging stations simultaneously charge an electric car, the total power is still 1,500 kW – a huge electrical load for a single location, but less demanding on the grid than all charging stations running at full 350 kW.
As mobile stores implement fast charging, they will need to work with municipalities, utilities, electrical engineers and other experts to determine what is possible within growing network constraints. Installing two level 3 chargers may work on some sites, but not eight or 10.
Providing technical expertise can help retailers select EV charging equipment manufacturers, develop site plans, and submit utility bids.
Unfortunately, it can be difficult to predetermine network capacity because most utilities don’t report it publicly when a particular substation is nearly overloaded. After c-store is applied, the utility will conduct a special study of the relationships, and then provide the results.
Once approved, retailers may need to add a new 480 volt 3-phase mains to support Tier 3 chargers. It may be cost effective for new stores to have a combo service where the power supply serves 3 floors and then taps to service the building rather than two separate services.
Finally, retailers should plan scenarios for wider adoption of electric vehicles. If a company believes that two chargers planned for a popular site could grow to 10 one day, it might be more cost-effective to lay additional plumbing now than clean up the pavement later.
Over the decades, convenience store decision makers have gained significant experience in the economics, logistics and technology of the gasoline business. Parallel tracks today can be a great way to beat the competition in the race for electric vehicles.
Scott West is a senior mechanical engineer, energy efficiency specialist, and lead designer at HFA in Fort Worth, Texas, where he works with several retailers on EV charging projects. He can be contacted at [email protected].
Editor’s Note: This column only represents the author’s point of view, not the convenience store news point of view.