May 15, 2023

EV charging site installation fundamentals

JuicePedestal charging Honda Clarity PHEVs

Once you get a sense of the benefits of EV charging—whether public or private—for your organization, how do you take the next step? Installing smart chargers requires foresight, especially if you want to use federal, state and utility incentives to keep your capital expenditure low.


Every site and organization has its own set of specific needs, but after working with thousands of organizations to help them get EV supply equipment (EVSE) set up, we’ve developed this set of fundamental installation considerations every organization should consider. 


Always keep different charging levels in mind

As you work through this list, it helps to remember the different “levels” smart chargers come in, their requirements and their capabilities. Level 2 chargers—the most common for commercial installations—strike a balance between charging speed and affordability.  They charge at speeds ranging from 7.7 kW to 50 kW. If an EV uses 25 kWh to drive 100 miles, a Level 2 charger could replenish between 31 and 200 miles of range in an hour. Level 2 smart chargers use 240 voltAC power, which may not require new electrical wiring or upgraded electrical panels, depending on how your site is already laid out.


Level 3 smart chargers (a.k.a. DC fast chargers) offer the quickest charging times, with charging speeds between 50 kW and 350 kW. At the top end, they can charge an EV from empty to 80% full in under 20 minutes, and that time is shrinking every year as charging technology improves.  Because they rely on direct current and require a minimum of 480V, they almost always require infrastructural upgrades. 


1. Assess the feasibility of your site

Conducting a thorough site assessment is a crucial first step in the process of installing EV chargers. This evaluation typically involves working with a qualified electrician or engineer to determine your site’s capacity to handle the additional load of EV chargers. 


Have them estimate the cost of infrastructural upgrades for various EVSE configurations: Level 3 chargers, Level 2 chargers, and a mix of the two. It costs far less to build out infrastructure for all the charging stations you might add in the future than it does to do the work piecemeal. Virtually every additional foot you have to dig up to lay cable increases cost. And if walls have to be taken down or altered, that can exponentially increase cost.


If you’re installing DC fast chargers, you’ll at least need to upgrade your conduit and wiring as well as your grounding and surge protection. You may also need new metering and monitoring equipment, a new load management system and a higher voltage distribution panel. 


In addition to electrical capacity, you'll need to consider the physical layout of your property. Account for available parking spaces, current access points and traffic flow, then ask yourself where chargers would be most convenient. From both cost and convenience perspectives, not all parking spaces are equally well suited for EVSE installation. An inconvenient parking space can deter EV traffic to public chargers, or decrease efficiency for fleet charging. Here are a few examples to consider: 


  1. Some EVs like the Nissan Leaf, have charging ports on their hood, and others like the Ford F-150 Lightning have them on their sides. So an EV space abutting tight walls on two sides creates extra work for the driver when trying to park, especially for larger vehicles. 

  2. If you place an EV charger such that the cable from one charging plug lies across a second parking space when plugged in, you risk having it driven over again and again and shortening its life. 


2. Make sure your site will be safe, appealing and up to code

You need to understand local building codes and regulations related to EV charging infrastructure to ensure compliance and obtain any necessary permits. Many local building codes require minimum numbers of EV charging or “EV ready” spaces (i.e. spaces that could have EVSE connected to them without additional infrastructural upgrades) in parking areas. If you're going through the work of installing EVSE, you should make sure you’re up to code and future-proofed against coming regulations.  


Consider providing proper lighting and surveillance cameras around the charging stations to enhance visibility and security. Remember, drivers will have to stand facing the charging station while they pay. Doing that alone at night can be unnerving enough to avoid entirely if the environment is poorly lit and isolated. Additionally, make sure that the chargers are accessible to all users, including individuals with disabilities.


Ideally charging stations will blend seamlessly with the existing surroundings and, if anything, add to the overall visual appeal of your parking lot. Adding signage, greenery, shade structures create an inviting environment for EV drivers.


3. Estimate charging demand and usage patterns 

With EV adoption growing as quickly as it is, it can be tricky to estimate demand for your site. Especially if you’re installing public chargers, demand in 2023 is bound to be lower than demand in 2026 or 2030. Use the Enel X Way App to locate nearby chargers and this interactive map to see charging station density by county. For a broader picture of trends, the US Department of Energy has this state-by-state breakdown of EV registrations over time. It’s an excellent snapshot, though the data lags by at least a year. 


Together those will give you some sense of what demand to expect. You might also want to conduct surveys or seek published data on the charging needs of your target audience. 


Demand is half the equation; the other half is when the EVSE will be used. While the market or your business needs dictate much of this, how and where you place your chargers have a role to play. 


If your chargers are for public use, consider the usage patterns of your customers. How long do they typically park their vehicles on your property, and how long do you want them to be there (i.e. target dwell time)? Here are a few examples:


  1. A convenience store owner is looking to add EVs to drive charging revenue and in-store purchases. Most customers spend three to five minutes at the store while pumping gas. They want to increase dwell time to 10 minutes, but worry that requiring customers to stay longer would discourage them from stopping. 350 kW DC fast chargers like the JuicePump 350 kW are the right option here. 

  2. A grocery store operations manager wants to use free public charging as a competitive edge over other grocery stores in the neighborhood. With such low margins, traffic volume is critical to their business. As is dwell time: the longer customers spend in the store, the more they spend. Level 2 smart chargers like the JuiceBox 32, which could replenish a day’s worth of commuting to and from work in an hour, are perfect in this instance.

  3. A property manager for an urban public parking garage that primarily caters to the office buildings, shops and restaurants around it wants to add paid public chargers to increase revenue, meeting customers where they are rather than trying to change behavior. Customers average a three hour dwell time, but times range significantly, from 30 minutes to 12 hours. A combination of DC fast chargers and Level 2 chargers will deliver the most flexibility to customers and allow them to keep charging payments flowing in. 


4. Bring it all together

When you’ve got a sense of what your site can handle and what will make it appeal to your target users, you’re ready to estimate the total number of charging stations you should install. Of course this number will be mediated by cost and incentive availability, many of which have minimum charging station requirements to qualify for funding.


If your EVSE is just meant to serve your fleet, here’s a straightforward way to assess the number of chargers to purchase, with examples to follow. These examples assume the site can handle the electrical load of as many chargers as it needs and has sufficient space.


  1. Assess the maximum number of vehicles that would need to charge at the same time

  2. Calculate the total number of miles those vehicles drive between charges 

  3. Divide #2 by #1 to get the average miles of required recharge per EV

  4. Determine how long your maximum number of vehicles will have to recharge (i.e. how long they’re parked)

  5. Divide #3 by the number of hours in #4 to get the total hourly demand

  6. Find the average number of kWh required to add one mile of charge to one of your EV fleet vehicles (this information is readily available for any EV on the market, generally expressed as kWh per 100 miles)

  7. Multiply the total hourly demand by #6 to get your kW requirement per charging port


Here are two simple examples to help you visualize.

Example 1: Last Mile Delivery Fleet


  1. 50 vehicles recharge at once

  2. Those 50 vehicles drive a total of 20,000 miles per day

  3. 20,000/50 = average miles of required recharge per EV = 400 miles

  4. Those 50 vehicles recharge in the 10 hours between 8pm and 6am

  5. 400 miles/10 hours = total hourly demand = 40 miles of recharge per hour

  6. Fleet vehicles require 0.25 kWh to replenish one mile of range on average

  7. 40 * 0.25 kWh = fleet hourly consumption = 10 kW per port


If the operator in this example wants to avoid having anyone onsite dealing with moving vehicles overnight, they’ll need one charging port per fleet vehicle: 50 total ports. The lowest power Level 2 smart charger will deliver plenty of charge, but without incentives those will still cost an average $4,700 each for hardware and installation. So it might be more economical to have someone move charging plugs once in the middle of that 10 hour window and install half as many chargers. Level 2 smart chargers deliver enough power that they could buy the same model in either instance. 


Example 2: Foodservice Fleet


  1. 10 vehicles recharge at once

  2. Those fleet vehicles drive a total of 1,000 miles per day

  3. 1000/10 = average miles of required recharge per EV = 100 miles

  4. Those 10 vehicles recharge in 15 minute windows at all times of day

  5. 100 miles/0.25 hours = total hourly demand = 400 miles of recharge per hour

  6. Fleet vehicles require 0.35 kWh to replenish one mile of range on average

  7. 400 miles of recharge per hour * 0.35 kWh = fleet hourly consumption = 140 kW per port


In this example, the operator will need 10 DC fast charging ports accessible at all times, which could be accomplished with five JuicePump 350 kW chargers. 


If your primary purpose for the chargers is public use, estimating the right number of charging stations involves more market research and informed assumptions. Combine what you gathered from the maps and EV registration data linked earlier in this post with budget considerations informed by your site assessment and any available incentives you qualify for. 


Build the future of EV charging Infrastructure

Whether you’re installing public or private chargers, it should be clear that these installation fundamentals can get complex and quite subjective. Working with an experienced charge point operator and consultant like Enel X Way can expedite the whole process and deliver peace-of-mind that’s hard to find if you go it alone. 

Take the next step towards EVSE at your site

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