Planning Your Electric Fleet

EV Charger Type Selection

How to Choose an EV Charger: Power Output and Type

When selecting EV charging hardware types for your fleet depot, you need to make some simple decisions and some more complex ones. The EV charging era has progressed past the early adopter stage, which means there is more information available. You can learn from other case studies to get answers to common questions.

  • Which charger type works best for your type of fleet? 
  • Which charger brand is reliable and affordable? 
  • How many chargers do you need for your fleet? 

For instance, if you operate a last-mile site with electric vans charging overnight, you’ll probably want to install chargers with 5-20 kW power output. If you’re in Europe this means AC charger types or if you’re based in the Americas it means DC charging options.

5 to 20 kW chargers allow you to charge the vehicles slowly overnight, potentially charging 2 or 3 vehicles per night. This makes it one of the most convenient EV charging options for fleets with extended idle times.

However, each site is slightly different and has its own challenges. 

  • Do you have ground staff on site who can swap the vehicles? 
  • Do you have enough space to install a 1:1 ratio of charger and vehicles? 
  • Do you need third-party access for contractors or similar?

To help you decide upon the best charging infrastructure to meet your needs, we typically run software simulations. For instance, below you’ll see simulations for a fleet charging overnight a) with slower AC EV chargers, and b) with faster DC chargers to help you find the EV charger option right for your fleet depot..

Ampcontrol EV charger simulation with AC EV charger types
AC charging for 100 vehicles

Ampcontrol EV charging simulation with DC charge points
DC charging for 100 vehicles

If you operate larger vehicles, such as semi-trucks or transit buses, then you must install DC fast chargers (DCFC). While there is a buzz around these different types of EV chargers in the press as they are big and offer a high power output, there are significant downsides such as high installation costs, expensive O&M, and high power demand to establish a grid connection.

When you install DCFCs in your fleet depot charging station, you'll typically find the power output is in the range of 20-700 kW. In some cases you might even install ~1MW chargers. However, the most common range at the moment is 75-360 kW. 

Single vs Multi-Dispenser EV Charger Types

The more important question is how to set up these chargers and maintain power distribution. In general you can differentiate between single dispenser DCFCs (one plug per charger) or multi-dispenser DCFC (>2 plugs per charger). A multi-dispenser setup is where you have one large EV charging power cabinet (including the power modules) which supplies power to multiple chargers. The advantage of this setup is that you need less space in the parking lot with power modules  shared between plugs. This makes it more cost effective overall and an appealing choice among EV charging options for larger fleets. 

However, the downside of multi-dispensers is more complicated power management. Additionally, if one main EV charging power cabinet is faulty, this could mean two or more plugs are out of operation. Single dispenser chargers don’t have this problem, but are typically more costly and need more space. Evaluating the EV charging connector types available in your setup is also crucial to ensure compatibility with your fleet's needs.

Ampcontrol Single dispenser EV charger vs. multi-dispenser and Ev charging power cabinets
DCFC with main cabinet and with single dispenser

How to Choose the Best EV Charger Brand

Selecting your charger brand is at least as important as selecting your EV brand. The decision is more theoretical and can be more complex. Your decision is not only based on purchase price. Instead, you evaluate total cost of ownership of the charger, support options, warranty, grant options, and technical feasibility. Considering different types of EV charging stations is vital to ensure compatibility with your fleet's needs, and potential growth.

The most common challenges we’ve seen amongst our sites include the following.

  • EV charger types offered by the manufacturer don’t align with operational needs.
  • EV charger manufacturer has poor support and responds to tickets slowly
  • Onboard software is unreliable. Updates are slow or cause operational problems.
  • Components break often and need constant maintenance

If you’re planning to operate hundreds of EV chargers, you’re looking to partner with a charger brand for the next ten years, at least. We’ve seen very successful partnerships with European or American companies. We’ve also seen good partnerships with Asian brands that often come at a lower price point and have more experience in the larger Chinese EV market. Exploring EV charging options, including DCFC charging stations, might also help identify brands with proven success in large-scale operations.

The best way to simplify your selection process is to down-select or shortlist 3 or 4 brands, then  test them in a lab or with a simulation software partner like Ampcontrol. You’ll quickly identify which ones work best and highlight potential good partners. You might also want to select two charger brands instead of one. This reduces the chances of vendor lock-in and minimizes your long-term risk.

Outline

Type of EV charger

Number of chargers

Selecting the brand