There are three categories of chargers: Level 1, Level 2 (L2), and DC fast chargers (DCFCs). Level 1 chargers are the equivalent of plugging your car into a normal electrical outlet, so most often are not used for commercial fleet charging; fleets typically choose between Level 2s and DCFCs. 

Level 2 chargers don't cost as much as DCFCs, so many fleets choose them as the default option. However, there are some good reasons to choose DCFCs, especially if you need fast charging or operate heavy duty vehicles. Let's first look at all of the differences between the two.

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Differences between Level 2 and DCFCs

Maximum power output

Level 2 chargers typically range between a 7 and 21 kW power rating, and DCFCs can be rated between 40 and 350 kW. With a higher power output, DCFCs can charge your vehicle faster. A DCFC can charge a delivery van in 30 minutes, whereas a Level 2 charger may take overnight.

Cost

DCFCs are much more expensive than Level 2 chargers, by an order of magnitude or more. A DCFC unit can cost from $20,000 to $100,000, whereas Level 2 chargers range from $500 to $5000.

Site power infrastructure requirements

Because DCFCs require ~10-20x or more power than a lower-end Level 2 charger, there is a risk that a site’s electrical infrastructure won’t be able to support more than 1 or 2 DCFCs. For example, if your power panel is rated for 1000A, it can support around 30 Level 2 chargers, but fewer than 8 DCFCs. Working with your utility to upgrade your site’s electrical infrastructure to support DCFCs can take 1-3 years.

Data reporting: state of charge and vehicle ID 

As discussed in Flipturn’s previous blog post, DCFCs provide more data than Level 2 chargers. Level 2 chargers are able to report real-time information about charging status, power usage, and cumulative energy usage across a charging session. However, they do not report which vehicle is charging at the charger; vehicle identity and state of charge information must come for vehicle telematics.

On the other hand, DCFCs report the ID of the vehicle plugged in, as well as the real-time state of charge of the vehicle. With this extra information, a charger management system such as Flipturn can predict when a vehicle will be fully charged, control charging speed based on vehicle identity or schedule, and more. This functionality is only possible on L2 chargers with data sources such as telematics or manual input to associate vehicle identity and state of charge with a charging session.

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What’s right for your fleet?

Because L2 chargers are much cheaper than DC fast chargers to purchase and install, they are often the most practical option. However, not all fleets can charge using L2 chargers: a L2 charger may not charge a vehicle quickly enough, and are impractical for many heavy duty vehicles. 

You may opt for DCFCs if any of the following apply to your fleet.

Incentive and grant programs eligibility

As mentioned above, DCFCs cost an order of magnitude more than Level 2 chargers. However, there are ample incentive programs out there that will subsidize the purchase and installation of DCFCs. In particular, there is a lot of money available in California for constructing DC fast charging sites. Before investing in charging infrastructure, make sure to check whether you might qualify for your charging infrastructure to be subsidized.

Short dwell times for charging

If your vehicles need to charge in 1 hour or so, you’ll need a DCFC. If you have time to charge overnight, L2 can be enough. 

Think of pouring water into a glass: the rate at which you pour water affects the amount of time it will take to fill the glass. EV charging is similar: a higher kW charger will fill a vehicle’s battery faster than a lower kW charger. Because a DCFC can deliver 10-20x as much power as a L2 charger, a DCFC can charge your vehicle up to 10-20x faster than a L2.

Heavy duty vehicles 

Heavy duty vehicle fleets usually need DC fast charging, though bus fleets have short enough routes to charge overnight with L2 chargers. Light and medium duty fleets can usually choose L2 chargers, but may also install 1-2 DCFCs on site for quick opportunity charges.

The glass-of-water metaphor also applies here: the larger the glass, the longer it will take to fill the glass at the same pour rate. EV charging is similar: a class 8 truck has a bigger battery than a delivery van, so will take much longer to charge with the same charger. While a level 2 charger can charge a delivery van overnight, it may take days to charge a class 8 truck, and leaving your vehicle parked at a charger for days is not realistic for most fleets.

Visibility needs

As mentioned above, L2 chargers are unable to directly provide information on vehicle state of charge or identity. As a result, most charging management systems will not be able to provide detailed visibility into level 2 charging sessions, including information about which vehicle is charging at each charger, or the estimated time until charging completion. 

In some cases, Flipturn is able to use vehicle data integrations to map L2 charging sessions to vehicles, and use this mapping to report state of charge. While AI-powered matching can help provide greater visibility into depot operations, this is dependent on good data quality from vehicle telematics. At Flipturn, we’ve found that vehicle data quality can vary widely across different vehicle makes and models. As a result, you may opt for DCFCs if detailed vehicle-first visibility into charging is a top priority.

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Conclusion

Overall, fleets with class 2 or 3 vehicles (passenger cars, delivery vans, etc) often choose to opt for level 2 charging, whereas most heavy duty fleets need to install DC fast chargers. While this makes sense from a budgetary and logistical standpoint, fleets that operate level 2 chargers may then struggle with access to detailed visibility across their L2 charging depots. 

At Flipturn, even with level 2 charging, we are able to provide greater visibility into vehicle readiness, state of charge, and scheduling. If this is interesting to you, feel free to reach out for a demo!

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