Across the nation, fleet operators are transitioning to electric vehicles (EVs). A report from Smart Energy Decisions projects there will be over four million EVs in U.S. commercial and government fleets by 2030. The Biden Administration's 2021 mandate that 100% of the government’s 650,000 civilian and military agency fleet acquisitions be zero-emission vehicles by 2035 is driving much of this conversion, with state and local governments adopting similar targets. However, it's not just the government that is making this change. Large corporations like Amazon, FedEx, UPS, and Walmart are adopting fleet EVs for passenger, shipping, and last-mile delivery vehicles.
Clearly, the adoption of EVs for commercial fleets is rapidly growing. However, as with slower-than-expected individual sales, one of the most significant limiting factors is the lack of charging infrastructure solutions. To support the increasing EV charging needs for commercial and individual automobiles, the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) estimates that 28 million EV chargers will be needed by 2030 to support 33 million EVs. But more EV chargers mean more energy consumption. A lot more energy consumption. By 2035, the share of electricity from non-residential chargers in the U.S. will reach almost 45%, compared to less than 35% in 2023 (IEA). That means supporting the fleet EV transition requires us to massively expand our energy capacity and infrastructure.
Unfortunately, building a fleet charging infrastructure is not as simple as picking out the most suitable EVs and installing chargers. It’s a complex process that must account for factors such as available space at the depot, electrical capacity of the property, and power and maintenance requirements. This makes building a traditional AC charging network costly and time-consuming, taking several years to get through engineering planning, utilities engineering and approvals, and permitting and installation. For example, suppose a utility transformer cannot support increased electricity demand from the depot. In that case, it will need to be upgraded through a process ranging from several months to years, depending on the timeframe for performing grid assessments, forecasting future demand, securing the right equipment, and scheduling crews.
Developing a comprehensive strategy is essential to building an EV fleet infrastructure, but this is entirely new territory for many fleet managers. Without a pre-existing roadmap, the process can become so overwhelming that they don’t know where to start.
Many fleets use traditional AC Level 2 chargers, but these chargers are grid-connected, which requires substantial engineering planning, long permitting wait times, and high costs. AC charging relies on the vehicle’s onboard AC/DC converter to charge its DC battery, which wastes 10-20% of the energy through conversion losses and is often limited to low (<9.6 kW) charge rates.
A DC microgrid is inherently compatible with new green technologies like solar panels, energy storage batteries and EVs, making it far easier to deploy and less expensive than the AC-based infrastructure. In the most common configuration, the DC microgrid directly harnesses PV solar generation as DC power, saving more than 10% of the energy wasted from AC-to-DC conversion losses.
Since most fleet vehicles operate during the day and return to the depot in the evening, charging them directly from PV solar generation is impractical at night. The addition of battery storage systems to the DC microgrid enables excess solar power to be stored and later used for more efficient long-dwell-time (more than eight hours) charging overnight, when EVs do not require expensive, ultrafast charging.
Enteligent’s 25 kW LDF DC-powered electric vehicle supply equipment (EVSE) chargers avoid the energy conversion losses and equipment costs associated with converting solar energy from DC to AC and back again. Enteligent’s approach reduces overall expenses, making clean energy more effective and affordable and expediting its widespread adoption. The fleet charging solution utilizes a commercial scale inverter to efficiently convert grid-level AC electricity to a DC microgrid for the site, including native DC PV solar generation and battery energy storage. The chargers' bidirectionality allows EVs to provide power back to the facility during power outages, ensuring ongoing operations.
The successful transition of fleets from internal combustion engine (ICE) vehicles to EVs requires not only the adoption of EVs but also the development of an efficient, cost-effective charging infrastructure. DC microgrids, such as those supported by Enteligent’s DC-powered bidirectional charger, offer a scalable solution that allows fleet operators to make a fast, efficient conversion.
