When Does Sharing a PCS Across Multiple Dispensers Make Sense?

Joseph Gottlieb, CTO, Tuesday August 10, 2021

Our last blog explored why remote dispensers, where the dispenser functions are separated from the power electronics systems (often called the power control system, or PCS), are popular for medium- and heavy-duty (M/HD) electric vehicle (EV) fleets. Going on the theme from last week’s blog, another question we often hear from customers is “can I connect multiple dispensers to a single PCS?” After all, the PCS is the most expensive part of an EV charging system – if you could connect multiple dispensers to a single PCS, it could significantly reduce the electric vehicle support equipment (EVSE) portion of the total cost of ownership of a M/HD EV fleet. So can you share a PCS across multiple dispensers, and when does it make sense to do so?

The answers are: i) yes, you can share one PCS across multiple dispensers; and ii) , and ii) it really depends on the use case. If you are charging large transit buses with equally large batteries (for instance, a Proterra ZX5 MAX with a 600kWh battery), the bus uses most of that charge on its route during the day, and has a 9-hour charging window, it is unlikely that sharing a PCS across multiple dispensers will make sense – you would need an extremely powerful PCS (think 200-300kW capacity). If on the other hand you are operating a fleet of delivery trucks with 100kWh batteries that use 90% of their energy per day (on average) and the same 9-hour charging window, a 60kW PCS could easily charge 5 vehicles during the charging window. Of course, the ability to share a PCS across multiple dispensers is not free, but with the right use case, a shared PCS could have an overall lower system cost than the typical dedicated PCS per dispenser approach.

If you are looking for made in the USA high-power DC fast charging systems for those EVs, look to Rhombus Energy Solutions. Our market-leading bi-directional EV charging systems (which are designed from the start for the needs of fleet operators) are designed and built in the USA. Rhombus also excels in the design of high-power smart inverters for next-generation renewable energy and energy storage deployments. Our expertise in energy management system (EMS) software is also embedded in our VectorStat EMS controller and software which is embedded in our EV charging systems and smart inverters. We have built over a thousand V2G-capable high-power, high-reliability chargers and bi-directional smart inverters for a variety of different sizes and classes of EVs.

Find out how we can help you by contacting us at news@rhombusenergy.com, or by reading our Vehicle to Grid Solution Brief.