V2X-Capable Vehicles: A Potentially Significant Adder to Grid Resiliency

(Rick Sander, CEO, Tuesday March 2, 2021)

As the weather event in Texas last month demonstrated, there are many factors that affect the resilience of the US power grids. One thing that seems true is that like for any event, it is important to factor in unexpected situations (“Murphy’s Law” – whatever can break, will). In the case of the Texas weather-induced electricity crisis, the unexpected situation was that several natural gas power plants were unexpectedly taken offline when their natural gas wells and pipelines froze solid. The situation caused the loss of roughly 40% of Texas’s energy generation capacity, or about 400GWh of power per day (on average, Texans use roughly 1TWh of power per day). But what if there had been another source of power that could have stabilized the grid? Vehicle to anything (V2X), which includes vehicle to grid (V2G), vehicle to building (V2B), vehicle to infrastructure (V2I), and vehicle to home (V2H), could be that source.

In the 2018-2019 school year, Texas had 49,608 school buses, or roughly 10% of total US school buses. The average electric school bus has a capacity of 150kWh, meaning that if all of these buses were electrified they represented an electricity storage capacity of 7.44GWh. US truck fleets had 4.7M vehicles in 2019; applying the 10% number above to these trucks would indicate that Texas has 470,000 trucks. Again, if all of these were electrified and had a similar battery capacity to buses (we will assume 150kWh per vehicle), these trucks could supply an additional 70GWh of energy. And finally, consumer-owned vehicles: Texas had 8.23M registered autos in 2018. Excluding the trucks and buses above would reduce this number to 7.7M vehicles. Assuming 50kWh of power storage per car would mean that these vehicles could supply 385GWh of energy, for a total of 462GWh. While this may be not be a realistic situation (at least for a few decades), there are those who would say that a state losing 40% of its electrical generation capacity is equally unlikely. If nothing else, this exercise does illustrate the potential for V2X to mitigate grid availability and stability issues. Of course, you don’t just need V2X-capable vehicles; you need a V2X capable charging infrastructure as well.

Rhombus has built high-power DC fast charging systems and smart inverters for renewable energy such as “behind the meter” grid energy storage systems for several years. We have applied that expertise to the design of our latest-generation bi-directional EV charging systems (which are designed from the start for the needs of fleet operators) and bi-directional smart inverter systems for microgrids. Rhombus 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. Rhombus also excels in the design and testing of high-power electrical equipment to meet the requirements of UL and other certification organizations. We have built hundreds of 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.