Vehicle-to-grid Offers Great Storage Potential – GWC Mag

Electric vehicles with their large batteries are currently underutilized as most sit idle most of the time with significant spare capacity to charge or discharge. The technical potential is enormous and growing as more EVs enter the market. Yet using the spare capacity of the batteries to assist the grid when it has too much or too little has been barely explored to date.

That is about to change with the introduction of a new vehicle-to-grid (V2G) standard that could make it much easier for EVs to share both data and power while offering a potentially significant revenue source for the car drivers who are willing and able to charge and discharge at opportune times.

 

The new standard, SAE J3068, recently adopted by SAE International, promises to open the door for EVs to play an active and productive role as portable storage systems. Once implemented to scale, the new standard could turn every EV into a roaming grid battery – and source of revenue.

University of Delaware Professor Willett Kempton, a pioneer of vehicle-to-grid technology points out that enabling EVs to move from serving as a backup battery to being a grid-connected resource is complicated but worth the effort. A key feature of the new standard is its ability to recognize each EV using a unique digital identifier that both the utility and/or the grid operator can use to verify whether they are authorized to supply power to, or store power from the grid, according to Canary Media.

The same certification system can enable the utility to communicate with EVs to stop discharging power if local grid circuits are overloaded or to request that it supply power to mitigate grid disruptions. Moreover, the new standard will make it possible for the utilities or the grid operator to pay EV owners for volunteering their battery capacity for either taking excess energy from the network or feeding it back at a later time.

According to Canary Media a 2021 study by Prof. Brian Tarroja of University of California, Irvine and Prof. Eric Hittinger of Rochester Institute of Technology found that the combined value of the energy-storage capacity of V2G-enabled EVs is roughly double that for smart charging – that is bi-directional charging is twice as good as using the EV batteries for storage only. Not surprising given the challenges of excess/deficit solar as described in the preceding article.

In the Canary Media article Kempton emphasizes the importance of getting utilities, the grid operator and automakers to coordinate and collaborate to deliver a simple to use and seamless experience for EV owners. He points out that major automakers are already planning to incorporate the new J3068 standard and functionality into new models. It adds little cost but results in significantly improved functionality for future EVs.

What next?

The next step would be to establish the interconnection processes for V2G-enabled EVs as well as an easy payment system that would make it worthwhile for EV owners to participate in V2G schemes.  Once that is in place, Kempton says “you just need to have enough EVs” to make it happen to scale. 

This article originally appeared in the April 2024 issue of EEnergy Informer, a monthly newsletter edited by Fereidoon Sioshansi who may be reached at fpsioshansi@aol.com”