With the rise of smart grid technologies, the utility industry is increasingly talking about the future of DSM (demand side management) and DER (distributed energy resources) generally, and EV load management specifically. What future developments are coming to help manage EV load, when will they arrive, and what impact could they have? Your utility already has EVs to manage: can any of these solutions help today?
One of the most commonly discussed future developments is the Open Vehicle-Grid Integration Platform (OVGIP) developed jointly by the Electric Power Research Institute (EPRI) and the auto industry. Also called "in-car telematics", OVGIP is designed to allow two-way communication between plug-in vehicles and the grid using a shared communications protocol. This means utilities could see charging activity, battery percentage or call demand response events for vehicles located in a specific area, regardless of where those vehicles "live" or what kind of charger they are using. The main challenge of the OVGIP model is that it relies on automakers to integrate the protocol in to their vehicles, which has not happened yet. It also requires that utilities have an active smart grid system capable of two-way communication and calling DSM events (with or without human intervention). Vehicles currently on the road are not likely to be backwards compatible, unless more automakers embrace the over-the-air updates pioneered by Tesla. The OVGIP protocol was published in 2016, but has yet to be implemented in any active programs that we are aware of.
The other hot topic is Vehicle to Grid (V2G). A V2G system would pull energy from vehicle batteries and feed it back in to the grid, actively reducing demand during peak events. It seems like a slam-dunk! EVs commonly have charging capacities of 6-10kW, and being able to call that level of power to the grid on demand could be a game changer. However, there are several major hurdles to widespread V2G adoption. First of all, only the Nissan LEAF is currently available with V2G capabilities, with no indication that other manufacturers have plans to follow suit. By charging and discharging the battery more frequently, the usable life of the most expensive part of the vehicle will be shortened. It isn't clear that the demand response benefits outweigh the wear and tear to the system. There are no commercially available EV charging stations with V2G capabilities either. The challenges of V2G may be solved, but certainly not in the next few years.
With these challenges in mind, what can utilities do about EV load management today? The most common solutions seem to be time of use rates, and smart charger programs. However, in our experience, and the experience of utilities around the country, these programs are expensive and have very low market penetration rates. Like the future solutions discussed above, unless an EV load management program can reach a significant percentage of EV load, it isn't an effective solution. Bring Your Own Charger was developed to work with any vehicle and any home charger. Future solutions like OVGIP may eventually be more powerful, and able to only control charging when needed, BYOC is available today and can manage significant EV charging load.
