While the rise of electric vehicles (EVs) represents a significant energy sales and decarbonization opportunity for utilities, it also poses formidable capacity and stability risks to the grid. The load required to charge EVs, their tendency to be adopted in pockets, and the unique charging behaviors of customers will result in significant threats to utilities. EVs will continue to exacerbate the load balancing and management challenges that utilities are facing today with the proliferation of renewables.
However, as more customers install residential charging solutions and allow their utilities some degree of control over them, the risks to the grid can be mitigated over time. It is increasingly critical that utilities adopt solutions that can monitor and control EV charging in real-time, both to mitigate the distribution challenges posed by EVs unconstrained operation and to leverage their potential as flexible assets.
EnergyHub has released a new whitepaper in partnership with ChargePoint, analyzing experiences and best practices in utility EV management programs. You can download the whitepaper here and read on for a summary.
Residential EV charging is inherently flexible
Insights gleaned from analyzing data from ChargePoint’s Level 2 chargers confirms that residential EV charging behavior provides flexibility for managed charging. EV drivers typically get home from work and plug in their car for the following day. On most days, the EVs do not require a full charge - despite being plugged in for over 10 hours, on average, an EV battery is actively charging only for a little over two hours. This concentrated charging in a short time window results in a sharp peak in the evening. On the flip side, this also indicates that utilities have a window of over eight hours to stagger charging to prevent this peak.
Three phases of EV management
In order to tap into this flexibility, utilities across the US are launching customer-centric EV management programs. While these programs vary in terms of level of control and associated use case(s), a phased approach holds the promise of future scale. Utilities are adopting a phased “crawl, walk, run” approach, as shown in the figure below, to better understand EV charging behavior, which informs the development and iteration of managed charging solutions.
The crawl phase is to enable EV-specific time-of-use (TOU) rates. TOU rates are designed to incentivize customers via rebates to move charging away from peak times. To operationalize TOU programs, utilities are implementing platforms that can not only gather EV charging data and track related incentives, but also support the marketing of the rates to customers and subsequently provide robust reporting on the efficacy of the rates. Baltimore Gas and Electric for instance, has deployed EnergyHub’s Mercury DERMS to lay the foundation for their upcoming EV-TOU rate. However, while TOU and critical peak pricing can be an effective first step to shaping load behaviorally, the coarse price signals they send are insufficient to prevent coincident charging.
The walk phase is event-based peak management. Analogous to the evolution of demand response from behavioral and rate-based usage recommendations to active thermostat control, this phase entails customers providing utilities limited access to modulate the rate of charge
in exchange for a financial incentive. Once the utility has access to EV chargers through a DERMS platform, it can schedule point in time events for peak reduction by curtailing and intelligently staggering the charging. Eversource, for instance, has launched an innovative new EV management program, by applying the bring-your-own-device (BYOD) model to EV chargers. Through this deployment, Eversource has access to customer charging data and the ability to control residential charging across its service territory at peak times.
The run phase refers to a more dynamic approach to shaping load. This entails optimization of EV charging that takes into account real-time customer, grid and market constraints. In this phase, the utility optimizes charging patterns multiple times a day, potentially in concert with other DERs, in a way that delivers stacked value for the utility. This could help meet more complex utility needs such as congestion management, renewable firming, and voltage management.
Leveraging a DERMS to prevent another operational silo
Utilities across the U.S. are exploring various solutions to operationalize EV charging management programs. Some are deploying point-solutions that are EV-specific, while others are taking a more forward looking approach by adopting DERMS as an ideal solution to unlock EV-enabled grid and customer value. A distributed energy resource management systems (DERMS) platform is the ideal solution to empower utilities to unlock these EV-enabled network, market, and customer opportunities in concert with other DERs and grid assets.
As utilities explore the crawl, walk, run approaches to manage charging, they should deploy a solution that can scale and advance at their pace. The Mercury DERMS is a platform built to support the dynamic and iterative nature of EV programs. It enables customer choice, manages multiple brands and classes of DERs at scale, and integrates with complementary utility systems to unlock value across the utility value chain.
Interested in learning how EnergyHub can help you achieve your goals for EV management? Download our EV charging factsheet.