Telematics-Based Managed EV Charging: A Pilot Case Study for Utility Bulk and Distribution Grid Services

<div class="section abstract"><div class="htmlview paragraph">Growth in the EV market is resulting in an unprecedented increase of electrical load from EV charging at the household level. This has led to concern about electric utilities’ ability to upgrade electrical distribution infrastructure at an affordable cost and sufficient speed to keep up with EV sales. Adoption of EVs in the California market has outpaced the national average and offers early insight for other regions of the United States. The Sacramento Municipal Utility District (SMUD) partnered with two grid-edge Distributed Energy Resource Management System (DERMS) providers, the OVGIP (recently incorporated as ChargeScape, a joint venture of Ford, BMW, Honda, and Nissan) and Optiwatt, to deliver a vehicle telematics-based active managed charging pilot. The pilot program, launched in Summer 2022 enrolled approximately 1,200 EVs over two years including Tesla, Ford, BMW, and GM vehicles. The goal of this pilot program was to evaluate the business case for managed charging to mitigate EV grid impacts and deliver additional grid services, providing value to both EV drivers and the electric utility. The grid services tested included reducing bulk electrical system peak load, reducing service transformer overloads, and increasing consumption of solar generation to reduce solar curtailment. Sacramento-specific day-ahead dynamic energy prices were used as an optimization objective to influence daily optimized charging schedules unique to each EV. A randomized control trial (RCT) was used to measure program effects compared to a no-program scenario. A combination of statistical Energy Measurement & Verification (EM&V) techniques and Monte Carlo simulations were used to evaluate performance extrapolated to a future grid and EV adoption scenario in 2030. The detailed experiment design, analysis methodology, and preliminary grid service performance results will be presented in this paper. Customer survey results indicating customer acceptance of managed charging and opportunities for improvement will also be shared.</div></div>