Case Studies

Long-Standing California Medical Center Avoids Demand Charges by Rate Switching, Enabled by Solar + Storage

April 27, 2022
Tracy Fosterling

Demand Charge Management

Project Summary

The Challenge

I Love My Solar, a Central California-based project developer, and longtime ETB Developer user, was determined to find a solution for a local medical center wanting to alleviate the increased expense caused by escalating electric rates. The site was billed under the Pacific Gas & Electric (PG&E) B-10 rate, which at the time solar was being considered, had a monthly max demand charge of $13 per kilowatt (kW). Due to continual rate increases, that demand charge has since increased to over $17/kW. Standalone solar was not going to be enough to keep this facility’s max annual peak demand under 75 kW, a requirement of the electric rate that the medical center was interested in switching to.

The Solution

Energy Toolbase’s Acumen EMS™ software was installed alongside a CPS energy storage system (ESS). The primary control applications were demand charge management and time-of-use (TOU) arbitrage. The developer sized the ESS to maximize the medical center’s utility bill savings by rate switching to a rate schedule with lower monthly customer charges and no demand charges. By pairing storage with solar, the customer was able to reduce their demand under the 75 kW max demand threshold, qualifying them for the B-6 rate tariff. The rate switch was enabled by Acumen’s industry-leading machine learning algorithms that utilize historical interval data to forecast load and shave peaks.