Director, Energy Storage Intertek Canyon Lake, Texas
Presentation Description: As with any other grid-connected asset and large financial investment, it is important to understand how battery energy storage systems (BESS) work, what the potential failure mechanisms are, the expected frequency of those failures, and any mitigative or corrective actions that can help to prolong asset life. This presentation presents a case study demonstrating how operational changes to a BESS can impact asset life. In January 2017, PJM reengineered their RegD signal for fast-response frequently regulation resources after finding problems with the original signal design. As a result, batteries are essentially operating twice as long and are subject to higher energy exchanges with the grid, beyond the bounds for which they were originally designed. This has led to accelerated degradation and aging of RegD resources. This presentation evaluates how the RegD signal change affected the operation of one battery resource operating in PJM and introduces out energy storage system model for life assessment. Assessing and projecting battery life is difficult. Regular BESS performance testing is needed to track capacity fading; reliable testing takes a lot of time and requires the system to be offline. As an alternative to regular performance testing, Intertek AIM has developed an empirical model that can quantify battery damage based on its performance. Our preliminary model weights damage due to the depth and rate of battery cycles and uses a rainflow cycle counter to quantify that damage in terms of equivalent cycles.
describe the failure runaway process
describe the PJM RegD signal change and battery understand its impact on expected battery life