Novel Battery Augmentation Strategy Via Hybridization with Long-Duration Energy Storage Technology

The transition to variable renewable energy requires new approaches to provide grid reliability. Lithium ion (Li-Ion) batteries can contribute to reliability, but capacity degradation needs to be accommodated through overbuild and/or augmentation throughout the life of the plant. An alternative strategy is augmenting a Li-Ion battery plant with a long-duration energy storage (LDES) technology in parallel to the existing batteries. Installing parallel technologies would create a hybrid storage plant that can accommodate shifting use cases required by the grid like widening net-peak load periods. This study used software from Storlytics to model the degradation of batteries and EPRI's Distributed Energy Resource Value Estimation Tool (DER-VET) to find the optimal dispatch of energy storage. The approach compared strategies based on potential profitability in the context of historical electricity prices from a node in Zone 7 of the Midcontinent Independent System Operator. The study compares the benefits of hybridizing batteries with LDES technologies such as vanadium flow, liquid carbon dioxide, compressed air, and pumped heat.