Category: Energy Storage
Background/Problem Statement: DC coupled Energy Storage System (ESS) systems today adds much needed flexibility and control for PV power to be utilized for time of use, demand management, self-consumption, home backup, and stand-alone operations. However, one of the biggest challenges with existing DC coupled ESS solutions is the limitation on backup loads that customers can “backup” in a grid outage situation. Consumers are limited with critical backup loads that they choose during initial system installation and cannot utilize “other loads - not backed up” if requires when operating under “backup mode”. This acts as a major concern for residential ESS consumers today, as the present architecture does not provide them the flexibility to use all circuits on the main distribution panel and prioritize loads based on the available storage capacity.
Description/Solution: Available solutions in the market today are focused on increasing system size to backup the entire main panel in a grid outage situation. A solution like this is expensive, oversized, underutilized and would still not provide customers the information to make their own decisions in a grid outage situation. Q-Cells is developing a truly differentiated architecture that removes the need for a backup panel by integrating smart controls into the ESS architecture. The proposed system monitors energy production (solar), storage capacity and load consumption to offer flexible and priority-based load control in a grid outage situation. Using this architecture, the residential main panel will be backed up and users can make informed decisions on what loads they want to power following available storage capacity. This system architecture is expected to improve user controllability (experience) and reduce total installation costs through less components in the system design.
Results: The talk with provide an overview of the proposed solution, system level architecture, use case and discuss advantages of this configuration over existing solutions. Balance of system (BOS) cost, system loss, data communication framework for this architecture will be presented and compared to existing solutions currently available. Detailed results on system performance, resiliency and usability under “home backup” mode will also be presented. Besides the home backup, designed system will also be able to communicate with the utility or the aggregators providing grid support through intelligent load control during normal grid-tied operation.
Tanvir Khan– Senior ESS Engineer, Q CELLS