Category: Solar Energy (Photovoltaics)
A recent study that specifically focused on the current grid and high-penetration PV called energy storage the ‘ultimate solution’ for allowing intermittent sources to address utility baseload needs. The report stated “a storage system capable of storing substantially less than one day’s worth of average demand could enable PV to provide on the order of 50% of a system’s energy.” This paper focuses on incorporating storage as part of the overall ‘systems’ solution. Successful integration into the larger utility grid infrastructure that include PV-Storage systems will provide many operational benefits to utilities and customers. However, performance of the current battery management systems is limited by the on-board embedded systems as the number of battery cells increases in the large-scale lithium-ion (Li-ion) battery energy storage systems (BESSs). A supervisory control and data acquisition system is still required for integration and maintenance of the large-scale BESSs. Trimark working with SCE has created the Flexible Logic Controller (FLC) to act as an intermediate device to interface the BESS Contractor’s proprietary battery management systems with the multiple interfaces, protocols, and associated control, input, and status points, required for the various applications. The FLC contains control mode algorithms for various applications and will control and monitor the ESS by communicating with the battery management system and other ESS devices through simple, high-level control and status points (e.g., P and Q commands). The FLC provides SCE the ability to revise the control mode algorithms, and control, input, and status points, at a future point in time, without needing to make low-level code changes to the proprietary battery management system, and without requiring the FLC to make changes to proprietary low-level code. The FLC provides the following: • Controllable Distributed Energy Resources combining energy storage, and management with solar PV • Improved predictability of solar PV generation through high resolution solar forecasting • Reduced lifetime cost of solar plus storage system cost through reliable integrated smart inverters • Optimum operation of resources and settings of controllers through distribution feeder modeling and impact studies • Making the grid ready for seamless integration of solar plus storage to support customer choice, while optimizing the electric system: technically and economically • Making solar plus storage more operationally integrated, in a cost competitive manner • Improving the value proposition of solar plus storage and other distributed energy resources.
Scott Barrington– Business Development Manager, Trimark Associates