PJM Interconnection LLC filed revisions with the Federal Energy Regulatory Commission for market rules that would provide greater flexibility for energy storage resources participating in the wholesale market to manage system operations when charging, discharging or providing continuous electrical service across their full dispatchable range. PJM said the proposal includes modifications, where necessary, to the capacity, energy and ancillary services markets. In the capacity market, these sources may choose to participate as a stand-alone resources or combine capabilities with other eligible resources to form an aggregate resource. In the energy market, storage resources can switch between continuous, charge, and discharge modes. The proposal follows the Federal Energy Regulatory Commission’s Feb. 15 order that requires grid operators to establish a participation model for electric storage resources. The filing includes an accounting proposal for which PJM seeks approval by Feb. 3, 2019, to provide enough time to test its proposed metering and accounting practices, and gain real-world experience to address challenges, before implementing the new model. PJM requests a decision on the remainder of its participation model by May 30 to prepare for the Dec. 3, 2019 effective date.