Nodal Protocol Revision Request (NPRR) 560, Caps and Floors for Energy Storage Resources, initially introduced the concept of an Energy Storage Resource Category to establish cost caps for storage technologies, such as Compressed Air Storage Resources. To reduce the impact to ERCOT systems of creating a new Resource category, it was decided to utilize the verifiable cost process to implement the various caps and classify all Energy Storage Resources as “Other”, which in the current Protocols have $0/MWh as the Energy Offer Curve Cap for make-whole calculations. The Energy Offer Curve Caps for make-whole calculations for Energy Storage Resources was described in the Verifiable Cost Manual as not having a cap, while in the Protocols these new types of Resources are classified as “Other”, with an Energy Offer Curve Cap for make-whole calculation of $0/MWh. Clearly, this was an oversight since ERCOT cannot calculate Energy Offer Curve Caps for make-whole calculations without a system change. This NPRR tries to rectify this oversight by setting the Energy Offer Curve Caps for make-whole calculations for “Other” Resources to the System-Wide Offer Cap (SWCAP), which is consistent with what was approved for Energy Storage Resources as not having a cap. Furthermore, ERCOT shall report annually to TAC or an assigned TAC Subcommittee the percentage of DAM and RUC Make-Whole Payments calculated for Resources classified as “Other”.
In addition to the changes described above, a Resource category for Wind Generation Resources and PhotoVoltaic Generation Resources (PVGRs) have been created. ERCOT systems currently have a separate category for Wind Generation Resources with an Energy Offer Curve Cap for make-whole payments set at $0.00/MWh. We have included this category in this NPRR to align the Protocols with the current methodology ERCOT systems utilize. With the implementation of NPRR588, a PVGR category will be created with an Energy Offer Curve Cap for make-whole payments set at $0.00/MWh. The PVGR category has been included in this NPRR as a clarification for the methodology that will be used once NPRR588 is implemented.