Provide a summary of your organization’s comments on the issue paper/straw proposal.
The Southwest Public Power Agency (SPPA) appreciates the opportunity to comment on the California ISO’s proposal to establish an EIM Entity Sub-Entity Scheduling Coordinator (SESC) Role.
SPPA is a joint action agency established under Arizona state law, comprising publicly owned, not-for-profit irrigation and electrical districts, municipal electric utilities and tribal utilities. SPPA Members include: Aguila Irrigation District, Ak-Chin Energy Services, Buckeye Water Conservation & Drainage District, City of Safford, Electrical District No. 2 of Pinal County, Electrical District No. 3 of Pinal County, Electrical District No. 4 of Pinal County, Electrical District No. 6 of Pinal County, Electrical District No. 7 of Maricopa County, Electrical District No. 8 of Maricopa County, Gila River Indian Community Utility Authority, Harquahala Valley Power District, Maricopa County Municipal Water Conservation District 1, McMullen Valley Water Conservation & Drainage District, Navajo Tribal Utility Authority, Ocotillo Water Conservation District, Roosevelt Irrigation District, Tonopah Irrigation District, Town of Thatcher, and Town of Wickenburg (the SPPA Members). Additionally, the City of Williams and Tohono O’odham Utility Authority are in the process of becoming members and will likely do so in 2021.
SPPA was formed to give its members a mechanism to jointly manage and dispatch their power resources and pursue more affordable power supply opportunities for the customers they serve. SPPA manages a formal pool of many of its members’ power resources and facilitates the supply of additional energy needed to meet their customers’ loads. The SPPA Members collectively deliver electricity to approximately 880 MW of retail load over an area of 2,100 square miles, mostly in rural Arizona. Many of the SPPA Members are embedded in the service territory of Arizona Public Service Company (APS) and take network transmission service from APS, an EIM entity. SPPA also manages the loads of some members located within the service territories of Salt River Project (an EIM Entity) and Tucson Electric Power and Public Service Company of New Mexico (both of which have announced their intention of becoming EIM Entities).
As an example of the issues SPPA faces, SPPA’s APS members are wholesale entities that interconnect with APS at distribution levels. These entities are intermixed with APS retail customers in rural areas, frequently on the same distribution circuits. SPPA’s APS members have metering comparable to that of APS’s intermingled retail customers. The extant metering satisfies the requirements of the transmission agreements between SPPA and APS, but it likely will not satisfy the metering and telemetry requirements of CAISO Tariff § 29.10, which applies to EIM Entities and is being proposed in this stakeholder proceeding to apply to SESCs. Due to the nature of the metering and the nature of the interconnections, APS allocates many charges—including EIM imbalance charges—to the interspersed retail and wholesale loads on an after-the-fact basis (SPPA understands that this arrangement is similar to that of California Community Choice Aggregators, in the sense that the transmission provider must allocate certain costs among customers of different utility providers).
SPPA’s APS members also take certain scheduling services from APS’s merchant affiliate. Those services have allowed SPPA’s APS members to satisfy their obligations under the relevant transmission agreements and tariffs, including Attachment Q (Energy Imbalance Service) under APS’s OATT. APS has declined to continue providing those scheduling services when the current contract expires, so SPPA will assume those responsibilities on January 1, 2021. SPPA nevertheless expects that APS will continue to allocate charges—including EIM charges—to the interspersed loads of APS’ retail customers and SPPA member wholesale customers in the same way it has always done, without need for expensive metering upgrades that are not required by APS’s transmission agreements with SPPA.
While SPPA has focused on APS as an example, SPPA’s Salt River Project members have a similar situation with loads dispersed within SRP’s territory. SPPA’s PNM and TEP loads will face their own challenges. It will take time for SPPA to be ready to assume an SESC role for its diverse membership, and it may not make sense for some areas to adapt to that framework any time soon. Nevertheless, SPPA expects that it will be in the position of assisting its members in a variety of different system configurations and circumstances. The SESC role, when appropriate, must be flexible enough to accommodate a variety of existing practices that may not always be susceptible to immediate change.
SPPA urges CAISO to clarify, consistent with the general principle that EIM participation is voluntary, that load serving entities have the option of whether to take on the SESC role. The entity that would become an SESC—not the CAISO or the EIM Entity—must have the option.
SPPA also urges CAISO to clarify that this initiative will not expand the EIM metering and telemetry requirements to any entities other than SESCs. If an entity elects not to become an SESC, and where a transmission provider’s tariff and relevant service agreements do not require the same metering and telemetry required by CAISO Tariff § 29.10, then a transmission customer should have no obligation to upgrade its meters. This is especially true for small, local entities that have historically served intermixed loads and been allocated costs without such metering and telemetry, and where it is and likely will remain cost-prohibitive to install more sophisticated real-time metering and telemetry.