Midcontinent Independent System Operator (MISO) states should seize the opportunity afforded by the regional transmission organization (RTO) in its Expedited Resource Addition Study (ERAS) proposal and prioritize energy storage as ERAS-eligible. MISO states are key in implementing ERAS to address resource adequacy issues. MISO plans to file its ERAS proposal with the Federal Energy Regulatory Commission (FERC) in mid-March. This would be the perfect opportunity to interconnect energy storage resources faster at MISO much like California and Texas.
MISO’s ERAS Proposal Background
MISO’s ERAS proposal was first discussed in November 2024 at the MISO Planning Advisory Committee (PAC). MISO proposes the ERAS process as a short-term solution to address capacity concerns until the queue backlog and study timeline are reduced. MISO wants to expedite projects sitting in the queue waiting to be studied under this ERAS proposal with consent from MISO participants. The MISO queue currently has 1,705 projects waiting to be studied with a total capacity of 312 gigawatts (GW). In contrast, MISO has an installed capacity of 202 GWs.
Without this proposal, MISO must continue to clear the backlog from previous queue cycles and work towards projects submitted in the 2023 cycle. Due to the large volume of projects sitting in the queue, MISO did not open the 2024 queue cycle, and the 2023 cycle was opened in March 2024, rather than September 2023. For renewable developers, MISO’s ERAS proposal is good news because MISO plans to evaluate the projects on an individual basis, not in a cluster. However, ERAS also demands several requirements including stringent site control, large milestone payments, state acknowledgment, and three-year commercial operation.
MISO’s ERAS Proposal Requirements
To be ERAS-eligible, developers must first have 100% site control.
Secondly, in addition to a non-refundable application deposit fee of $100,000 ($7,000 for projects going through the normal queue cycle), MISO is collecting $24,000 per megawatt (MW) as a second milestone (M2) payment. In contrast, the current M2 milestone payment is $8,000 per MW. This ERAS proposal ensures that only the most serious projects with financial backing can move forward, making it a premium fast-track option.
Third, MISO will require direct acknowledgment from states in this ERAS proposal. MISO insists state regulatory authorities must acknowledge the resources that they wish to prioritize for resource adequacy purposes in this ERAS proposal.
The fourth and final requirement for MISO’s ERAS proposal is that the project must enter commercial operation within three years.
MISO States concerns
MISO insists that for ERAS to work, projects must be recognized by their state regulatory authorities. The Arkansas Public Service Commission (APSC) was among the state commissions that submitted direct comments to MISO. APSC’s main concern is that MISO should have an ERAS proposal that fits different state priorities and criteria and MISO should not have a one-size-fits-all approach towards ERAS. APSC states that MISO should allow flexibility in attestation qualification requirements and not automatically sunset ERAS. MISO is currently proposing a sunset date of December 31, 2028, for ERAS, which means MISO will no longer offer ERAS as an option for states to prioritize resources needed for resource adequacy purposes beginning in 2029.
Organization of MISO States (OMS) Transmission Planning Work Group and Resources Work Group jointly commented. The OMS Work Groups’ main concern is that the ERAS process must remain a temporary stop-gap measure and should not distract from or replace efforts to improve MISO’s existing generation interconnection queue, which should remain the primary solution for resource adequacy. They emphasize the need for sufficient guardrails, transparency, and additional time for stakeholder input to avoid potential legal challenges and ensure broad state support.
Energy Storage is an ideal ERAS-eligible resource
Energy storage projects should be prioritized in this ERAS proposal because they can provide much-needed capacity for resource adequacy in multiple MISO States. One of the reasons behind higher storage penetrations in California Independent System Operator (CAISO) and Electricity Reliability Council of Texas (ERCOT) territories is the capacity value that storage provides. Both CAISO and ERCOT have taken steps to address their capacity concerns by interconnecting storage projects much faster. If MISO wants to address its looming resource adequacy concern, storage should be allowed to play a major part.
ERAS is the right proposal for storage because, without ERAS, storage projects will be sitting in the queue waiting to be studied for three more years when the 2024 OMS MISO Survey is showing MISO could have a capacity shortfall of 2.7 GW or a surplus of 1.1 GW depending on the amount of generation MISO could interconnect.
While the OMS Work Group’s comments focus on procedural safeguards, they overlook a key opportunity: energy storage can immediately support resource adequacy and should be prioritized. MISO’s latest Regional Resource Assessment report suggests there is a growing need for fast-ramping resources at MISO beyond 2030. MISO’s RRA analysis suggests that four-hour batteries no longer provide the capacity value that long-duration batteries do in those years beyond 2030.
MISO’s ERAS proposal sunsets in 2028. Energy Storage projects sitting in MISO’s queue are mostly four-hour-duration batteries, either at solar or wind sites. That’s why MISO states should first prioritize the storage that is sitting in the queue rather than postulating that MISO’s queue should be a priority. Some might argue that MISO’s long-term need is for long-duration storage beyond 2030. However, the immediate concern is addressing near-term reliability needs, and four-hour batteries are well-suited for that.
MISO’s queue should always be a priority, but MISO is unable to study all the projects in the queue because of the huge backlog. While improving MISO’s queue remains a priority, the sheer magnitude of 1,705 projects makes it impossible to process them all in time to meet urgent capacity needs in the next 3 years. Unless MISO prioritizes and flushes out the serious projects stuck behind less serious projects, the queue will remain unmanageable. This is one shot for MISO to clear out the queue.
next steps
MISO is planning to file its ERAS proposal at FERC next month. This is a fast-paced proposal for states to get behind, but if they speak in a common voice at FERC when filing their responses after MISO files its proposal, the current FERC Chairman Mark Christie and his fellow Commissioners are unlikely to reject MISO’s proposal.
MISO and MISO participating states are essentially driving this resource adequacy train with renewable developer’s consent. MISO States should act now and push for energy storage to be prioritized under ERAS. Without decisive action, the next capacity crisis could be entirely avoidable—but only if they seize this opportunity.
