The Midcontinent Independent System Operator on Friday proposed a framework requiring large electricity consumers to meet specific ramping and ride-through standards before connecting to the grid. The framework, submitted to the Federal Energy Regulatory Commission, responds to FERC's June directive that major grid operators establish rules for adding data centers and other massive loads to the system. MISO's proposal defines operations with electricity demand above 50 MW as large loads, and those with at least 25 MW from information technology equipment—servers, storage, and networking hardware—as computational loads.
MISO told regulators that average electricity demand grew just 0.5% annually between 2009 and 2024, but the grid operator now anticipates 1% to 2% yearly growth through 2044, with even steeper increases in the near term. The separate computational load classification lets MISO apply targeted requirements to data centers, which the operator says can show sudden and coordinated demand shifts, substantial power-electronic characteristics, and unique reactions to transmission disruptions. The proposal covers four main areas: visibility requirements forcing transmission customers to share basic facility information, modeling data, and real-time load forecasts; phasor measurement unit requirements for high-resolution monitoring; ramp requirements controlling how quickly computational loads can increase or decrease power use; and ride-through requirements setting minimum performance standards during voltage and frequency disturbances.
According to the filing, the interconnection reliability requirements framework aims to improve MISO's visibility into large load "characteristics and behavior, support reliable planning and operational decision-making, and establish scalable and technically justified expectations proportional to demonstrated reliability risk." The grid operator explained that phasor measurement unit data "provides MISO with greater visibility into facility behavior during system disturbances and rapid operating changes, supporting model validation, performance verification, disturbance analysis, and identification of potential dynamic interactions with the transmission system." MISO said managing rapid changes in demand through ramp requirements "helps reduce real-time supply-demand imbalances, sudden change in transmission power flows, and associated operational impacts, while supporting more reliable system operation."
MISO's action follows similar steps at the Electric Reliability Council of Texas and PJM Interconnection after several incidents where data centers abruptly tripped offline, raising worries about grid stability. The proposal addresses these reliability risks by requiring computational loads to maintain minimum performance levels during system events, cutting the chance of unnecessary disconnections or customer-triggered rapid demand reductions. MISO runs the grid and wholesale power markets from Louisiana to Minnesota, and the surge in projected demand growth reflects the region's expanding data center footprint. The framework includes grandfathering provisions to protect existing and nearly complete commercial arrangements for large loads.
MISO asked FERC to approve the proposal for a Dec. 4 effective date and said it plans additional filings by a Nov. 16 deadline. Those future proposals will address extra transmission products and study processes, protections against cost shifts, and the treatment of generation service to electrically proximate large loads. The framework's real-time and day-ahead forecasting requirements give MISO the information needed to conduct planning studies, operational assessments, and accurate modeling of how large loads affect the system—tools the operator says are essential as demand growth accelerates beyond the flat trends of the past 15 years.