MISO: Midcontinent Independent System Operator

MISO operates the electricity grid across 15 states and one Canadian province, from Minnesota to Louisiana. The grid is undergoing a major transformation with aggressive transmission expansion plans to enable clean energy integration across the Midwest.

Coverage Area

MISO's footprint extends from Minnesota and the Dakotas through Iowa, Wisconsin, Michigan, Illinois, Indiana, and down through Missouri, Arkansas, Mississippi, Louisiana, and parts of Texas. This north-south orientation creates opportunities for geographic diversity in renewable generation but also transmission planning challenges.

Long Range Transmission Planning (LRTP)

MISO has embarked on the most ambitious transmission expansion in US history through its Long Range Transmission Planning initiative. The first tranche, approved in 2022, includes 18 projects totaling approximately $10 billion in investment. Additional tranches are under development to enable the retirement of aging coal plants and integration of new renewable resources.

These transmission investments are expected to deliver over $40 billion in benefits through reduced congestion, improved reliability, and access to lower-cost generation. The LRTP process represents a model for regional transmission planning that other RTOs are watching closely.

Wind Energy Integration

MISO has integrated more wind energy than any other grid operator in the US, with over 30 GW of installed capacity. Iowa alone often generates over 60% of its electricity from wind. The region's excellent wind resources, combined with available land and transmission expansion, continue to attract significant development.

Capacity Challenges

MISO has faced capacity adequacy concerns as coal plant retirements accelerate while new resource additions—particularly dispatchable resources—lag. Capacity auction prices spiked in 2022, raising concerns about resource adequacy during the energy transition. MISO has implemented seasonal capacity requirements and is exploring market reforms to address these challenges.

State Policy Diversity

MISO's territory includes states with vastly different energy policies, from Minnesota and Illinois with aggressive clean energy targets to southern states with more fossil-dependent economies. Managing this diversity while maintaining a cohesive wholesale market is an ongoing challenge.

Frequently Asked Questions