​MISO has 784 MW of operational BESS and 49 GW in its interconnection queue. Applying historical completion rates and accounting for project delays, Modo Energy projects 2 to 5 GW operational by 2030. Development concentrates in MISO North, where Michigan and Illinois hold the largest pipeline shares.

Key Takeaways

• MISO will have a base of 2 GW of BESS by 2030 with an upside of 5 GW of installed capacity. This represents 3-6x growth from today but captures just 4-10% of the 49 GW queue.
• MISO North will capture most new capacity. Michigan and Illinois hold 88% of the pipeline.
• Developers targeting 2030 must clear Phase 3 in 2026. Every completed BESS project in MISO has missed its original commercial operation date by a median of 36 months.

Modo Energy projects 2 to 5 GW of BESS by 2030

Applying historical completion rates to MISO's queue yields 2 to 5 GW by 2030. BESS has the lowest survival rate of any fuel type at 5.9%, compared to 22% for all fuels.

Modo Energy derived these projections by analyzing all 3,701 projects (657 GW) in MISO's interconnection queue. The analysis covers withdrawn, active, and completed projects across all fuel types.

The projection also accounts for timing. Every completed BESS project in MISO missed its original commercial operation date. Median delay is 36 months. Only 44% of the current queue (21 GW) has original COD dates early enough to reach 2030 after typical delays. Therefore, projects targeting 2028 or later original CODs may slip into 2031.

The base case (2 GW) applies BESS-specific survival rates to this timing-adjusted pool. The upper bound (5 GW) assumes BESS execution improves toward market norms as DPP reforms take hold.

How much BESS capacity sits in MISO's queue?

MISO's BESS queue totals 49 GW across all study phases. However, the pipeline concentrates in early-stage development.

Of this total, 22 GW has not yet been assigned to a study cycle. Another 8 GW sits in the Study Not Started category. Phase 1 and Phase 2 together account for 16 GW in active studies under MISO's Definitive Planning Process (DPP).

Only 9 GW has reached Phase 3 or secured a Generator Interconnection Agreement (GIA). The credible near-term pipeline is 80% smaller than the headline figure.

Where is MISO's BESS pipeline concentrated?

MISO North holds 88% of queued BESS capacity. MISO South holds 12%. This imbalance will shape competitive dynamics through the end of the decade.

Michigan and Illinois represent the largest pipeline shares. These states benefit from wholesale price volatility, proximity to constrained transmission interfaces, and state-level clean energy policy.

MISO South's limited pipeline reflects regional priorities. Southern utilities have focused on natural gas through the ERAS program rather than standalone storage. Lower inverter-based resource penetration also means weaker arbitrage signals. Across MISO, merchant activity remains limited compared to ERCOT, CAISO, or PJM.

The concentration creates both opportunity and risk. Developers with early positions in Illinois and Michigan face favorable market conditions but increasing competitive intensity. Those targeting MISO South face lower queue congestion but weaker price signals.

Which states lead in operational BESS?

MISO's operational BESS fleet stands at 784 MW across 34 projects. For comparison, ERCOT has 14 GW and CAISO has 13 GW.

Indiana holds the largest share at 337 MW across 8 projects. Wisconsin follows with 281 MW, then Michigan with 115 MW.
In contrast, MISO South holds just 2% of operational BESS capacity. Arkansas accounts for 16 MW with minimal activity elsewhere in the south.

When will new BESS capacity come online?

Proposed COD dates show 2028 as the largest wave of scheduled BESS additions. However, the universal delay pattern means few projects will hit original targets.

The 2025 additions marked the first year of significant MISO BESS integration. Total battery energy storage capacity grew 366% during the year, from 176 MW to 784 MW.

MISO's buildout is shifting from utility-led pilots to concentrated pipeline development in MISO North. Therefore, developers targeting 2028-2030 CODs face a narrowing window. Projects that clear Phase 3 in 2026 will set the benchmark for merchant BESS economics.

What does this mean for developers?

Even at the upper bound, 5 GW of BESS by 2030 represents 4% of MISO's 130 GW peak demand. However, BESS plays a reliability role that exceeds its nameplate contribution. Storage provides fast-ramping capacity during tight conditions, absorbs renewable curtailment, and relieves transmission congestion at constrained interfaces.

The path forward: secure queue positions in MISO North, clear Phase 3 by 2026, and plan for 3-year delays. The 5.9% BESS completion rate shows that DPP reforms have not yet solved the underlying barriers to merchant storage deployment.