The US electric grid is undergoing rapid change driven by electrification, energy-intensive new loads, extreme weather, ageing infrastructure, and a shifting generation mix. Meeting these challenges will require significantly more and higher-capacity transmission. Against this backdrop, the Energy Systems Integration Group (ESIG), formerly known as the Utility Wind Integration Group (UWIG), has released a new report addressing growing concerns over how fragmented transmission planning practices are hindering grid development in the US. The report, titled ‘Modernizing Transmission Planning: Integrating Silos to Deliver Multi-Driver, Multi-Value Outcomes’, assesses current planning practices, explaining what today’s siloed planning produces, why it persists, and how existing tools and processes can be better aligned to meet long-term reliability, resilience, and policy needs.

The report finds that most regions still plan transmission through parallel tracks – generator and load interconnection, reliability, economic congestion, asset management, public policy, and large-load planning – each with its own timelines, assumptions, and analytical methods. While coordination occurs, it is typically ad hoc, resulting in lower-voltage, narrowly scoped upgrades that address near-term local problems but add little regional transfer capability. Over time, this approach underutilises corridors, drives up costs through serial mitigations, increases interconnection queue churn, and leaves the system reactive rather than forward-looking. To address these shortcomings, ESIG proposes an ‘integrate, broaden, deepen’ framework, which links planning silos through shared assumptions and hand-offs, expands the scope of drivers and futures considered, and strengthens analytical rigour so portfolios are operable, scalable, and designed for multiple needs from the outset. Key priorities include

  • Integrate interconnection with long-range planning: Use common futures and constraints across studies, group compatible requests, convert recurring bottlenecks into shared corridor upgrades, and reflect high-interest queue areas and load-interconnection zones in expansion plans.
  • Integrate asset replacement with long-term needs: Make right-sizing the default and bundle overlapping rebuilds with nearby system constraints so one corridor upgrade avoids repeated construction and delivers durable transfer capability.
  • Integrate operations with planning: Incorporate ramping, stability, inertia, voltage, and weak-grid conditions early; formalise operator input; use production-cost stress periods; and apply transient analysis when needed.

By not adopting reform, transmission planning risks continuing a cycle of undersized or stranded investments, missed opportunities to maximise existing rights-of-way, and rising costs alongside elevated reliability and resilience risks. With the implementation of FERC Order 1920 now underway, ESIG argues that the conditions are in place to move from parallel planning tracks to recurring, integrated planning cycles that deliver multi-driver, multi-benefit transmission portfolios. By making integration, broader scenario development, and deeper analysis routine, planners and policymakers can ensure that new transmission investments provide lasting value and position the US grid to meet the demands of a rapidly evolving energy landscape.

The full report can be accessed here.