Transmission Planning as the New Bottleneck
The U.S. energy transition is no longer constrained by technology. Solar, wind, and storage costs have plummeted. Demand from data centers, hydrogen, and electrification is skyrocketing. Policy support is strong.
But transmission, the high-voltage backbone of the power system, remains the Achilles’ heel. Without new lines, renewable projects stay stranded in interconnection queues, storage can’t be dispatched efficiently, and large loads face higher costs and reliability risks.
By 2026, transmission planning in the U.S. will look fundamentally different than it does today. Federal directives (FERC Orders 1920 and 2023), ISO/RTO reforms, and state policies are converging into a new model of long-term, large-scale planning.
Takeaway 1: Longer Transmission Planning Horizons Are the New Norm
Traditionally, transmission planning looked 10 years out. By 2026, expect 20- to 30-year horizons to become standard. ISOs like MISO, SPP, and CAISO are already embedding multi-decade scenarios into their planning frameworks.
Why It Matters:
- Wind and solar developers get better signals about where capacity will open in 2030–2040.
- Storage developers can align duration and siting with future congestion trends.
- Large-load customers (data centers, hydrogen) can see where long-term backbone capacity will materialize.
For developers, this means project pipelines must adapt to longer visibility but also longer uncertainty.
Takeaway 2: Bigger Backbones Are on the Table
High-voltage buildouts once considered “too ambitious” are now becoming reality. By 2026, we’ll see serious movement on 765 kV AC backbones and HVDC corridors.
- MISO: Advancing a 765 kV north-to-south backbone.Read more about MISO’s 765kV Backbone here.
- SPP: Studying multi-state HVDC lines.
- PJM & NYISO: Exploring offshore wind HVDC “meshes” to connect gigawatts of capacity.
Why It Matters:
Utility-scale solar and wind projects in remote, resource-rich areas will finally have transmission pathways to demand centers. But these projects also come with decade-long build timelines, meaning developers must remain patient and strategic.
Takeaway 3: Data Center Growth Is Reshaping Priorities
Hyperscale data centers — especially in PJM, MISO, and ERCOT — are emerging as the biggest single load driver. By 2026, expect data center demand to shape transmission planning as much as renewables.
- Data center clusters in Virginia, Ohio, and Iowa are already dictating substation upgrades.
- Renewable developers are both competing with and benefiting from these load hubs, since proximity to large-load interconnections can improve deliverability.
- Hydrogen hubs and industrial loads will also influence planning as federal incentives scale up.
Transmission is no longer just about moving renewables to load; it’s also about serving massive new loads directly.
Takeaway 4: Policy Alignment Is Driving Cohesion
Until recently, federal, state, and ISO/RTO policies were often misaligned. By 2026, FERC Orders and DOE initiatives are pushing toward a more unified approach:
- FERC Order 1920: Mandates longer-term, multi-scenario transmission planning.
- FERC Order 2023: Standardizes interconnection reforms across ISOs.
- DOE Initiatives: Transmission Facilitation Program and “Speed to Power” RFI support large-scale expansion.
Why It Matters:
Projects that align with state and federal goals, offshore wind in the Northeast, solar + storage in the West, hydrogen in the Midwest, will see transmission prioritized. Developers who ignore policy signals risk siting in zones with no long-term capacity.
Takeaway 5: Developer Engagement Is No Longer Optional
Historically, transmission planning was a utility/ISO exercise, with limited developer input. By 2026, developers will need to engage actively in planning processes to ensure their projects are considered.
- Solar & wind developers can advocate for corridors that unlock stranded resources.
- Storage developers can highlight how strategically sited batteries reduce upgrade needs.
- Large-load customers can negotiate with ISOs for transmission that enables their growth.
For merchant developers especially, staying passive in planning forums is no longer viable. Transmission is now a competitive space, and early influence matters.
Risks to Watch
- Permitting & Siting Battles: Even as planning advances, new lines face local opposition and multi-year delays.
- Cost Allocation Disputes: Who pays for $20B+ regional buildouts will remain contested between states, utilities, and developers.
- Timeline Realism: Many announced projects won’t break ground until the 2030s, creating a mismatch between developer needs and transmission delivery.
ZEG’s Perspective
At ZEG, we like to believe transmission planning in 2026 will be defined by scale, policy alignment, and load growth. Developers should treat planning signals as guideposts, not guarantees.
- Utility-scale renewables: Look for corridors where 765 kV and HVDC are advancing.
- Storage developers: Target nodes adjacent to planned backbones, where storage can capture congestion value.
- Data centers and hydrogen developers: Use planning outputs to choose sites with reliable, affordable power access.
The key is early positioning. Waiting until lines are approved means missing the window of opportunity.
Transmission as Strategy
By 2026, transmission will no longer be an afterthought, it will be a central part of development strategy. Developers who treat transmission planning as a market signal will unlock opportunity. Those who ignore it will face delays, curtailment, and higher costs.
The U.S. energy transition depends on this buildout. For developers, the message is clear: transmission is the new frontier.
Learn more about FERC orders and initiatives here.
