Electricity Is Cheap. Moving It Is Not.

Solar panels and turbines can be manufactured by the million. A transmission corridor is negotiated one landscape at a time. As generation gets cheaper, the scarce product is increasingly permission and time to move power.

Last updated September 2026
Figure 1 · Four ways to create transfer capacity

The corridor is often the scarce asset

Advanced reconductoring

A low-sag, high-temperature conductor can put substantially more aluminium on an existing route without rebuilding every tower. It turns the hardest-won part of a line—the corridor—into reusable infrastructure.

Capacity effect
Up to roughly 2×
Deployment
About 1–3 years where feasible
Land requirement
Keeps towers and right-of-way

Limit: Tower strength, clearances, substations, outages, and downstream equipment can cap the usable uplift.

Ranges describe categories, not project quotations. Actual capacity, cost, and schedule depend on voltage, topology, equipment limits, outages, terrain, and the approvals a project requires.

What the record shows

  • At the end of 2025, 2,061 GW—1,312 GW of generation and 749 GW of storage—was actively seeking U.S. transmission interconnection, down 10% year over year and 21% from the 2023 peak of 2,598 GW (Measured).
  • Only 13% of capacity requesting interconnection from 2000 through 2020 had reached commercial operation by the end of 2025; 75% had withdrawn (Measured).
  • The median time from request to operation was about 22 months for projects built in 2008, 36 months for 2015, and 61 months for projects completed in 2025 (Measured).
  • A review cited by the U.S. Department of Energy found new transmission projects take about ten years on average. Existing corridors can sometimes be upgraded in one to three.

Queue capacity is measured developer interest, not expected completion. Technology uplift is conditional, not additive. Timelines describe observed or reported classes of projects, not a promise for any individual line. Evidence labels used here: Measured (directly demonstrated), Derived (calculated from measured data), Projected (modeled future outcome), Target (announced goal), and Editorial inference (interpretation of evidence).

Part I: The new scarcity

Electricity can be cheap and still be stranded

A generator produces at a node, not everywhere. Its economic output is the energy that can cross the network after losses, operating limits, contingencies, and congestion—not the energy it could produce in isolation.

That distinction becomes decisive when wind and solar equipment gets cheaper and faster to deploy than the network around it. A low bid at a windy site is not a delivered price to a city. The missing terms include interconnection upgrades, substations, long-distance transfer, congestion, curtailment, reserves, and the years during which capital waits for access.

Generation+Network + congestion+Time and curtailment

The unit that matters is commissioned transfer

~10 yearsAverage end-to-end duration in a DOE-cited review of more than 30 new transmission projects.
1–3 yearsReported deployment window for many grid-enhancing technologies and feasible reconductoring projects.
20–64%Median additional within-region deployment need by 2035 in DOE's moderate- and high-clean-energy scenario groups.

Cost per mile hides voltage and power. Cost per megawatt-mile is better, but still ignores utilization and schedule. The most revealing ledger records dollars, firm transfer capability, congestion relieved, and years to energization together.

Part II: The queue

A waiting list became a market signal

Interconnection studies determine the network upgrades required to connect a proposed plant and who initially pays for them. As requests multiplied, a serial engineering process became a portfolio-selection problem.

2,061 GWActively seeking interconnection at the end of 2025: 1,312 GW of generation plus 749 GW of storage (Measured).
549 GWQueued capacity with a draft or executed interconnection agreement but not yet operating (Measured).
13%Share of 2000–2020 requested capacity that had reached operation by the end of 2025; 75% withdrawn (Measured).

Time is the price this market charges. Among projects that reached operation, the median request-to-operation span ran about 22 months for the 2008 cohort, 36 months for 2015, and 61 months for projects completed in 2025 (Measured, Berkeley Lab)—nearly a tripling across three cohorts. The stages split similarly: about 45 months from request to interconnection agreement, then a median 31 months from agreement to operation in 2025, against 21 months in 2008 (Measured).

Throughput explains why the queue is shrinking while the clock stays long. Active capacity stood at 2,061 GW at the end of 2025 (1,312 GW generation, 749 GW storage), down 10% year over year and 21% from the 2023 peak of 2,598 GW, as more than 750 GW withdrew during 2025 alone (Measured). The active mix is solar 773 GW, storage 749 GW, gas 253 GW—up 86%—and wind 220 GW (Measured). With 549 GW holding an interconnection agreement but not yet operating, a falling queue mostly records attrition, not faster delivery.

The queue is therefore neither a forecast nor pure noise. It records the option value developers place on network access. Withdrawal can mean a speculative proposal failed; it can also mean upgrade costs, study delays, land, procurement, financing, or power contracts made an otherwise buildable plant uneconomic.

The bottleneck has two clocks

ClockEarlier benchmarkRecent benchmarkWhat it measures
Generator interconnection22 months · projects built 200861 months · projects built 2025Request to commercial operation among projects that finished.
Federal environmental reviewFragmented agency processes~4-year historical average; two-year CITAP targetNotice of intent to record of decision, not the whole project.
New transmissionProject-specific~10 years average in DOE-cited reviewDevelopment through completion across 30-plus projects.
Existing-corridor upgradeStatic operationOften 1–3 years where feasibleGETs or reconductoring without a new right-of-way.
Part III: The cost stack

The wire is only one layer of a transmission line

Steel, aluminium, copper, insulation, concrete, and power electronics are tangible. The route, approvals, system studies, beneficiary agreement, construction windows, and operating rules determine whether those materials become useful infrastructure.

01

Choose a need

Forecast load, retirements, generation, reliability events, and trade across a network whose future is uncertain.

Layer
Planning
Output
Commissioned, operable transfer capability
02

Decide who benefits

A line can lower energy cost, improve reliability, and unlock generation in different places. Agreement over who pays often precedes engineering.

Layer
Cost allocation
Output
Commissioned, operable transfer capability
03

Secure a path

Rights-of-way, state and federal approvals, environmental review, tribal consultation, landowner agreements, and community design define the buildable route.

Layer
Siting
Output
Commissioned, operable transfer capability
04

Build the terminals

Substations, breakers, transformers, converter stations, protection, and controls determine whether conductor capacity can enter the operating grid.

Layer
Equipment
Output
Commissioned, operable transfer capability
05

String and commission

Towers, foundations, conductors, access roads, specialist labour, outages, testing, and market integration finally create usable transfer capability.

Layer
Construction
Output
Commissioned, operable transfer capability

The physical floor is lower than the delivered project

Ohmic loss is unavoidable: current heats a conductor in proportion to current squared and resistance. Higher voltage moves the same power with less current, which is why long-distance systems climb from distribution voltages to hundreds of kilovolts and why HVDC becomes attractive for particular long, controlled transfers.

But today's dominant gap is rarely between conductor performance and a thermodynamic limit. It is between a viable electrical design and a commissioned asset. The materials set a floor; coordination sets much of the premium and the variance.

Part IV: The option in the ground

An existing corridor is a platform

Once a route has towers, access, easements, known neighbours, and a place in operating models, its reuse can avoid the slowest parts of a greenfield project.

Dynamic line ratings measure weather and conductor conditions instead of assuming a conservative fixed limit. Power-flow controls redirect electricity around overloaded elements. Topology optimization finds better network configurations. Advanced conductors can tolerate higher temperatures with less sag and, on suitable structures, roughly double capacity.

These are not four versions of free capacity. A windy-day rating is variable. A rerouted flow consumes headroom elsewhere. A stronger conductor may expose a substation limit. Reconductoring requires outages and structures that can accept the design. Their value is speed: they buy time and transfer while the system decides where genuinely new corridors are unavoidable.

Upgrade before expansion—but do not confuse them

Operate

Measure and route

Reveal thermal headroom and use the network's spare paths more deliberately.

Fastest · variable or topology-dependent gain
Rebuild

Reconduct and uprate

Reuse a permitted route while replacing wires and, where needed, terminal equipment.

Medium term · potentially near-2× line capacity
Expand

Add new corridors

Create firm geographic transfer that optimization and existing rights-of-way cannot supply.

Slowest · largest structural network change
Part V: Institutions are equipment

A regional plan is part of the machine

Transmission creates multiple products over decades: energy savings, reliability, resource adequacy, resilience, reduced losses, access to generation, and insurance against futures that never arrive exactly as forecast.

Planning only for the first generator that requests service tends to produce piecemeal upgrades and repeated studies. Planning for a portfolio can identify shared facilities, but immediately raises the political question: which future benefits count, and which customers should fund them?

FERC Order No. 1920 requires long-term regional transmission planning and consideration of a broader set of benefits. Order No. 2023 moved generator interconnection toward first-ready, first-served cluster studies. Rules can shorten duplicated work, but they cannot manufacture transformers, settle every state dispute, or create local consent. Reform succeeds when measured in energized capacity and lower congestion—not filings completed.

Planning is sequential

The business case, regional plan, beneficiary analysis, route, permits, equipment orders, and construction cannot all begin at once. Delay at one layer idles the rest.

The cheapest line can be unbuildable

A direct path may cross too many jurisdictions or sensitive landscapes. Route changes raise length and cost before material is purchased.

A line is a network intervention

Its value depends on generation, load, neighbouring constraints, dispatch, and contingencies. Dollars per mile alone cannot describe the useful output.

Transformers can become the clock

A conductor upgrade that outruns terminal equipment simply moves congestion into substations, breakers, and protection systems.

Queues contain options, not forecasts

Developers submit projects under uncertainty and most historical queued capacity has not reached operation. Queue volume measures demand for access, not future supply.

Local costs and broad benefits diverge

Communities host towers and land impacts while reliability and market savings spread across regions. Durable consent needs a distributional answer, not only a net-benefit model.

An optimistic view, with conditions

The grid has a faster lane and a durable lane

Measure, control, and reconductor existing lines now; plan new regional corridors before each individual project proves the need again. The technologies are complementary because one buys years and the other buys geography.

Now

Expose headroom

Deploy ratings, controls, topology tools, storage, and queue reform where they can release capacity without new land.

Next build cycle

Reuse corridors

Reconduct suitable routes and upgrade the substations and protection systems that would otherwise become the next bottleneck.

Durable network

Plan across futures

Build high-capacity regional and interregional paths whose reliability and market value survive any single generator proposal.

Sources, method, and boundaries

This report treats queue entries as applications, nameplate uplift as conditional engineering potential, and targets as targets. It does not collapse overhead lines, underground cables, HVAC, HVDC, interconnection upgrades, or bulk regional facilities into one misleading cost curve.