Resources · Updated June 2026

What Is
Curtailment?

In everyday use, to curtail something is to cut it back. In electricity, curtailment is the deliberate reduction of power generation or consumption when the grid can't use, transmit, or afford the energy available at that moment.

9 min read · Grid fundamentals

One of the Grid's Largest Sources of Waste

Plain English vs. the energy meaning

Curtailment means something simple in plain English and something very specific in energy. The energy version has become one of the largest sources of waste on the modern grid.

This guide covers what "curtail" means, what curtailment means in electricity, the main types, why it happens, why it's a growing problem, and how it's being turned into a paid grid resource.

What Does "Curtail" Mean?

Reduce, cut short, restrict

To curtail means to reduce, cut short, or restrict something. "Curtailed" describes something that's been reduced. "Curtailing" is the act of cutting it back. The word applies to budgets, rights, or schedules just as easily as to power. In energy, it takes on a precise operational meaning.

Curtailment in Electricity

Deliberate, not a blackout

In electricity, curtailment is the intentional reduction of power output or consumption, ordered when the grid is out of balance: too much supply, not enough transmission capacity, or prices that have fallen below zero.

It's deliberate and controlled, which is what separates it from a blackout (an uncontrolled loss of power) and from an outage (an equipment failure). Curtailment is a tool grid operators use on purpose to keep the system stable.

Types of Curtailment

Wind, solar, generation, load

Wind curtailment
The deliberate reduction of available wind generation when the grid can't absorb or move it, wasting clean energy that has no buyer in that interval. It's now the most common form of energy curtailment in wind-heavy regions. SPP curtailed an average of 1,097 MW of wind every hour in 2023, eight times the 136 MW of 2019 (SPP Market Monitoring Unit).
Solar curtailment
The same reduction applied to solar output, most often in the middle of the day when solar floods the grid faster than demand can use it — the trough of the "duck curve."
Generation curtailment
The general term for cutting any generator's output, renewable or conventional, when the system can't accept it.
Load curtailment
Curtailment seen from the demand side: reducing a facility's electricity consumption rather than a generator's output. Load curtailment is the form that can be paid — a load that agrees to cut consumption on command becomes a grid resource, the basis of demand response.

Why Curtailment Happens

Three conditions drive it

Oversupply
Renewables produce more than demand needs, so output has to be cut to keep the grid balanced.
Transmission limits
The lines that would carry the power are full, stranding generation behind the bottleneck.
Negative prices
When supply is overwhelming, wholesale prices fall below zero and generators are effectively paid to stop. In SPP, negative-price intervals reached 15.2% of the real-time market in 2024 — a direct signal of surplus with nowhere to go.

Why Curtailment Is a Problem

A symptom of a flexibility gap

Every curtailed megawatt-hour is energy that was generated, or could have been, and then thrown away. The costs compound: wasted clean power, weaker returns on the wind and solar farms built to produce it, distorted prices, and emissions from backup generation that flexible demand could have avoided.

Above all, curtailment is a symptom of a flexibility gap. The grid has energy with no buyer at the moment it's cheapest.

Turning Curtailment Into a Resource

Flexible demand, proven economics

More transmission helps, but the durable fix is flexible demand: load that consumes surplus when it appears and curtails on command when the grid is tight. A flexible load placed next to stranded wind absorbs power that would otherwise be curtailed, behaving like a battery that charges on excess energy. That function is called virtual energy storage.

On the demand side, load curtailment becomes a paid service. Grid operators compensate loads that reduce consumption during stress, which is what demand response delivers.

In ERCOT, Riot Platforms, a Bitcoin miner operating a fully interruptible compute load, reported $71.2 million in power curtailment credits across 2023 — earned by absorbing surplus power and curtailing on demand.

That's curtailment turned from pure waste into a grid asset, and scaling it is the work Type 3 exists to do.

End Curtailment. Enable Every Megawatt.

Type 3 is the software-defined demand response infrastructure company that turns fully interruptible compute loads into a dispatchable, telemetry-verified grid resource. Read the Manifest →

Curtailment Credits

Getting paid to curtail

A curtailment credit is a payment a resource earns for reducing its load during a grid event or a high-price interval. In practice, a registered interruptible load earns two streams: a standing payment for being available to curtail, and a performance credit each time it's actually dispatched.

For a large, fully interruptible load, those power curtailment credits can run into the tens of millions of dollars a year, turning the grid's surplus problem into the load's revenue.

Curtailment FAQ

What does curtail mean?
To curtail means to reduce, cut short, or restrict something. In electricity, to curtail is to deliberately lower power generation or consumption when the grid can't use or move the available energy.
What is curtailment in simple terms?
Curtailment is when the grid deliberately cuts back electricity, either by reducing how much a power plant generates or how much a large facility consumes, because there's too much supply, not enough transmission, or prices have gone negative. It's a controlled, on-purpose action, not a blackout.
What is wind curtailment?
Wind curtailment is the deliberate reduction of available wind power when the grid can't absorb or transmit it, wasting clean energy with no buyer at that moment. SPP curtailed an average of 1,097 MW of wind per hour in 2023, eight times its 2019 level.
Why is renewable energy curtailed?
Renewable energy is curtailed mainly because of oversupply, transmission bottlenecks, and negative prices. Wind and solar often generate the most when demand is low or local lines are full, so the grid cuts their output to stay balanced. A co-located flexible load could consume that energy instead.
How much do you get paid to curtail electricity?
Payment varies by market and by how much load you can reliably shed, and usually combines a standing availability payment with a performance credit per dispatch. As a benchmark, Riot Platforms reported $71.2 million in ERCOT power curtailment credits in 2023 for operating a large fully interruptible load.
What is the difference between curtailment and demand response?
Curtailment is the act of reducing power output or consumption. Demand response is the paid, organized practice of having loads curtail on the grid's signal. Load curtailment is the action; demand response is the market program that compensates it.

Related Terms

See the full glossary in the Manifest

Curtailment
The deliberate reduction of electricity output or consumption when the grid cannot absorb, transmit, or afford the available power.
Energy curtailment
The umbrella term for reducing generation or consumption, on either the supply or demand side, when the grid can't use the power available.
Wind curtailment
The deliberate reduction of available wind generation when the grid cannot absorb or transmit it. SPP curtailed an average of 1,097 MW of wind every hour in 2023 — eight times the 2019 level — surplus a co-located flexible load could consume.
Load curtailment
The reduction of an electricity load's consumption, on command or by agreement, to relieve stress on the grid — demand response seen from the load's side.
When the grid has so much supply that generators pay to keep producing rather than shut down, pushing prices below zero. A flexible load consuming during these intervals is paid to absorb energy that would otherwise be wasted.
A condition where generation, often renewable, exceeds what the grid can use or transmit at that moment, forcing curtailment to keep supply and demand balanced.
Using flexible loads to mimic a battery: absorbing surplus power when energy is abundant, freeing capacity by curtailing when it is scarce — without the capital cost, chemical degradation, or state-of-charge limit of a physical battery.
A payment a resource earns for reducing its load during a grid event or high-price interval. For large interruptible loads in ERCOT, these can run into the tens of millions of dollars a year.
The practice of changing electricity consumption in response to grid conditions or prices, so demand flexes to match supply. Type 3 delivers deterministic demand response — 100% interruptible, on command, not probabilistic.
Flexible load
An electricity load that can raise, lower, or shift its consumption in response to grid signals. Type 3's fully interruptible compute load is the most extreme form: one that can drop to zero on command.

Sources & References

  • Southwest Power Pool — Annual State of the Market reports, Market Monitoring Unit (2023–2024).
  • Riot Platforms, Inc. — power-credit disclosures (SEC filings, 2023).
  • ERCOT — Controllable Load Resource program documentation (2024–2025).