The cheapest hosting rates in North America are not the result of a better negotiation with a utility. They come from a facility that is willing to stop mining on command. Understanding curtailment is understanding where your rate comes from — and what it costs you.

Mining as a flexible load

Grid operators have a permanent problem: supply and demand must match every second, and demand is unpredictable while generation is increasingly variable. Their traditional tools — spinning up peaker plants, importing power at spot prices — are expensive and slow.

A bitcoin mine is the most cooperative large load on the grid. It can drop from 30 MW to near zero in under a minute, with no product spoiled, no process ruined, no shift sent home. That flexibility has a market value, and operators are paid for it.

Three ways a facility gets paid to stop

Economic curtailment

When the wholesale price of power rises above the value of the bitcoin the machines would mine, the facility sells its power position back into the market instead of hashing. During ERCOT summer peaks, spot prices can exceed $1,000/MWh — hours where not mining is worth many multiples of mining.

Ancillary services

The facility commits to responding to grid frequency events within seconds and is paid a standing fee for that commitment, whether or not it is ever called. This is steady revenue, not opportunistic, and it is the least visible of the three to the client.

Demand response programs

Utility-run programs pay large loads to reduce consumption during declared peak events — typically a limited number of hours per year, announced in advance. Compensation is a mix of capacity payments and per-event energy credits.

How this reaches your invoice

Facilities pass this value through in three broad models. Knowing which one you are signing is essential:

• Blended fixed rate. The provider absorbs curtailment revenue and risk, and quotes you one low number for the term. Predictable; the provider keeps the upside.
• Pass-through with credits. You pay an index-linked rate and receive curtailment credits on your invoice. Lower average cost, higher month-to-month variance.
• Revenue share. Curtailment proceeds are split by an agreed formula. Most attractive at scale, most demanding on reporting quality.

The cost side: uptime you do not get

Every curtailed hour is an hour your machines do not hash. In a heavy curtailment market that can be 3–8% of annual runtime, concentrated in a few summer weeks. The arithmetic is straightforward but frequently ignored:

If curtailment credits and rate savings exceed the mining revenue lost during those hours, curtailment is profitable for you. If they do not, the low headline rate is being funded out of your hashrate.

This is why the contract language in our provider selection guide matters so much: curtailed hours must be excluded from the uptime guarantee and unbilled for energy. Anything else and you are paying twice.

What to ask a facility about curtailment

• Which market and programs is the site enrolled in, and under what contract structure?
• How many curtailment hours did the site actually see in each of the last three years?
• Is curtailment economic (price-driven) or reliability-driven, and who makes the call?
• How is curtailment reported to clients — per-event timestamps, or a monthly total?
• How are credits calculated, and where do they appear on the invoice?

A facility that can answer with three years of hour-level history is running a real energy desk. One that answers “rarely, only in emergencies” either is not enrolled in anything — in which case ask why its rate is still high — or is not measuring.

Where this is heading

Grid interconnection queues in the United States are years long, and new flexible load is one of the few things a utility can approve quickly. That structural advantage is why mining hosting keeps migrating toward stranded gas, curtailed wind, and behind-the-meter generation. For a hosting client, the practical takeaway is simple: the rate is only half the contract. The other half is what happens in the hours you are not allowed to mine.