On Feb. 20, Brazil’s foreign trade council published a technical resolution reducing import duties to zero for a narrow class of hardware: SHA256 Bitcoin miners exceeding 200 terahashes per second with energy efficiency below 20 joules per terahash.
Three days later, French state-owned energy giant Engie told Reuters it was considering installing Bitcoin miners at its 895-megawatt Assu Sol plant in northeast Brazil, the company’s largest solar facility globally, to monetize curtailed electricity and improve profitability.
The two developments landed within 72 hours of each other, and together they sketch a thesis most observers missed: Brazil is building a pressure valve for stranded renewable energy, and Bitcoin mining is the release mechanism.
This isn’t a story about Brazil “legalizing” mining or launching a national strategy. It’s about the quiet convergence of three forces: chronic curtailment, falling hardware cost barriers, and generator economics breaking.
Together, they create the conditions for incremental hashrate to flow toward a market nobody was watching.
The curtailment problem that Bitcoin miners can solve
Brazil’s wind industry curtailed roughly 32 terawatt-hours between October 2021 and September 2025, amounting to about 6 billion reais (roughly $1.2 billion) in lost revenue for wind farms.
Curtailment occurs when the grid can’t absorb the electricity being produced due to the wrong place, the wrong time, or insufficient transmission capacity. For renewable generators, curtailed megawatt-hours are destroyed value.
Wind and solar generated 24% of Brazil’s electricity in 2024, and in August 2025, that share hit 34% for the first time.
Grid operator ONS describes curtailment as a structural feature of systems with high shares of variable renewables, not a temporary friction.
As the renewables mix rises and transmission buildout lags, the mismatch grows. Generators need local, dispatchable demand that can absorb otherwise-wasted electrons and turn on or off quickly. Bitcoin mining fits that profile precisely.
Engie’s Assu Sol plant is located in Brazil’s northeast, a region with strong solar irradiance but transmission constraints.
The company told Reuters that mining or storage could make the facility more profitable by monetizing energy that would otherwise be curtailed, but emphasized this would take years to implement.
The signal matters because it’s coming from a state-owned European utility with no prior crypto exposure, framing mining purely as an industrial demand response tool.
What the tax change actually does to Bitcoin miners
Resolução GECEX 861, published Feb. 20, amends Brazil’s consolidated ex-tariff list to reduce import duty to zero for specific information technology goods.
Annex I adds a new line covering servers dedicated to cryptocurrency mining using the SHA256 algorithm with energy efficiency measured at 35 degrees Celsius, below 20 joules per terahash, and processing capacity above 200 terahashes per second.
The zero-percent duty remains in effect through Jan. 31, 2028.
This is not a blanket exemption for all mining hardware. The thresholds filter for top-tier ASICs. Older or less efficient models don’t qualify. The policy targets the hardware class that can actually compete at scale in a professional mining environment.
Brazil’s import tax structure is notoriously layered. Import duty is one component of the total landed cost, along with IPI, PIS/COFINS-Import, ICMS, and various fees. Trade logistics guides commonly cite total import burdens in the 40%-100% range.
Cutting import duty to zero removes one federal lever but doesn’t eliminate the full stack.
Nevertheless, Brazil reduced a key cost barrier for high-efficiency mining hardware, lowering payback periods, even though other taxes remain.
The break-even power price that makes this work
Mining profitability depends on three variables: hash price (revenue per terahash per second per day), hardware efficiency, and electricity cost.
As of Feb. 16, Hashrate Index reported a hash price of around $34.05 per petahash per second per day. Bitcoin traded near $64,000 on Feb. 23.
For a minimum-qualifying rig under Ex 040, with 200 terahashes per second at 20 joules per terahash, daily revenue equals roughly $6.81. Power consumption is 4.0 kilowatts. Daily energy use is 96 kilowatt-hours.
The break-even electricity price, ignoring capital expenditure and operating overhead, is about $0.071 per kilowatt-hour.
Converting to reais using the Feb. 23 exchange rate of roughly 5.17 reais per dollar, break-even sits around 370 reais per megawatt-hour. Retail business electricity prices in Brazil averaged 0.657 reais per kilowatt-hour in June 2025, which is far too high for mining.
However, wholesale spot prices often trade in the 250-450 reais per megawatt-hour range, and curtailed energy, by definition, has no better buyer.
If a generator can sell otherwise-lost megawatt-hours to a miner at or below its break-even cost, the generator recovers revenue that would otherwise be zero.
This is the mechanism: curtailment creates stranded value, mining converts stranded value into computation, and the ex-tariff drops hardware cost enough to tighten the arbitrage window.
What happens if the thesis plays out
If Brazil’s curtailment persists or grows, driven by continued renewables buildout outpacing transmission capacity, generators will face mounting revenue pressure.
Mining offers a bilateral PPA structure that requires no new transmission and can ramp within days of hardware delivery. The ex-tariff remains in effect through January 2028, creating a 24-month window for miners to lock in hardware cost certainty while testing curtailment economics.
Engie’s pilot framing suggests other utilities and independent power producers will evaluate similar options. If several large renewable projects announce colocation deals over the next 12 months, Brazil becomes a meaningful incremental hashrate destination.
This happens not because of national strategy, but because project-level economics align.
The country already has regulatory clarity around Bitcoin, established banking infrastructure for crypto firms, and no capital controls that would trap mining revenue onshore.
Yet, the thesis can also fail. If transmission upgrades accelerate and reduce curtailment, the stranded energy pool shrinks, and power prices rise.
If Bitcoin’s difficulty spikes, compressing the hash rate below the $30-per-petahash range, break-even power costs drop below what most curtailment contracts can deliver.
If local permitting or grid interconnection processes create friction for data center builds, the hardware cost advantage becomes irrelevant.
And if the ex-tariff expires in January 2028 without renewal, the import cost barrier returns.
| Bucket | Metric | Value | Why it matters |
|---|---|---|---|
| Curtailment scale | Wind curtailment (Oct 2021–Sep 2025) | 32 TWh | Defines the “stranded value” pool mining targets |
| Curtailment impact | Wind revenue lost (same period) | R$6B (~$1.2B) | Shows curtailment is an economics problem, not a rounding error |
| Renewables penetration | Wind+solar share of generation (2024) | 24% | Higher VRE share tends to raise congestion/curtailment pressure |
| Renewables penetration | Wind+solar share (Aug 2025) | 34% | “First time” milestone that signals structural shift |
| Policy filter | Eligible hardware | SHA256, >200 TH/s, | Targets top-tier ASIC class; excludes older rigs |
| Policy window | 0% import duty valid through | Jan 31, 2028 | Time-bounded “option window” for miners to move |
| Utility signal | Engie Assu Sol plant size | 895 MWp | Big enough to matter; shows serious generator interest |
| Mining revenue | Hashprice (Feb 16) | $34.05 / PH/s/day | Anchors profitability math |
| Rig economics | Min qualifying rig daily revenue | ~$6.81/day | Ties revenue to a specific machine class |
| Rig economics | Power draw | 4.0 kW | Converts efficiency → electricity cost sensitivity |
| Rig economics | Daily energy | 96 kWh/day | Makes break-even intuitive |
| Break-even power | Electricity break-even | $0.071/kWh (~R$370/MWh) | The number that decides “hub or not” |
| Price reality check | Retail business electricity (June 2025) | R$0.657/kWh (R$657/MWh) | Shows why miners need wholesale/curtailment pricing |
| Price reality check | Wholesale spot band (often) | R$250–450/MWh | Shows feasibility zone exists sometimes |
The Bitcoin miner constraint no one talks about
Zero-percent import duty matters, but it doesn’t fix the financing gap.
Mining hardware has a useful life measured in difficulty epochs, not decades. Brazil’s cost of capital is higher than in the US or Europe, and local banks have limited appetite for crypto-native credit.
Miners scaling in Brazil will need either offshore financing denominated in dollars or equity structures that can absorb illiquidity.
The other constraint is operational. Mining at renewable plants works when curtailment is predictable or when contract structures allow interruptible load.
However, if curtailment becomes sporadic or grid dynamics shift hour to hour, uptime suffers, and effective hash price declines.
Engie’s “years to implement” comment suggests the company understands that bolt-on mining infrastructure requires engineering, not just a PPA signature.
What Brazil is actually betting on
Brazil didn’t wake up and decide to become a mining hub. It created a targeted cost reduction for hardware that can monetize a structural grid problem, and a state-owned utility publicly tested the narrative on the same day.
The bet is narrower than it looks: can miners absorb enough curtailed energy to improve generator economics without destabilizing the grid or creating new political risk?
If the answer is yes, Brazil captures incremental hashrate without subsidizing it directly: miners pay for power, generators recover lost revenue, and the ex-tariff removes friction.
If the answer is no, the resolution expires in January 2028, and the experiment ends. Either way, the policy is time-bound, the economics are transparent, and the commitment is reversible.
But options have value when the underlying conditions align, and Brazil’s conditions are aligning.
Curtailment is growing, hardware costs just dropped, and a major generator is publicly pricing the trade-off.
The window is open through January 2028. What happens next depends on whether enough miners recognize the opening before it closes.