CleanSpark Leads as Heatwave Slows Rival Miners

Bitcoin Mining Update June 2025: CleanSpark Surges While Riot, Cipher, and Marathon Cut Output Amid Texas Heatwave

Bitcoin Miners Face Heatwave Pressures – But CleanSpark Powers Ahead

In June 2025, the Bitcoin (BTC) mining landscape saw a notable divergence in strategy and outcomes. While several major mining firms—Riot Platforms, Cipher Mining, and Marathon Digital Holdings (MARA)—reduced operations due to high summer electricity demand and cost-saving strategies, CleanSpark defied the trend, posting impressive growth in both production and hashrate.

This contrast in performance underscores a shifting competitive dynamic in the Bitcoin mining industry, driven by energy market pressures, strategic decisions, and operational agility.

Riot Platforms: Strategic Curtailments Lead to Output Dip

Riot Platforms, one of the leading U.S.-based Bitcoin miners, reported a 12% decline in BTC production in June 2025. The company mined 450 BTC, down from 514 BTC in May. The reduction was attributed to “economic curtailment”—a voluntary decision to scale back mining operations during periods of high electricity demand in Texas.

According to CEO Jason Les, Riot's participation in the ERCOT Four Coincident Peak (4CP) program plays a critical role in balancing grid stability and cost control.

“Our proactive curtailment strategy significantly contributes to grid stability while enhancing Riot’s competitive positioning,” Les stated.

By reducing its electricity usage during peak hours, Riot benefits from lower power costs throughout the year, a tradeoff that temporarily impacts mining output but improves long-term efficiency.

Key Figures:

BTC mined: 450
BTC sold: 397 (for $41.7 million)
BTC holdings (end of June): 19,273

This tactical move reflects a broader shift among miners toward grid-conscious operations, especially during energy-intensive summer months in states like Texas.

Cipher Mining: Power Cost Efficiency Over Production Volume

Cipher Mining, another major U.S. Bitcoin mining firm, also saw a slowdown, reporting 160 BTC mined in June—a significant reduction from previous months. The company cited its “proactive 4CP avoidance strategy” as the main factor behind its lower output.

Cipher’s goal was to sidestep the expensive 4CP penalties in Texas by cutting power usage during key demand intervals. Despite the reduced output, the firm emphasized that the decision preserved its position as one of the lowest-cost power users in the mining industry.

“Avoiding costly 4CP penalties keeps Cipher highly competitive on energy expenses,” the company noted.

In late June, Cipher’s new Black Pearl site began contributing to overall hashpower, but the site’s impact wasn't yet enough to counteract the broader decline.

Key Figures:

BTC mined: 160
BTC sold: 58
BTC holdings (end of June): 1,063

Cipher’s strategy emphasizes sustainability over short-term gains, prioritizing cost management and network resilience amid volatile energy conditions.

Marathon Digital Holdings: 25% Production Drop

Marathon Digital Holdings (MARA) joined Riot and Cipher in curtailing operations, citing weather-driven constraints and equipment-related factors as key reasons behind a steep 25% drop in Bitcoin production.

In June, Marathon mined 211 BTC, down from 282 BTC in May. CEO Fred Thiel attributed the decline to:

Strategic energy curtailments
Use of older-generation mining hardware
Natural variability in block luck, particularly within the company's proprietary mining pool

“This is an expected dynamic when operating our own mining pool,” Thiel said, acknowledging the probabilistic nature of Bitcoin mining.

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Marathon’s approach reflects a cautious stance in an environment of rising power costs and aging infrastructure. While the company continues to scale, the challenges of equipment performance and network variance remain real hurdles.

Key Figures:

BTC mined: 211
(No public update on BTC sold or held in this period)

CleanSpark Shines with Record Growth and Rising Hashrate

Amid industry-wide slowdowns, CleanSpark stood out as the lone outlier—boosting its BTC production by 6.7% in June to reach 445 BTC. This growth came at a time when competitors were scaling back, demonstrating CleanSpark’s operational momentum and strategic foresight.

Remarkably, the company sold only 8 BTC, signaling a strong HODL (hold on for dear life) approach to treasury management. With a total reserve of 6,591 BTC, CleanSpark is positioning itself as a long-term player in the evolving Bitcoin ecosystem.

But the most impressive figure is its hashrate milestone: CleanSpark surpassed 20 exahashes per second (EH/s)—more than double its December 2024 output. This makes CleanSpark one of the fastest-scaling miners in North America.

“Surpassing 20 EH/s is a testament to our team’s relentless execution and efficiency,” said CEO Zach Bradford.

The company has its sights set even higher, with active expansion projects in Wyoming and Tennessee expected to push CleanSpark toward its ambitious 50 EH/s target.

Key Figures:

BTC mined: 445
BTC sold: 8
BTC holdings (end of June): 6,591
Operational Hashrate: 20 EH/s (goal: 50 EH/s)

Energy Curtailments: A Growing Trend in Bitcoin Mining

The divergence in miner performance during June 2025 underscores a growing trend: strategic energy curtailment is becoming a standard tool for large-scale Bitcoin miners—particularly in energy-intensive states like Texas.

Programs like ERCOT’s 4CP not only incentivize reduced power usage during critical periods but also reshape how miners evaluate profitability and uptime. This trend favors miners with flexible infrastructure, newer equipment, and access to cheaper power contracts.

However, while this approach supports grid resilience and long-term economics, it presents short-term challenges to consistent Bitcoin output—especially during peak demand seasons.

CleanSpark’s Playbook: A Glimpse at the Future of Mining

What sets CleanSpark apart isn’t just its growth numbers—it’s the strategy behind them. By doubling down on operational expansion and maintaining low BTC sales, the company signals confidence in Bitcoin’s long-term value and its own internal economics.

With a more aggressive investment in high-efficiency hardware, geographic diversification, and a clear roadmap toward 50 EH/s, CleanSpark offers a blueprint for modern mining success.

As older-generation miners and less agile firms struggle with heatwaves, equipment lag, and regulatory shifts, firms like CleanSpark are positioning themselves as next-generation leaders in the digital gold rush.

Conclusion: A Divided Bitcoin Mining Landscape

June 2025 paints a picture of two paths in the Bitcoin mining world:

Conservative Scaling and Curtailment Riot, Cipher, and Marathon are playing the long game by balancing grid responsibilities, controlling costs, and adapting to energy volatility.
Aggressive Expansion and Record Growth CleanSpark, on the other hand, is charging forward—expanding hashrate, increasing production, and building for a future where scale and efficiency are king.

As Bitcoin's price continues to fluctuate and energy markets evolve, the coming months will reveal which strategy proves most resilient—and profitable.