Bitcoin mining has historically been linked to high energy use and environmental concerns. However, some companies are changing this image by using renewable energy, practicing transparency, and following strong governance principles. These miners show that it is possible to grow profits while reducing environmental impact.
Before we get to know the top sustainable bitcoin mining companies to put on your radar, let’s learn why sustainability is crucial in this space.
Why Greener Mining Matters: Bitcoin’s ESG Future
Bitcoin’s method of securing its network uses a lot of electricity. This has drawn criticism because most mining still depends on fossil fuels. And thus, sustainable miners are working to separate Bitcoin growth from carbon emissions.
As governments and investors seek cleaner energy, companies using renewables can gain. They will enjoy better market access and face fewer regulatory issues.
Sustainable mining also helps communities and local power grids. Some miners locate near renewable power sources where they can take advantage of excess energy and even support grid stability. Clear operations lower environmental and noise issues. This helps build strong ties with local residents.
Moreover, renewable energy often lowers costs, sometimes to less than one or two cents per kilowatt-hour. This reduces the cost to mine each Bitcoin and protects miners from fossil fuel price swings. Since Bitcoin rewards decrease over time, miners with cheap power will stay profitable longer.
In a crowded marketplace, miners that demonstrate a commitment to clean energy can stand out. Certifications and carbon offsets boost their reputation. They also attract investors looking for responsible, future-proof miners. Speaking of, here are the top five bitcoin mining companies showcasing their sustainable, greener operations.
1. Gryphon Digital Mining: Carbon-Negative Mining Using Hydroelectric and Flare Gas Power
Gryphon Digital Mining is among the first publicly traded Bitcoin miners focused on being carbon-neutral, and now carbon-negative. In 2023, over 98% of its electricity came from renewable sources, mainly hydroelectric power, reaching 100% early in 2024. This was confirmed through independent audits.
The company got a sustainable Bitcoin certification, showing its dedication to clear environmental goals. Gryphon regularly publishes its full emissions data, providing transparency for investors. It also links executive pay to sustainability achievements, ensuring accountability.
Gryphon’s mining fleet works efficiently and uses about 28.6 joules for each terahash. This setup produces nearly one exahash of computational power every second. In 2024, it produced Bitcoin valued at millions of dollars monthly, maintaining high uptime and low power costs. The acquisition of flare gas-powered mining assets increased capacity. It costs about one cent per kilowatt-hour.
Gryphon projects a pipeline of 500 megawatts in new clean energy projects, including flare gas sites. It recently bought a large industrial property in Alberta to expand. With new leaders, the company plans to hit several exahashes per second soon. They will focus on using sustainable energy sources.
ESG, Growth, and Strategy
- In 2023, GP4BTC received sustainable Bitcoin certification from Energy Web. This was part of a new effort to standardize energy measurement in mining.
- Plans a 500 MW pipeline of low-cost power projects. This includes flare gas acquisition in Louisiana. It adds 59 PH/s right away at about 1¢/kWh.
- Recently bought an 850-acre industrial site in Alberta for future growth. This move comes under their new CEO, Steve Gutterman. He previously grew TRADE Financial from $1B to $35B in assets.
- Planning to expand hash rate toward multiple EH/s by mid‑2020s, supported by clean power sourcing and carbon-negative posture.
2. CleanSpark: Multi-Source Renewable Energy and Community-Focused Mining
CleanSpark shifted from energy services to Bitcoin mining with a strong environmental commitment. Its mining data centers are in New York, Georgia, and Mississippi. They get about 94% of their power from carbon-free sources like nuclear, hydro, wind, and solar.
One key partnership is with Coinmint, which operates a large hydro-powered facility in New York. This site reports nearly full uptime and plans to reach 100% renewable power. CleanSpark also emphasizes immersion cooling technology, which extends equipment life by reducing heat and energy use. This reduces electronic waste and lowers overall power demand.
The company talks to local leaders before building new facilities. This way, they can address concerns and show benefits, which helps gain social acceptance.
CleanSpark aims to boost its mining capacity from one exahash per second to two. The company is focused on using clean power for this growth.
The company has deep roots in the energy industry since 1987. This experience helps them manage power costs and join grid programs that reward flexibility in demand. It aims for net-zero emissions of direct and indirect operations by 2027.
Targets, Expansion, and Positioning
- CleanSpark has energy infrastructure from 1987. This gives it an edge in negotiating demand-response and grid service programs.
- Through ATL Data Centers and Coinmint, CleanSpark exceeded 470 PH/s earlier in 2022, mining 3,768 BTC (over time) and averaging ~4 BTC/day at peak.
- It aims for net-zero Scope 1 and 2 emissions by 2027. Also, it plans to increase capacity from about 1 EH/s to 2 EH/s and more. The focus will be on keeping a high clean energy share.
3. TeraWulf: Mining Powered by Nuclear and Hydroelectric Energy at Low Cost
TeraWulf runs two major Bitcoin mining sites in the United States. The Lake Mariner facility in New York mostly uses electricity from hydro and nuclear sources. This means it provides about 91% zero-carbon power. The company owns this big operation that has about 110 megawatts of capacity. Plus, it offers over 3.6 exahashes per second of computing power.
The Nautilus Cryptomine site in Pennsylvania uses nuclear power from the Susquehanna plant. It is partly owned and run with partners. This setup cuts electrical costs to about two cents per kilowatt-hour. This boosts profitability.
After selling its stake in the Nautilus project, TeraWulf reinvested capital into expanding Lake Mariner. The company plans to reach approximately 238 megawatts of total capacity by late 2024. It favors the most energy-efficient mining hardware and aims for 100% clean energy powering its operations.
Performance Metrics and Strategic Growth
- By mid-2023, TeraWulf had scaled to around 5.5 exahashes per second and 160 megawatts of mining capacity. It maintained a low cost per Bitcoin mined, well below industry averages.
- In Q2 2024, the company raised its capacity to around 10 exahashes per second. This change led to a 130% year-over-year revenue boost.
- TeraWulf plans to keep using the best mining hardware, like the Bitmain S19 XP Pro and S19 j Pro, which have around 21.5–29.5 J/TH efficiency. They also aim to expand their zero-carbon power sourcing to 100%.
4. Iris Energy: Scaling 100% Renewable Bitcoin Mining and AI Compute Ventures
Based in Australia, Iris Energy, now known as IREN operates mining sites in Canada, Texas, and Australia. Its energy mix is mostly hydroelectric power. It also includes wind, solar, and renewable energy certificates. This adds up to around 97% renewable power.
Iris Energy locates modular mining facilities in regions with a surplus of clean energy. These sites turn extra renewable electricity into Bitcoin. This helps balance local grids and supports communities.
The company owns its land, data centers, and grid connections. This gives it full control over energy use and mining efficiency.
Although it posted modest losses in fiscal 2025, forecasts predict positive earnings in the near future. Institutional investors show interest, partly due to the company’s clean energy commitment.
Iris also develops AI computing services powered entirely by renewable energy. These high-performance GPU clusters provide additional revenue streams alongside Bitcoin mining.
Metrics, Market Position, and Growth
- The stock is attracting strong institutional interest with an A+/A‑ ratings from IBD and a top relative strength score of 98.
- By mid-2025, Iris Energy operated at an estimated 50 exahashes per second and reported strong sales growth (172%).
- Iris offers AI-driven cloud services, powered by renewable-energy-fed GPU clusters (e.g. NVIDIA H100). This adds a higher-margin revenue layer atop its Bitcoin business.
- The company aims to reach 20 exahashes per second by 2026. It is also looking into green hydrogen and more renewable energy projects.
5. Bitfarms: Hydroelectric Mining with Expanded High-Performance Computing
Bitfarms operates mining facilities in Québec, Washington State, Argentina, and Paraguay. These sites primarily use hydroelectric energy, allowing for 95 to 99% renewable power consumption.
The company has a complete environmental, health, and safety management system. Its board oversees this system. It has teamed up with recycling groups to handle electronic waste properly. This effort creates verified carbon credits.
In 2023, Bitfarms operated approximately 5 exahashes per second in Argentina and aimed to increase to around 6 exahashes. The company has shifted part of its focus to U.S. sites, which offer favorable energy prices and market conditions. Bitfarms also invests in high-performance computing and AI infrastructure.
However, not all developments have been smooth. In Paraguay, a mining facility created loud noise pollution. This bothered local residents and led to legal complaints. It still relied on extra hydroelectric power. Bitfarms has since taken steps to resolve these issues. This case highlights the need for miners to manage community impacts carefully.
The company has restructured its operations into divisions. One focuses on traditional mining, and the other covers broader computing services.
Performance, Social Dimensions, and Future Roadmap
- By Jan 2025, the operating hash rate reached ~12.8 EH/s, with a strategic shift toward U.S. facilities to leverage favorable power and market access.
- Total energy portfolio exceeded 950 MW, with flexibility across Bitcoin mining and HPC/AI operations.
- Developing a 120 MW high-performance computing and AI site in Sharon, Pennsylvania, within the PJM grid—seeking to monetize infrastructure across both mining and HPC sectors.
Clean Hashes, Clear Conscience: A New Era in Bitcoin Mining
The five companies profiled here—Gryphon Digital Mining, CleanSpark, TeraWulf, Iris Energy, and Bitfarms—illustrate the evolving landscape of sustainable Bitcoin mining. Each company combines renewable power, transparency, and strategic growth with a commitment to environmental responsibility.
Gryphon leads with carbon-negative mining and flare gas utilization. CleanSpark emphasizes multi-source renewables and community engagement. TeraWulf focuses on nuclear and hydro to minimize costs.
Meanwhile, Iris Energy specializes in modular, 100% renewable operations and diversifies into AI computing. And Bitfarms leverages hydroelectric sites and expands into high-performance computing while managing community challenges.
Overall, sustainable bitcoin mining is becoming essential. With rising energy scrutiny, investor demand for climate alignment, and stricter regulations, these firms offer scalable models that align economic growth with ecological responsibility.
