Limenet Issues First Blockchain-Based Carbon Removal Credits via Carbonmark Direct to Scale Its Novel Ocean Alkalinity Enhancement Technology
Carbonmark has issued the first 14.7 ocean alkalinity enhancement credits from Limenet, the Italian climate tech pioneer behind the world’s largest ocean-based CO₂ removal facility. These credits are now live and available for purchase via the Carbonmark platform—marking a major milestone in the Voluntary Carbon Market (VCM) and a leap forward for ocean-based climate innovation.
The credits are transparently recorded on an immutable public blockchain and include integrated dMRV (digital Measurement, Reporting, and Verification) data, ensuring unparalleled auditability. Each onchain credit corresponds to carbon durably stored in the ocean as equilibrated calcium bicarbonates, while also helping reverse ocean acidification and restore marine ecosystems.
Powered by Limenet’s patented pH-equilibrated Ocean Alkalinization technology, the credits represent a scientifically validated, digitally transparent, and verifiably permanent form of CO₂ sequestration.
Technology Serving Nature
Limenet’s facility in Augusta, Sicily—once part of Italy’s “Quadrilatero della morte,” a region devastated by petrochemical pollution—has become a powerful symbol of environmental restoration. Operational since September 2023, the plant currently processes 800 tonnes of CO₂ per year, with plans to scale to 100,000 tonnes annually by 2028.
The process begins with seawater sourced from the Bay of Augusta, whose chemical parameters are first measured. Then, CO₂ sourced from a nearby biogas plant—produced via organic waste fermentation—is introduced. This mixture is combined in a custom reactor with hydrated lime (calcium hydroxide). The result is an aqueous solution of calcium bicarbonate, which, once returned to the ocean, creates a durable and stable carbon sink capable of sequestering CO₂ for over 10,000 years, while simultaneously enhancing ocean alkalinity.
Limenet’s technology is backed by years of scientific research from leading institutions such as Politecnico di Milano and Università Milano-Bicocca. Their research group, Desarc Maresanus, has published over 10 scientific papers validating this approach.
A Breakthrough for the VCM
Traditional carbon registries often take 12 to 18 months to approve novel carbon removal methodologies. In contrast, using Carbonmark’s Direct issuance system, Limenet’s credits were brought to market in just two weeks, following independent verification by RINA.
dMRV (digital Measurement, Reporting, and Verification) enables real-time data collection on the blockchain, allowing buyers, auditors, and regulators to see exactly how, when, and where carbon was removed or reduced—eliminating the need for blind trust and significantly improving accountability. In Limenet’s case, with data sourced directly from sensors, the system minimizes the potential for human error or inaccuracies—building trust among stakeholders.
Unlike most credits issued through conventional systems, Limenet’s are:
Backed by real-time data recorded on the Polygon blockchain for unmatched transparency
Designed for trust, with every tonne tracked from capture to permanent storage
Available for fractionalized retirement, down to 1 kg of CO₂, enabling broader accessibility and participation
A New Standard for Carbon Credit Issuance
Carbonmark and Limenet’s partnership demonstrates what’s possible when technology, science, and digital innovation converge:
Speed: From methodology to market in weeks—not years
Flexibility: Validation accepted from engineering firms, bypassing legacy registry constraints
Transparency: Blockchain-based tracking ensures trust and eliminates double counting
Accessibility: Lower barriers make participation viable for a broader range of project developers working on novel carbon removal methodologies.
Science-based Carbon Offsetting Available to Everyone
The first batch of Limenet carbon removal credits is now available for retirement on Carbonmark’s Marketplace. Companies and individuals looking to offset emissions with high-integrity carbon removal can support one of the most advanced and environmentally impactful projects in the world—at any scale, from tonnes to kilograms.
About Limenet
Limenet is an Italian climate tech startup pioneering carbon removal through its patented pH-equilibrated Ocean Alkalinization technology. By mimicking natural processes, Limenet permanently stores CO₂ in seawater as calcium bicarbonates. In addition to carbon removal, this solution combats ocean acidification and helps restore marine ecosystems—delivering scalable, transparent, and scientifically verified results.
For more information, visit limenet.tech.
About Carbonmark
Carbonmark is an open and fully transparent blockchain-powered marketplace for carbon credits, enabling faster, more flexible, and traceable credit issuance and retirement. Through its Direct credit issuance mechanism, Carbonmark empowers climate innovators like Limenet to bypass traditional registry bottlenecks—bringing high-quality, science-driven carbon credits to market in a fraction of the time. Carbonmark’s infrastructure guarantees public traceability, eliminates double counting, and supports fractionalized retirements—making participation in the VCM accessible for all.
For more information, visit www.carbonmark.com.
