Isometric has certified the Enhanced Weathering in Closed Engineered Systems Module. This module details requirements and procedures for the durable storage of carbon dioxide via Enhanced Weathering (EW) conducted in closed engineered systems.
This follows a comprehensive 30-day public consultation that included feedback from buyers, suppliers, and leading academics with expertise in carbon mineralization and geochemistry. Full details on the evolution of the module and how Isometric addressed feedback from the public consultation are available in the module changelog and public consultation summary.
EW is a carbon dioxide removal (CDR) technology that accelerates the Earth’s natural weathering process. In nature, carbon dioxide dissolved in rainwater reacts with minerals in rocks, forming stable bicarbonate ions. These ions are carried by rivers to the ocean, where the carbon is durably stored for tens of thousands of years. Typically, in EW, this process is accelerated by crushing rocks into a fine powder and applying it to soil—dramatically increasing the surface area of the rocks and enabling them to react more readily with carbon dioxide.
EW can also take place in closed engineered systems, where carbon dioxide removed from the atmosphere through other CDR technologies—such as Direct Air Capture (DAC)—is dissolved in water, mimicking the role of rainwater in natural weathering. This solution then reacts with minerals in an engineered chamber, known as a reactor. As in natural weathering, this produces bicarbonate ions, which can be safely released into river systems or directly into the ocean, where the carbon dioxide is durably stored. This process is also known as engineered EW.
Conducting EW in a closed system enables direct control over key factors that influence the rate of reaction—such as temperature and pressure. It also allows for direct measurement of inputs and outputs from the reactor, providing a high degree of confidence in the amount of carbon stored.
Carbon dioxide removed from the atmosphere through a range of CDR technologies can be used under the Enhanced Weathering in Closed Engineered Systems Module, including DAC, Biogenic Carbon Capture & Storage, and Direct Ocean Capture.
This module takes a scientifically rigorous approach to monitoring, reporting, and verification. It includes procedures and requirements for reactor design, environmental and social safeguards, and the modeling of downstream losses of carbon dioxide.
The Enhanced Weathering in Closed Engineered Systems Module requires suppliers to meet three key criteria to ensure the durable storage of carbon dioxide:
- Provide comprehensive documentation of reactor design and maintenance.
- Take direct measurements of all inputs and outputs from the reactor.
- Robustly model the downstream losses of carbon dioxide once the bicarbonate ions are discharged and reach the ocean.
This module was developed in line with the Isometric Standard and was created through collaboration between Isometric’s in-house Science Team and reviewers from Isometric’s independent Science Network of over 300 academic experts.
Leading engineered EW suppliers—Capture6, Limenet, pHathom, Planeteers, and Vycarb—provided extensive feedback during the development of this module.
