CO2 permanently stored in rocks
44.01 turns CO₂ into rock, harnessing the natural power of mineralization. Their technology injects CO₂ into peridotite, an abundantly available rock, where it is stored permanently. This storage approach can be paired with a variety of capture technologies.
Storing CO2 as bicarbonate in the ocean
Ebb Carbon mitigates ocean acidification while capturing CO₂. Using membranes and electrochemistry, Ebb removes acid from the ocean and enhances its natural ability to draw down CO₂ from the air for storage as oceanic bicarbonate.
A nature-based soil amendment that sequesters carbon
Eion accelerates mineral weathering by mixing silicate rocks into soil. Their pelletized product is applied by farmers and ranchers to increase carbon in the soil, which over time makes its way into the ocean where it’s permanently stored as bicarbonate. Alongside their technology development, Eion is also conducting a novel soil study to improve the field’s measurement of CO₂ uptake.
Direct air capture technology
Sustaera uses ceramic monolith air contactors to capture CO₂ directly from the air for permanent storage underground. Their direct air capture system, powered by carbon-free electricity and built with modular components, is designed for quick manufacturing and capture at scale.
Sequester CO2 through the ocean
Seachange leverages the power and scale of the world’s oceans to remove carbon. Their experimental electrochemical process sequesters CO₂ in seawater as carbonates, an inert material comparable to seashells, thereby enabling energy-efficient and permanent CO₂ removal.
Ocean alkalinity restoration and photosynthesis
Running Tide removes carbon by growing kelp in the open ocean. After maximum growth, the free-floating lines of kelp sink to the deep ocean where the embodied carbon is stored for the long term. Running Tide’s approach is simple and scalable, powered by photosynthesis, ocean currents and gravity.
Absorbing CO2 from ambient air
Over geological timescales, CO₂ chemically binds to minerals and permanently turns to stone. Heirloom is building a direct air capture solution that enhances this process to absorb CO₂ from the ambient air in days rather than years, and then extracts the CO₂ to be stored permanently underground.
Electrochemically removing CO2
Mission Zero electrochemically removes CO₂ from the air and concentrates it for a variety of sequestration pathways. Their experimental room-temperature process can be powered with clean electricity and has the potential to achieve low costs and high volumes using modular, off-the-shelf equipment.
Direct air capture stored as concrete
CarbonBuilt’s process readily converts dilute CO₂ into calcium carbonate, creating a “no compromise” low-carbon alternative to traditional concrete. As a profitable and scalable solution for permanent CO₂ storage, CarbonBuilt’s technology platform can serve as a critical component of future carbon removal systems using direct air capture.
Trialing accelerated mineral weathering
Future Forest is conducting a field trial to accelerate mineral weathering by crushing basalt rocks into dust, spreading them onto the forest floor, and then measuring CO₂ uptake. This first-of-a-kind trial will help assess the potential for scale as well as the potential ecosystem impacts associated with enhanced weathering.
Renewable geothermal energy
Climeworks uses renewable geothermal energy and waste heat to capture CO₂ directly from the air, concentrate it, and permanently sequester it underground in basaltic rock formations with Carbfix. While it’s early in scaling, it’s permanent, easy to measure, and the capacity of this approach is theoretically nearly limitless.
Storing carbon in concrete
CarbonCure injects CO₂ into fresh concrete, where it mineralizes and is permanently stored while improving the concrete’s compressive strength. Today they source waste CO₂, but represent a promising platform technology for permanent CO₂ storage, a key component of future carbon removal systems.
Carbon removing sand
Project Vesta captures CO₂ by using an abundant, naturally occurring mineral called olivine. Ocean waves grind down the olivine, increasing its surface area. As the olivine breaks down, it captures atmospheric CO₂ from within the ocean and stabilizes it as limestone on the seafloor.
Converting biomass and permanently storing it
Charm Industrial has created a novel process for preparing and injecting bio-oil into geologic storage. Bio-oil is produced from biomass and maintains much of the carbon that was captured naturally by the plants. By injecting it into secure geologic storage, they’re making the carbon storage permanent.