California-based carbon removal company Captura has begun operations at its latest pilot plant in Kona, Hawaii, designed to capture 1,000 tonnes of carbon dioxide (CO2) annually. Developed in partnership with Equinor, the facility represents a key step in advancing Direct Ocean Capture (DOC) technology, which extracts CO2 from seawater to enhance the ocean’s natural ability to absorb atmospheric emissions.
The ocean absorbs around 30% of global CO2 emissions, making it a crucial carbon sink. DOC technology removes CO2 directly from surface waters, allowing the ocean to draw additional CO2 from the atmosphere. The process requires no feedstock, generates no waste, and can be scaled to remove significant amounts of carbon.
Captura’s DOC system combines electrodialysis and gas extraction with widely available water and gas handling technologies. Two previous pilot plants in Los Angeles demonstrated the technology’s effectiveness, and the Hawaii facility will validate its performance on a larger scale. The company is now designing its first commercial facility, expected to capture tens of thousands of tonnes of CO2 annually.
“This facility in Hawaii is the last milestone before widespread commercial deployment of DOC technology,” said Steve Oldham, CEO of Captura. “Its rapid installation and commissioning in just over two months demonstrate the scalability of our solution.”
In Hawaii, the captured CO2 will support local industries, including aquaculture, to reduce their carbon footprint.
The plant is based at the Hawai’i Ocean Science and Technology (HOST) Park, managed by the Natural Energy Laboratory of Hawaii Authority (NELHA), which has overseen ocean research in Kona for more than 50 years. The park’s environmental monitoring programme will complement Captura’s research on ocean health.
