Climate change mitigation urgently requires not only drastic emission reductions but also active removal of CO₂ from the atmosphere. To limit global warming to 1.5–2 °C and avoid severe and potentially irreversible impacts on ecosystems and societies, IPCC scenario analyses indicate that net negative emissions must emerge within the coming decades and scale to multiple gigatonnes of CO₂ per year later in the century.

Direct Ocean Capture (DOC) is emerging as a technically robust and potentially scalable pathway for ocean-based CO2 removal. By exploiting the ocean’s large alkalinity reservoir, pH-sensitive carbonate equilibria, and high dissolved inorganic carbon content, DOC enables carbon removal at concentrations far exceeding those in air. This makes it attractive for durable and verifiable CO₂ removal with a limited land footprint, while also offering co-benefits such as localized mitigation of ocean acidification.

Rapid progress in electrochemical system design, advanced materials, and integration with renewable electricity has moved DOC from theoretical concept toward applied technology. A growing ecosystem of start-ups, research institutes, and industrial actors is now actively developing DOC solutions, reflecting increasing confidence in its long-term role within a diversified carbon removal portfolio.

Despite this momentum, DOC remains at an early stage of maturity. Most systems are confined to laboratory or small pilot scales, with limited evidence from continuous operation in real marine environments. Major technical hurdles include high electricity demand, corrosion and fouling in saline conditions, and inefficiencies in CO₂ separation, concentration, or mineralization. Beyond engineering, progress is also constrained by the lack of harmonized environmental assessment methods, clear regulatory pathways, and robust monitoring, reporting, and verification (MRV) frameworks.

This presentation reviews the core principles of DOC and explains how electrochemical processes can selectively manipulate seawater chemistry to remove CO2 for permanent storage or utilization. It then highlights an industrial–research collaboration between VTT and Mitsubishi Electric. Through a recently signed memorandum of understanding, VTT and Mitsubishi Electric have launched a long-term partnership focused on nature-positive technologies addressing marine and climate challenges. Within this framework, a joint DOC R&D program targets accelerated commercialization through piloting and demonstration, combining system development, field-relevant testing, techno-economics, and sustainability considerations. Together, these efforts aim to move DOC from laboratory promise toward real-world climate impact.