Producing one kilogram of hydrogen through conventional electrolysis requires approximately 9 kilograms of water, creating additional pressure on freshwater supplies as electrolyzer deployment expands. UK-based Hychor, a spin-off from the University of Aberdeen, is developing a seawater-based hydrogen production system designed to address this limitation by eliminating the need for freshwater treatment before electrolysis.
The company’s approach focuses on enabling direct seawater electrolysis for off-grid and coastal applications, where access to renewable electricity may be available but freshwater infrastructure is limited. The technology is aimed at reducing one of the practical barriers to scaling hydrogen production: the dependence on purified water streams.
Hydrogen is increasingly viewed as a potential complement to electrification in sectors where batteries remain technically limited, including aviation, shipping, and high-temperature industrial processes. However, the production pathway remains a major determinant of whether hydrogen can deliver meaningful emissions reductions.
Today, most hydrogen is still produced from fossil fuels, primarily through processes such as steam methane reforming, which generates significant carbon emissions unless combined with carbon capture technologies. Green hydrogen produced through water electrolysis avoids direct emissions when powered by renewable electricity, but the economics remain challenging due to high electricity demand, electrolyzer costs, and infrastructure requirements.
Water availability adds another layer of complexity. Conventional alkaline and proton exchange membrane electrolyzers require treated water because impurities can reduce efficiency, damage components, or create unwanted chemical reactions. While seawater is abundant, directly using it in electrolysis has historically been difficult because dissolved salts introduce operational risks.
The main technical challenge comes from chloride ions naturally present in seawater. During electrolysis, chloride can lead to the formation of chlorine compounds, including chlorine gas, which is highly reactive and can accelerate corrosion within electrolyzer systems. Existing seawater hydrogen approaches often rely on desalination before electrolysis, but that step adds energy consumption, capital costs, and waste management challenges.
Hychor’s system attempts to address this issue by redesigning the electrolysis process rather than treating seawater as a problem to be removed. The company was founded around research conducted by CEO Jani Shibuya, whose doctoral work focused on electrocatalyst surface behavior, sustainable flow batteries, and desalination technologies.
According to Hychor, its technology uses seawater salts as part of the conductivity process instead of attempting to eliminate them before hydrogen production. The company has not publicly disclosed detailed electrolyzer architecture because its patent application is still under development, but it states that the process does not require additional chemical additives and does not generate unwanted by-products.
The potential advantage of the approach is that it could reduce both freshwater demand and the environmental complications associated with desalination. Conventional seawater hydrogen systems that incorporate desalination can produce concentrated brine streams, which require careful disposal to avoid localized impacts on marine environments.
Hychor claims its process increases seawater concentration by less than 1%, allowing the treated water to be returned directly to the marine environment. If validated at scale, this could differentiate the technology from other seawater electrolysis concepts that require separate desalination and brine management systems.
However, commercial viability will depend on whether the system can maintain efficiency, durability, and cost competitiveness compared with established electrolyzer technologies. Electrolyzer degradation remains one of the central challenges for hydrogen developers, particularly in harsh operating environments where impurities, temperature fluctuations, and variable renewable power can affect performance.
For offshore and remote hydrogen production, these considerations are especially important. Renewable projects located near coastlines, islands, and remote industrial sites often face infrastructure limitations that make freshwater supply expensive or impractical. A seawater-based solution could theoretically enable hydrogen production closer to renewable energy sources and reduce dependence on long-distance transport.
Hychor plans to begin a pilot project in 2027, targeting coastal and off-grid locations where direct seawater access and renewable electricity could provide operational advantages. The company’s technology reflects a broader trend in the hydrogen sector: moving beyond improving individual components and instead redesigning entire production systems around resource constraints.
