Oxford firm wins major backing for fin-based tidal power

Oxford-based Caudal Energy has raised £4.3 million to support full-scale testing and development of its fin-based tidal power system, with plans to deploy its technology commercially by 2028.

The funding round was led by Oxford Science Enterprises (OSE) and Empirical Ventures, with additional investment from Zero Carbon Capital and Creator Fund.

John Kennedy, CEO of Caudal Energy, said: “The future energy system needs renewable power that is not only clean, but dependable and built to scale.

“We founded Caudal to challenge the assumption that tidal energy has to remain complex, costly and niche.

“Our approach combines smarter hydrodynamic design with modular deployment architecture to create a system designed for real-world performance.

“By unlocking the potential of mid-flow tidal sites, we believe Caudal can dramatically expand where tidal energy can be deployed and how commercially competitive it can become.”

Mr Kennedy added that the funding enables the company to demonstrate the technology at a commercially relevant scale and accelerate the path towards ‘delivering predictable renewable power as a meaningful part of the future energy mix’.

Caudal’s modular, surface-mounted system is designed to operate in mid-flow tidal locations, expanding the range of sites where tidal power can be generated.

The company said the technology, currently at Technology Readiness Level 5, will be tested at Strangford Lough in Northern Ireland, with a target of reaching commercial deployment and Technology Readiness Level 8 by 2028.

Caudal Energy was established in 2024 based on hydrodynamic research by co-founder Professor Adrian Thomas of the University of Oxford.

Inspired by the movement of marine mammals, the system uses oscillating foils to convert tidal flows into energy.

The funding represents one of the most significant recent institutional venture investments into tidal energy in the UK, and will be used to expand Caudal Energy’s engineering and modelling capabilities, advance demonstration and deployment activities, and accelerate commercial partnerships across utility, industrial and distributed energy markets.

Andy Straiton, investment lead at Oxford Science Enterprises, said: “Caudal Energy is addressing one of the most important challenges in the transition to renewable energy: how to provide predictable, scalable generation that complements intermittent power sources such as wind and solar.

“Importantly, Caudal’s approach is designed around the economics required for large-scale deployment, not just technical performance.

“The combination of simpler deployment, lower operational complexity and access to a far broader range of viable sites can make tidal energy cost competitive with established renewables such as solar and wind.”

Caudal Energy is in active talks with strategic partners as it moves toward a commercial-scale demonstration of its technology.