Experts are warning that EDF’s plans to replace a proven Acoustic Fish Deterrent with a high-frequency battery-powered device at Hinkley Point C will not protect all species or deliver long-term reliability.
An eight-year delay has resulted in what Fish Guidance Systems describes as a significant downgrade. The business, a world leader in proven acoustic and behavioural fish deterrent technology, is today raising concerns about EDF Energy’s proposal for the Hinkley Point C nuclear power plant.
EDF’s new plan replaces the originally designed acoustic fish deterrent system, which was intended to stop an estimated 182 million fish per year from being killed in the power plant’s cooling water intakes.
Instead, a battery-powered acoustic device will be implemented. Based on current evidence, it does not offer adequate protection for all aquatic species and could leave regulators unaware of whether the array is operating at required levels or not. The system only works on shad, and does not yet have a long operational track record at the scale and duration required for a major nuclear power station.
Careful consideration needed
High-frequency acoustic systems are known to have no impact for certain species, including salmon, and the proposed system will therefore require additional measures to ensure full protection. The use of higher frequencies also introduces different acoustic characteristics to those originally approved, which require careful consideration of potential impacts on marine mammals such as harbour porpoise and minke whale.
Changes in acoustic frequency affects how fish and marine mammals behave, not just whether they are deterred from an intake. High-frequency sound can disrupt migration, schooling and breeding, which is why the originally approved low-frequency system was designed to operate continuously and predictably.
Dr Andy Turnpenny, who helped scope the original Acoustic Fish Deterrent Plan for Hinkley Point C stated “The purpose of an AFD is to generate a warning signal to deter fish. Of the hundred or so species at risk, the ultrasound system proposed will only deflect shad.”
Requiring long-term resilience
Dr David Lambert, environmental scientist and director of Fish Guidance Systems, explained the proposed change represented an unnecessary risk for both wildlife and the operation of the nuclear power plant.
He said: “After resisting the government-mandated acoustic fish deterrent system for nearly eight years, EDF is now proposing an alternative approach that raises important questions. We are pleased to see the installation of an acoustic fish deterrent, but decades of experience tell us that high-frequency, battery-powered systems alone will not deliver comprehensive protection across all species or the long-term resilience required for a nuclear facility.
“This is not about opposing novel systems. It is about ensuring that the final system meets the original environmental and operational objectives set for Hinkley Point C.”
Fish Guidance Systems has successfully installed its acoustic and behavioural fish deterrent systems worldwide. These systems, deemed best practice in the UK by the Environment Agency, prevent species including salmon, trout and herring from entering cooling water intakes at large industrial facilities.
The proven technology is working at energy plants worldwide. Fish Guidance Systems has worked for decades to design, install and maintain acoustic and behavioural fish deterrent systems at large-scale, safety-critical infrastructure. Its focus has consistently been on protecting marine life while ensuring reliable plant operation, based on long-term, real-world performance.