Every second it is running, Hinkley Point C power station will suck in 134 cubic meters of seawater. The water will travel three kilometres through pipes towards the reactor. There the cold water from the Bristol channel will meet superheated waters of a steam turbine. Any fish that had been caught up in this journey, would return to the channel lightly poached due to the heat.

But, scientists have found a surprising solution to the problem – a fish disco. This is the colloquial name for an acoustic deterrent system designed by scientists from Swansea University that, according to a new study, could help save 90% of fish from the power plant’s water intake pipes. 

The system uses 300 underwater speakers which emit sound pulses to repel fish from the River Severn away from the power plant’s pipes. It is predicted to help save about 44 tonnes of fish a year – the equivalent to the annual catch of a small fishing vessel.

When testing, the scientists found that only one of its tagged twaite shad fish came within 30 metres of the intake pipes when the “disco” was on, compared to 14 when the sound system was turned off. 

The disco comes with a hefty price tag of £700m which has attracted some controversy – though this amounts to just 1.5% of the total cost of building the £46bn project. 

EDF Energy, which is building the Hinkley powerplant, has said the system will give Britain’s first new nuclear power plant in a generation “more fish protection than any other power station in the world.”

The energy company previously argued against fitting the requirement, and instead suggested constructing salt marshes to help protect marine life. 

Special mouths will also be attached to the intake pipes, which will slow the water suction and allow fish to escape within two metres from the entrance of the pipes. 

Dr David Clarke, a fisheries scientist and marine ecologist at Swansea University, said: “These early results are very encouraging with the system clearly working. Our results show that a large majority of the tagged shad avoid an area extending some 60 metres from the intake heads protected by the acoustic fish deterrent system.”

Chris Fayers, the head of environment at Hinkley Point C, said: “Because the system works even better than we had hoped, it means we can meet all of our planning obligations and should not need to create 900 acres of salt marsh as environmental compensation. And it’s good news for a power station that will generate the reliable, low carbon electricity that the country needs.”

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