World’s largest tidal scheme gets public nod

The Mersey Tidal Power Project could be installed in the River Mersey between the northern English city of Liverpool and the Wirral. Depending on the design selected, the barrage could be up to 3km long.

The project, being led by the City Region Combined Authority, is in its fledgling stages, with the formal planning process not yet even begun, but a recent consultation by Liverpool City Council found that 92% of respondents were in favour of it in principle.

The option being considered is a barrage option, rather than a lagoon, as it is the cheapest and would enable a link between Liverpool and the Wirral for the first time, forming a bridge on the top of the turbines.

The barrage would have an operating lifespan of at least 120 years.

Onshore flood protection, rock armour and breakwaters would also be needed, and port facilities would have to be up to scratch for the additional use required.

“A range of other ancillary developments and facilities may also be required as part of the Project including access, utility connections, boundary treatments, security infrastructure, temporary and permanent laydown areas, hard and soft landscaping, drainage, cables, plant, and equipment,” say the project details.

Steve Rotheram, Mayor of the Liverpool City Region, said: “The River Mersey has been the lifeblood of our region’s fortunes for centuries – and it has an even more vital role to play in our future. Where our area was once a leader in the First Industrial Revolution, we now have an opportunity to seize our chance to become a leader in the Green Industrial Revolution.

“We are under no illusions, we know there are still significant technical and financial challenges to overcome, but the plans we’ve unveiled mark a huge step on our journey to bringing Mersey Tidal Power to life.”

Similar projects

Liverpool City Council has been working with K-Water, the water company in South Korea that built the Sihwa Lake tidal barrage, which has been operating since 2011.

As well as generating electricity with its ten 25.4MW turbines, the circulating seawater cleaned up the lake water, which was seriously polluted. Each turbine generates 100MW.

When built, Sihwa was the largest tidal barrage in the world – but this could change if Liverpool’s goes ahead.

To help with the project, officials from K-Water have signed an ‘innovation deal’ with Liverpool to cooperate, share their knowledge.

The world’s first tidal power station, and before Sihwa Lake’s was built, the largest, was developed in Brittany, France on the Rance River.

The 750m long installation generates 240MW, and has a history of almost 60 years, having been completed in 1967.

Although plans are not finalised, the Liverpool plant has been estimated to have a generational capacity of about 700MW from 28 turbines, powering around 1 million households.