In Liverpool, plans for a ‘mega project’ for tidal energy are taking shape

The River Mersey and the City of Liverpool.

Ingus Kruklitis / Eyeem | Eye | Getty Images

  • The iconic River Mersey could soon play a major role in the UK’s sustainable future.
  • Authorities in Liverpool want the river to be home to a massive tidal energy project that they say could power as many as 1 million homes.
  • The first proposals for a tidal barrage across the Mersey were formulated as early as 1924.

The River Mersey is one of Europe’s most iconic waterways. As well as being an important hub for shipbuilding and industry, it has been a source of inspiration for a large number of writers, artists and musicians over the years.

If all goes according to plan, the Mersey could also play an important role in the UK’s sustainable future.

Authorities in Liverpool want the river to be home to a massive tidal power project that they say could power as many as 1 million homes, creating thousands of jobs for the region in the process.

If built, the facility would have a capacity of at least 1 gigawatt and would make use of the Mersey’s tidal range, the second highest in the UK.

Learn more about energy from CNBC Pro

Speaking to CNBC, Martin Land, director of the Mersey Tidal Power Project, outlined how the system would work in practice.

The idea, he explained, is to center it on the creation of “a structure to hold back the tide, or to control the tide — we let the height build on one side and the other side has a low level .”

“And then we let that water, that seawater, go through turbines and generate electricity,” he added. “So it uses the potential energy, the height difference of the tide.”

This arrangement is different from installations using tidal current turbines, which, quite simply, often resemble submersible wind turbines.

Land told CNBC that the project is nearing the end of its concept phase, with a number of scenarios on the table.

“We still have an option for a barrage site, which would cross from the Birkenhead side… the left bank of the Mersey, to the right bank, the Liverpool side,” he said. “Or it could also be a lagoon.”

A tidal barrage spanning a body of water resembles a dam. The International Renewable Energy Agency describes tidal lagoons as similar to a barrage, but adds that “they are not necessarily connected to the coast” and “could be in the ocean”.

Tidal barrier systems currently in operation include EDF’s 240 megawatt La Rance tidal power station in France, and South Korea’s 254 MW Sihwa Lake tidal power station, currently the largest in the world.

The first proposals for a tidal barrage spanning the Mersey were formulated in 1924. The current project has taken a number of steps forward in recent times.

In December 2022, an agreement was signed with the Korea Water Resources Corporation, the owner and operator of the Sihwa Lake facility.

In a statement at the time, the Liverpool City Region Combined Authority said K-Water had agreed to “share tidal energy knowledge”.

The agreement, it added, would see “K-water and the Combined Authority working closely together to explore tidal energy opportunities.”

The Combined Authority in Liverpool is optimistic about the prospects for its tidal energy project, stating on its website that “the age of tidal energy has come” thanks to technological improvements and the climate crisis.

In a statement to CNBC, Steve Rotheram, mayor of the Liverpool City Region, struck a similar note.

“Once operational, Mersey Tidal Power would have the potential to become the world’s largest tidal power system,” he said.

Stock Picks and Investment Trends from CNBC Pro:

Tidal power plants have been around for decades — EDF’s La Rance dates back to the 1960s — but a number of projects have made major strides in recent years.

For example, in February 2023, a company headquartered in Edinburgh said its tidal stream array had achieved a world first by producing 50 gigawatt-hours of electricity.

And in July 2021, a tidal turbine weighing 680 tonnes began grid-connected power generation at the European Marine Energy Center in Orkney, an archipelago north of mainland Scotland.

Plans were announced in October of the same year for a £1.7 billion (approximately $2.05 billion) project integrating technologies including underwater turbines in waters off Swansea, a coastal city in Wales.

As with many renewable energy projects around the world, concerns have been raised that the development of a large tidal power station in the Mersey could have a significant impact on the environment.

Cheshire Wildlife Trust, for example, states it is “zealous to support renewable energy programs in the right place”, but adds that “a barrage project in the Mersey Estuary has the potential to cause significant environmental damage”.

More generally, the U.S. Energy Information Administration notes that a “potential downside to tidal power is the effect a tide station may have on plants and animals in tidal basin estuaries.”

“Tidal currents can change the tidal level in the basin and increase turbidity (the amount of matter suspended in the water),” it adds. “They can also affect navigation and recreation.”

As noted earlier, at this stage it has yet to be decided whether the planned scheme for the Mersey will be a dam or a lagoon.

For his part, Martin Land of the Mersey Tidal Power Project tried to emphasize that there were “well-developed guidelines on the environmental impact assessment that you have to do for mega projects… for big infrastructure projects.”

“We know that when developing project options we need to consider the impact of a plan on the river and estuary and also whether it can help with the regional problem of rising sea levels,” he added.

Proposals for the Mersey Tidal Power Project represent yet another example of how the UK aims to harness its vast coastline and become a force in the emerging marine energy sector.

While there is excitement about the plans, there is still a huge amount of work to be done to get the development off the ground.

Any design will need to include navigation locks for the large number of vessels, both large and small, that navigate the river.

If fully realized the cost of the project would be significant – the Liverpool City Region Combined Authority is calling it a “billion pound development”.

The scale of the project will undoubtedly require support from the central government in London, a point Rotheram acknowledged in his statement to CNBC.

“We have demonstrated that we have the skills, capabilities and political will to make Mersey Tidal Power a success,” he said.

“Now we just need the government to match our ambition with the funding to make it happen.”

During his interview with CNBC, Martin Land echoed Rotheram’s point.

“The government’s action will give us the confidence to move forward,” he said. “We want to move to single scheme selection this year.”

“And we’d like to get into the formal consent process so we can go ahead with construction and have this up and running at an early stage. [20]the 30’s.”


Leave a Reply

Your email address will not be published. Required fields are marked *