Welsh tidal lagoon project could open way for £15bn revolution in UK energy

A prototype system of dams and turbines in Swansea Bay could provide Britain with a major zero-carbon source of power

The Guardian, Robin McKie Science Editor, Saturday 8 October 2016

An artist’s impression of the Swansea Bay tidal lagoon scheme.
Photograph: Tidal Lagoon Power/PA

Backers of an ambitious proposal to transform the UK’s power supply will learn in the next few weeks if they are to be given the go-ahead to build tidal lagoons to generate electricity. The green light could see a series of major lagoon projects costing more than £15bn being constructed around the coast of Britain.

A tidal lagoon generates electricity from the natural rise and fall of the tides. Rising water flows into dams many miles in length, driving turbines. It is then held back behind walls as the tide recedes before being released to drive the turbines again, generating thousands of megawatts of power.

A prototype is set for construction in Swansea Bay in the next few years – but only if it is given the go-ahead by a government review of tidal lagoon technology, chaired by the former energy minister Charles Hendry, which is scheduled to release its recommendation early next month. 

Green energy experts believe Hendry will give approval, although it remains to be seen if tidal lagoon technology – which was backed strongly by the former chancellor George Osborne in the last Conservative manifesto – finds favour with Theresa May’s administration.

Mark Shorrock, chief executive of Tidal Power Lagoon, the backer of the Swansea Bay prototype lagoon, said the technology could be an important zero-carbon source of electricity generation for the UK. “In addition, the money to build tidal lagoons will come from British investors and the expertise and technology we develop could be sold around the world,” he said. Tidal lagoons could also provide much of the power needed to make up for the predicted shortfall in UK energy that will be caused by the phasing out of coal plants and ageing nuclear reactors over the next decade, he added.

Six major projects have been earmarked for construction: a prototype at Swansea Bay; and then full-size lagoons at Cardiff, Newport, Colwyn Bay, Bridgwater Bay and west Cumbria. “The crucial point about tidal lagoons is that their power generation is not subject to the vagaries of the weather. It is predictable. We know exactly when every high tide will be for years ahead. In addition, the lagoons will be built to last – for about 120 years,” Shorrock said.

The £1.3bn Swansea Bay prototype has been designed to generate 350 megawatts of power – enough to supply 150,000 homes with electricity – and could be in operation by 2019. About 11 square kilometres of the bay would be surrounded by a 9km wall. Cycle paths would be built on the walls and a sailing and canoeing centre would be set up inside the lagoon.

Tides would sweep water into the lagoon and drive an array of 16 turbines, generating electricity. Then, after high tide has passed, the stored water would be released to pour back out of the lagoon to drive the turbines in the opposite direction – and generate more electricity. Shorrock claims the lagoon would be able to produce power for about 14 hours a day.

The £1.3bn Swansea Bay Tidal Lagoon project consists of an 9km sea wall 

and an array of 16 dual-directional turbines, designed to harness the 

energy of the Atlantic’s tidal surges

As the tides rise and fall the lagoon fills and empties. Regardless

 of the direction of the flow, the six-metre tall turbines will generate electricity

Swansea Bay electricity would cost around £89.90 per megawatt hour, he added, compared with the £92.50 per megawatt hour price predicted for electricity from the Hinkley Point C nuclear plant. “However, when we scale up operations with the Cardiff lagoon – which will have 10 times the generating capacity of Swansea – we will be able to produce power for £65 a megawatt hour,” he said.

The Cardiff lagoon would cost £9bn to construct and contain 65 square kilometres of water within a 20km wall. It would have a capacity of 3,000 megawatts of electricity – compared with the proposed 3,200 megawatts from Hinkley Point C.

A request for planning approval for the Cardiff lagoon is to be made by 2018 with the aim of establishing a manufacturing industry for lagoon components in the UK.

However, it is the speed of this follow-up that worries many green campaigners. Most back the idea of the Swansea Bay test project but some fear that construction of much larger follow-up schemes – starting in Cardiff Bay but going on to Colwyn and Bridgwater shortly after – could begin too soon to adopt any lessons that will be learned from construction of the prototype lagoon.

This point was stressed by Mark Robins, of the RSPB. “The Swansea tidal lagoon could prove to be very useful but we will have to monitor how the first prototype affects the movement of silt in the estuary, disrupts bird populations and impacts on fish stocks before we scale up. This is a completely new technology and it is going to be built in a very complicated natural site – the Severn estuary. We need to be very careful how we go.”

Richard Benwell, of the Wildfowl and Wetlands Trust, agreed. “We are cautiously welcoming,” he said. “However, we would want the scheme’s impact to be very carefully monitored before building started on the next-generation lagoon at Cardiff.”

However, there is strong pressure from the scheme’s backers to instigate a speedy follow-up of the Swansea lagoon. They want to establish a supply chain for generators, turbines and other components to kick-start tidal technology in the UK, establish a series of major lagoon generators and eventually become the world leader in the field.

Some worry about the environmental dangers. Others stress the advantages for local economies around Wales and Liverpool where tidal lagoons are likely to be clustered.

“This could become a global industry that started in the UK yet was not linked to the EU,” said Jane Davidson, pro vice-chancellor at the University of Wales Trinity Saint David and a former Welsh Assembly minister. “This could play a major role in subsidising low-income, lower-skills areas. It is something that, locally, we can pick up and run with.”

For its part, the UK climate change committee counselled caution in its report on renewable energy last year. “There may be a role for tidal lagoon power in providing predictable low-carbon electricity in the UK if projects can be delivered at acceptable cost. However, it is important that these proposals proceed with careful assessment of the potential environment impacts,” it warned.

Related Articles:

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Green light for world’s largest planned tidal energy project in Scotland

Pentland Firth tidal turbine project given consent
Giant tidal turbine 'performing well' in tests off Orkney


"Recalibration of Free Choice"–  Mar 3, 2012 (Kryon Channelling by Lee Caroll) - (Subjects: (Old) Souls, Midpoint on 21-12-2012, Shift of Human Consciousness, Black & White vs. Color, 1 - Spirituality (Religions) shifting, Loose a Pope “soon”, 2 - Humans will change react to drama, 3 - Civilizations/Population on Earth,  4 - Alternate energy sources (Geothermal, Tidal (Paddle wheels), Wind), 5 – Financials Institutes/concepts will change (Integrity – Ethical) , 6 - News/Media/TV to change, 7 – Big Pharmaceutical company will collapse “soon”, (Keep people sick), (Integrity – Ethical)  8 – Wars will be over on Earth, Global Unity, … etc.) - (Text version)

“…  4 - Energy (again)

The natural resources of the planet are finite and will not support the continuation of what you've been doing. We've been saying this for a decade. Watch for increased science and increased funding for alternate ways of creating electricity (finally). Watch for the very companies who have the most to lose being the ones who fund it. It is the beginning of a full realization that a change of thinking is at hand. You can take things from Gaia that are energy, instead of physical resources. We speak yet again about geothermal, about tidal, about wind. Again, we plead with you not to over-engineer this. For one of the things that Human Beings do in a technological age is to over-engineer simple things. Look at nuclear - the most over-engineered and expensive steam engine in existence!

Your current ideas of capturing energy from tidal and wave motion don't have to be technical marvels. Think paddle wheel on a pier with waves, which will create energy in both directions [waves coming and going] tied to a generator that can power dozens of neighborhoods, not full cities. Think simple and decentralize the idea of utilities. The same goes for wind and geothermal. Think of utilities for groups of homes in a cluster. You won't have a grid failure if there is no grid. This is the way of the future, and you'll be more inclined to have it sooner than later if you do this, and it won't cost as much.

Water

We've told you that one of the greatest natural resources of the planet, which is going to shift and change and be mysterious to you, is fresh water. It's going to be the next gold, dear ones. So, we have also given you some hints and examples and again we plead: Even before the potentials of running out of it, learn how to desalinate water in real time without heat. It's there, it's doable, and some already have it in the lab. This will create inexpensive fresh water for the planet.

There is a change of attitude that is starting to occur. Slowly you're starting to see it and the only thing getting in the way of it are those companies with the big money who currently have the old system. That's starting to change as well. For the big money always wants to invest in what it knows is coming next, but it wants to create what is coming next within the framework of what it has "on the shelf." What is on the shelf is oil, coal, dams, and non-renewable resource usage. It hasn't changed much in the last 100 years, has it? Now you will see a change of free choice. You're going to see decisions made in the boardrooms that would have curled the toes of those two generations ago. Now "the worst thing they could do" might become "the best thing they could do." That, dear ones, is a change of free choice concept. When the thinkers of tomorrow see options that were never options before, that is a shift. That was number four. ….”