Planners of the 3.2GW output plant aim to produce cheaper electricity than Hinkley Point
Plans to develop a tidal lagoon power station big enough to supply every home in Wales have taken a step forward with the announcement of the project developer, Tidal Lagoon Power (TLP), has secured a grid connection for the 3240MW station. Located between Cardiff and Newport, the tidal lagoon is projected to be the first full-scale deployment of this technology, following on from a pilot scheme planned for Swansea Bay.

The Swansea scheme is now fully-consented and awaiting final sign off from the government, a decision which is expected within weeks, but TLP is keen to secure the next phase of its plans. Although it does not expect to submit a full application for development consent for the Cardiff Bay tidal project until 2019, it has been working on advance plans for three years and has now accepted an offer for grid connection from National Grid Electricity Transmission plc.
“Our offer to the UK government is to contract Swansea Bay Tidal Lagoon for a lower subsidy per megawatt hour than Hinkley Point C,” said TLP’s chief executive Mark Shorrock. “While we await the government’s response to this offer and to the independent Hendry Review of tidal lagoons, we have continued our development work on the subsequent programme.
“Today we have secured the grid connection for a tidal power station equal in installed capacity to Hinkley Point C. Looking at the pounds per megawatt hour unit cost of new build power stations, nuclear is currently priced in the nineties, the latest offshore wind projects are expected to drop into the seventies and our models show Cardiff Tidal Lagoon beating them all in the sixties.”
The projected Cardiff Bay project comprises a 20.5km breakwater wall enclosing some 70 km2 of the Severn Estuary and housing up to 108 tidal turbines within at least two powerhouses. These would handle flows of some 600million cubic metres of water on each tidal cycle. TLP estimates that over 3000 construction workers will be needed to build the lagoon and its associated systems, supporting a further 8000 jobs in the supply chain in Wales and throughout the UK, with supply contracts potentially worth over £6bn. It is hoping to secure some £8bn of investment to complete the project, and is also working on projects in Colwyn Bay, Bridgwater Bay and West Cumbria, as well as discussing some international projects.
TLP notes that the lagoon can also operate as pumped hydro power, and its agreement with National Grid will allow it to handle up to up to 2,171MW of flexible load from Cardiff Bay. “This could be timed to facilitate the integration of more intermittent wind and solar power and more inflexible nuclear power into the future energy system,” it claims. “A portfolio of geographically dispersed tidal lagoons could further enhance these system benefits.”
TLP was this month announced as one of the winners of The Engineer’s Collaborate to Innovate Awards for its plans for the Swansea Bay pathfinder project, along with partners Atkins and LDA Design. Engineers closely involved with the project will be speaking at the Awards’ associated conference on 7 December in Coventry.
This smells of Jam tomorrow. The case for the Swansea scheme is weak and depends upon the greenness of politicians. The power is predictable at least, but is still intermittent. The cost of supporting intermittent generation is conveniently forgotten in the subsidies and is an additional penalty on the cost of power.
The UK is moving towards being one of the highest cost of electricity countries in the world rapidly, the trouble is that the damage will not be credited to the present politicians etc, but for the next generation to live with.
Today’s news states offshore wind is even cheaper.
http://www.bbc.co.uk/news/business-41220948
Two firms said they were willing to build offshore wind farms for a subsidy of £57.50 per megawatt hour for 2022-23.
The tide has definitely turned against the nuclear industry.
Far more tidal lagoon schemes all around Britain’s coast are required, operating as pumped hydro power.
Finally, this scheme comes a step nearer to fruition.
Green, dependable energy at its best plus proven technology.
If there is a political will, this might provide power before Hinkley Point C.
This all seems a bit vague – and with caveats eg “appropriate locations”. And is flooding good or bad? Or more precisely what happens to the flow of the water down a river.
I thought that it was not a subsidy (strike price) that was being offered, for nuclear. And talk about solar/wind being cheaper raises the issue of the marginal cost – i.e. backup or storage – and the issue of needing a sure power supply all day and all year – which is possibly more important (and valuable) than power at certain times.
As Julian says, the value of power is related to its reliability. In days gone by, unreliable generation was charged with the cost of spinning reserve required for when the source failed. This charge is not invoked on wind and wave, as it ought to be, making stand-by very uneconomic.
Australia are considering refurbishing and re-using their old coal fired power stations as back-up / load followers. Our green-MPs are determined to get rid of our excellent old coal fired stations in the name of the AGW dogma and for no measurable change in global CO2 : regardless of the consequences.
I am in the unusual situation of once being involved in two tidal power projects. One of them was even larger than Cardiff. In spite of our efforts, both turned out to be seriously uneconomic.
The capacity factor is claimed to be 21% which reflects the fact that it is based on generating only during ebb tides and that, during neap tides, the generation will fall off by more than 50%.
The cost/benefit analysis no doubt excludes the extra costs that will be imposed on the system for providing extra power when the turbines are not operating or during neap tides, the cost of absorbing surplus power when it is not needed and the cost of the very substantial transmission line needed. These costs will fall on the hapless consumer.
It is also unfair to compare the estimated cost of the project – which will no doubt rise substantially – with the cost of Hinkley point, a nuclear station that should never have got off the ground. An accurate comparison would include the total cost of providing a reliable and consistent supply of tidal power when it is needed with the cost of a modern gas-fired power stations or modern nuclear power stations in serial production..
Sounds as if you would have been in a good position to make comments and give a critical (and useful) context to what seems to be a publicity/marketing article
Hi Bryan
Good to hear from someone involved in this type of project. When you say uneconomic, is that compared to gas / coal or compared to other tidal projects?
Uneconomic compared to coal/gas and nuclear. No tidal power scheme has been costed sufficiently accurately to rank them with any confidence.
As has been said many times on these comment threads; the only problem we face in the West is the (‘free’ market) political ideology of the fools ruining Great Britain. (The EU, the US, etc.) e.g. under this article:-
https://www.theengineer.co.uk/the-rise-of-the-green-dragon/
All well-informed politicians should know, innovation has to be, “led, assisted and facilitated by government rather than left to market forces and entrepreneurs.” The innovation we need here is the RAEng’s proposed Minehead to Aberthaw barrage, which is superior to 3 nuclear plants, but would cost less. The government excluded that option from the (Severn) feasibility study. In that location, the barrage would protect Hinkley Point from a storm surge or tsunami.
Designed with ‘before-generator’ energy storage, its power would be dispatchable, as would all the wave/wind power connected to it. It would outlive three generations (200 years) of nuclear plant. Electricity from La Rance barrage costs under €0.02/kWh. . . the cheapest option, bar none. “Jam tomorrow” is a very attractive proposition for the grandchildren, I’d say. Anything less is selfish and irresponsible.
New, clean, sustainable generating capacity is an essential infrastructure investment that can only be economically built by the state. The sole purpose of any subsidy is to guarantee private equity a big fat return on investment. Our industries and consumers will have to foot that bill.
The cost/benefit analysis invented to make a case for HS2 is another political fantasy. If the train companies refuse to invest in infrastructure, it shouldn’t be built. (according to the ideology!)
If the electricity industry refuses to invest in tidal power, should the government subsidise it? NO!
Electricity from La Rance barrage costs under €0.02/kWh.
It was built in the 1960s. At the presentation I attended, EDF refused to provide info on costs and never built another. Go figure!
Stop trying to concrete over the world.
Regardless of Jack’s jaundiced AGW dogma, I doubt he’d describe old coal-fired stations as “excellent”, if he lived near Aberthaw. Same goes for nuclear power advocates – NIMBY, thank you!
The BBC reports that Ecotricity’s millionaire founder, Dale Vince, is critical of TLP’s Swansea plans. He says the Swansea lagoon is more of a regeneration project and should be paid for by the tax-payer, not bill payers. I agree, excellent idea. The local authority should own it. If the economics of its electricity generation are poor, it will still be a valuable municipal asset for future generations. The government should direct infrastructure investment to deprived communities in the UK, and not spend so much on wealthy areas like London and the Midlands.
Today I received an invitation to the Regeneration Conference & Exhibition, Cardiff, on Oct. 3-4, but I ask myself, “What good does it do?” Nobody listens to the voice of reason. The government has shelved plans for rail electrification in this part of the UK.
I caution the authorities to delay before final approval of funding and construction of these tidal lagoon schemes so that the plans’ proposed inferior single lagoon design can be upgraded to the superior double lagoon design, as explained in my post –
Double Tidal Lagoon Baseload Scheme
I propose a renewable energy scheme where a tidal lagoon is partitioned into a ‘high’ lagoon and a ‘low’ lagoon by a dividing wall, which houses turbines which continuously generate power as sea water flows from the high lagoon to the low lagoon.
Operation
At high tide, the sea-gates of the high lagoon are opened and the high lagoon is filled up to high tide level.
When the ebb tide begins, the sea-gates of the high lagoon are closed and remain closed until the next high tide.
At low tide, the sea-gates of the low lagoon are opened and the low lagoon is emptied to low tide level.
When the flood tide begins, the sea-gates of the low lagoon are closed and remain closed until the next low tide.
The sea-gates are functionally identical to one-way flap valves and may be engineered as such.
Baseload
The Double Tidal Lagoon Baseload Scheme delivers a genuine baseload generation capability which can’t be delivered by inferior single tidal lagoon schemes as proposed by Tidal Lagoon PLC, as explained in the critical review in Energy Matters, “Swansea Bay Tidal Lagoon and Baseload Tidal Generation in the UK”.
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I would hate any delay to put these projects in jeopardy and I’d rather see the less-than-optimal single lagoon design built than lose this project altogether.
I’m a friend of these tidal lagoon projects but as a friend, I think a bit of tough love is needed so as to insist on the better double lagoon option.
Tidal lagoons are a very simple and scientifically sound technology. (Not that you need a scientist to tell you that because the basic method has been in use for hundreds of years.)
Response to Dave Smart’s comments on my comments:
1. All AGW debate has an element of dogma as neither anthropogenic warming nor its absence can be proved with the data available. My cynicism is about the Al Gorythms applied to homogenise the measured data and reliance on a seriously flawed computer model.
2. The coal fired power stations of the UK have given magnificent service for over 40 years and meet every regulation required of them. They have been massacred, along with electricity costs, by blind acceptance of AGW requiring carbon penalties to be applied to coal (not wood).
3. Aberthaw was designed to burn anthracitic coals and has given 45 years of low cost power whenever it was demanded.