Plans for world's first tidal power plant

[adam2]

I wonder if this means that the project will actualy be built ? Or is this simply the go-ahead for another round of studies, consultations, enquiries and nimbyfests in general.

This project or something very similar has been "approved" or "going ahead" for at least seven years.

[Mark]

I wonder if this means that the project will actualy be built ? Or is this simply the go-ahead for another round of studies, consultations, enquiries and nimbyfests in general.

This project or something very similar has been "approved" or "going ahead" for at least seven years.

Every method of obtaining power has implications - my feeling is that this is at the low end of the scale in terms of environmental impact and running costs, but probably high in terms of construction costs... should be good in terms of energy resilience too - the more diverse sources we have, the better...

The Senedd election is on 6th May - interesting to see if this features at all ?
Imagine that Plaid Cymru will be all in favour, not only for the economic boost...
The more control a country has over the basics - water/energy/food etc., the bigger the bargaining chip...

[BritDownUnder]

I saw a lovely 'glossy' video about the project on this website and all the companies based in the UK that will benefit if the project goes ahead.

Nice if all the work and construction went to the UK. I do feel it is a bit big to be a test bed and probably a less complex project, at least in terms of civil works, should be tried first. However the UK is running out of time now and maybe this is as good as it will get.

I heard a mention of 'variable speed induction generators' that got me thinking though as this likely means the project will not be able to provide full grid support as a fossil or nuclear fuelled synchronous generator power station could.

With regard to electoral support, a lot of forum members seem to live in South Wales these days so maybe it should be up to them to at least mention it to any election candidate they come across.

[Mark]

Seems like the engineering is moving on too ?
https://www.building.co.uk/comment/why- ... 46.article
https://www.newcivilengineer.com/latest ... 5-03-2021/

Current thinking is that the future of tidal energy lies in tidal lagoon power stations. These enclose an area of coastline with a high tidal range behind a breakwater, with the footprint carefully designed for the local environment. The Swansea Bay Tidal Lagoon was billed as a world first, with an estimated capacity of 320MWh, but it would have only been able to operate 14 hours a day, and unavoidable issues regarding construction costs, environmental impact and long-term value have put plans on hold indefinitely.

However, we are edging closer to finding solutions to these challenges. Over the last decade, I have been working with a single goal in mind: a renewable energy system that produces power 24 hours a day, every day, to make tidal power viable. Such a solution is vital in the drive towards Net Zero by 2050. At TPGen24, the tidal energy research centre I founded, we’re testing a lagoon system with the potential to deliver on the above, and more.

Progress has been steady, but breakthroughs in 2020 make the system we’re developing hard to ignore now. Currently being tested, we will be looking to bring it to a wider audience this year, demonstrating a tidal power technology which can provide huge benefits and deliver long-term value. Further, the proposed, advanced design of this plant, which combines smart technology and traditional engineering, differentiates our system from what has come before it. Crucially, it will be equipped to generated electricity 24/7, 365 days a year. Not only will it realise my ambition for tidal power, but also make a far more compelling business case for investment in renewables than ever before.

[BritDownUnder]

I found a nice long report all about tidal lagoons.

[kenneal - lagger]

Tidal power has a slack point at high at low tides every day but it is only for a couple of hours and the timing varies around the coast of the UK: the timing is also know for hundreds of years in advance so measures can be put in place to cover any shortfall. Also there are at least two types of tidal flow generation: the lagoons and the turbine type (wind turbine lookalikes). Strangford Loch in Northern Ireland and the research centre off the coast of the north of Scotland have the turbine type functioning now.

The turbine type of tidal generation is much cheaper as they only require some sort of foundation on the sea floor rather than an embankment. They are also much smaller than a wind turbine as the density of the water that turns their blades is about 800 times higher than the air that turns a wind turbine although the water velocity is lower by a factor of ten or so. They do, however, have to be much more robust due to that weight of water hitting them.

I am surprised that more water turbines have not been installed. That is probably due to the higher cost per turbine and the difficulty of working under water and or fully waterproofing the generation system.

[Mark]

The Swansea lagoon might be coming back from the dead....., or will Mostyn beat them to the punch.....?

Dozens of companies register interest in developing a tidal lagoon off Welsh coast:
https://www.walesonline.co.uk/news/wale ... y-20745132
North Wales tidal lagoon takes step forward after positive seabed studies:
https://www.business-live.co.uk/economi ... s-19510208

[adam2]

It is possible to generate tidal power continually throughout 24 hours at one site, but this adds considerable cost and complexity and is unlikely to find favour.
TWO lagoons are needed, "high" and "low" At high tide the high lagoon is opened to the sea via sluice gates which are closed when the tide starts to ebb.
The low lagoon is opened to the sea at low tide, via sluice gates that are closed as the tide rises.
The water levels in the two lagoons will vary, but there will always be a difference, which can be used to generate power 24/7.

I mention this only for completeness, multiple sites with different tide times are more likely to be viable.

[adam2]

The Swansea lagoon might be coming back from the dead....., or will Mostyn beat them to the punch.....?

Dozens of companies register interest in developing a tidal lagoon off Welsh coast:
https://www.walesonline.co.uk/news/wale ... y-20745132
North Wales tidal lagoon takes step forward after positive seabed studies:
https://www.business-live.co.uk/economi ... s-19510208

Glad to hear of this. More employment, more low carbon electricity, and less reliance on foreign powers for electricity (or gas used to generate electricity)

[kenneal - lagger]

There is a tidal power plant in France. At Rance, built in 1966 and there was one built in South Korea in 2011.

https://en.wikipedia.org/wiki/Rance_Tidal_Power_Station

It's about time that we built at least one though.

[adam2]

Some time ago, I met a senior engineer in the UK wind power industry.
They were strongly in favour of the proposed Bristol Channel tidal barrage, and in particular spoke of the merits of a combined tidal power and wind turbine installation for the following reasons.

1) The barrage will be a huge civil engineering job, and building wind turbine towers as part of the barrage should be cheaper than as separate structures.

2) Lighthouses or warning beacons will be required to warm mariners of the barrage, these may be incorporated into the wind turbine towers.

3) Locks will be required to permit the passage of ships and boats, these will require visual observation and radar, easily achieved from a suitably placed wind turbine tower.

4)A Large high voltage grid connection needed, probably duplicated, cheaper to provide at one location than two.

They suggested four large wind turbines, one at each end and one each side of the locks near the middle.
A road along the length of the barrage would provide opportunities for walking, cycling, sightseeing and angling. Suitable for a fire engine or ambulance in case of emergency, and for vans or light trucks for maintenance. not open for road traffic otherwise.

[BritDownUnder]

The Grauniad is talking about the Severn Barrage again due to the Ukraine crisis. Probably just talk, going on past history.

It was talked about in the 1800s. Nothing happened.
It was talked about in the 1930s. Nothing happened.
It was talked about in the 1980s with the report from the unusually named Sir Herman Bondi. Nothing happened.
It was talked about in the ten years ago. Nothing happened.
Will anything happen? Probably not.

To answer the last post I don't think 4 turbines will have any material effect on the power output. The largest wind turbine is the GE Haliade rated at 12 MW so 48 MW in total. The generally accepted output of the Severn barrage at Weston Super Mare is around 8000 MW.

[adam2]

As has already been suggested, this tidal barrage may be back in favour due to the war in Ukraine.

And as regards the proposal to add wind turbines to the project, the extra power thereby produced is indeed small if compared to the tidal power, that however is not the point. Of more relevance is the reduced construction costs of wind turbines built as part of the tidal power barrage, if compared to stand alone wind turbines.

[adam2]

This post from the nuclear forum suggests that the Severn Barrage was found uneconomic, rather than being out-NIMBYied as I suspected.

"Re: Proposed new nuke at Wylfa
Post by clv101 » Sun Mar 27, 2022 5:40 pm

adam2 wrote: ↑Sun Mar 27, 2022 4:59 pm
Firstly tidal power proposed in the Bristol Channel was rejected due to the nimby factor. This was widely reported as being a "great victory for local people" An not as a setback for green energy.
That may have been reported but I'm sceptical. IMO the most significant reason for its rejection was simply cost. It was looking significantly more expensive than Hinckley C which made it a non starter."

That suggests to me that this project should go ahead, in view of the present high electricity price, and doubts as to gas supplies from which a lot of our electricity is generated.

Even if NOT ECONOMIC this should still go ahead in my view. Wind power was hopelessly uneconomic when new, but is now viable.

[clv101]

Conventional economics don't work well or the tidal barrage. It lasts too long so its benefits 50, 70+ years into the future are discounted away to nothing. Had the 'uneconomical' thing been built in the 1970's it would today, be doing a lot better than the decommissioned fleet of nuclear reactors with theier ~£100bn+ decommission cost.