Tidal Lagoons

Terraformer · 2024-03-14 10:50:18

Tidal barrages have been proposed as a source of renewable yet dispatchable energy. Unfortunately they, well, trash the ecosystem of whatever bay you've enclosed to build one. Tidal lagoons have been proposed as an alternative that will mostly leave the intertidal zone alone, being built beyond the low water mark.

https://en.wikipedia.org/wiki/Tidal_power#Tidal_lagoon

However tidal energy is not the only role lagoons could play. Such lagoons would provide areas of calmer water out at sea and provide space for aquaculture. Potentially with the water being treated to remove contaminants like plastic and mercury? Dogger bank is a notable fishing ground, due to its shallowness; we could create an artificial seabed if we wished to help macroalgea (getting into artificial island territory here, despite still being submerged...). As for generating power, I believe Calliban has talked about hydraulic accumulators for wind power before? A lagoon could be mechanically pumped full of water by windmills (vertical axis!) with a single joint turbine for electricity generation, giving us wind power that at least fluctuates on a scale of hours instead of seconds.

tahanson43206 · 2024-03-14 11:11:50

This post is reserved for an index to posts NewMars members may contribute over time.

Best wishes for success with this interesting new topic.

(th)

Terraformer · 2024-03-14 13:49:45

I envisage building them using concrete (unreinforced... at least with iron) pontoon bases that are floated out and flooded to settle them on the ocean floor. The way the Maunsell forts were constructed -- https://en.m.wikipedia.org/wiki/Maunsell_Forts

The walls perhaps would be made of basalt fibre reinforced concrete. The structures would need to be joined together before flooding, unless there is a sufficiently strong grout that can set underwater.

Yes, I am aware the details of this plan are lacking, like how to deal with a seafloor that isn't a consistent depth.

Terraformer · 2024-03-14 13:58:10

I probably should have named the topic Artificial Lagoons rather than Tidal Lagoons, since I'm not only interested in them for tidal power. I would love to see Dogger Bank dotted with lagoons.

Regarding construction, it occurs to me that the lagoon doesn't have to extend all the way to the seabed; so long as the towers are strong enough to contain the weight of the additional water vs sea level (6-7m in the case of tidal power), we will be able to use a false seafloor only a few metres below the surface. Of course, if the false seafloor is itself bouyant, essentially being anchored to the seabed and contained by the pillars, then the bouyancy would take the water weight...

Calliban · 2024-03-14 19:25:10

For the UK especially, tidal energy has a lot of potential. Total tidal energy in UK waters averages at 200GW. This compares to 30GWe baseload electricity consumption (as of 2024).
https://pubs.aip.org/aip/jrse/article/1 … dbacks-and

Globally, resources are more modest and the favourable locations seem to be geographically isolated. But this could be an important resource for us Britons. Ecological considerations have limited development to small scale tidal stream projects so far. Maybe we will see more in the future.

I like the idea of concrete pontoons for Dogger bank. It would be a good place to build a detention centre for all the third world trash that keeps floating into Britain. Amongst other uses of course :-)

Last edited by Calliban (2024-03-14 19:31:13)

New Mars Forums

Announcement

#1 2024-03-14 10:50:18

Tidal Lagoons

#2 2024-03-14 11:11:50

Re: Tidal Lagoons

#3 2024-03-14 13:49:45

Re: Tidal Lagoons

#4 2024-03-14 13:58:10

Re: Tidal Lagoons

#5 2024-03-14 19:25:10

Re: Tidal Lagoons

Board footer