A German Experiment Proved That Simple Concrete Spheres Make Fantastic Batteries. Now, California Plans To Submerge A 9-Meter Diameter Sphere In The Ocean And Is Already Planning Versions Of 30 Meters
Each sphere has an estimated lifespan of between 50 and 60 years, with partial replacement of components every 20 years or so.
The concept is fascinating, but what I'm most curious about is how they achieve that longevity in seawater. Benthic life really loves to settle and build on hard surfaces.
The concrete isn’t the problem. Like mentioned above, the sealife growth is. Also, metal and moving mechanicals are savaged by seawater (and the sealife growth). Keeping things working on the surface of the water is difficult and expensive. Water pressure makes that even worse. Maintenance requires divers which are likewise very expensive.
I think the sea has a huge potential of energy production that is totally untapped because of that.
There are tons of ways to produce energy with sea water but as soon as you put any moving parts in water it gets corroded and covered with benthic life (I've learned a word today). Every project of ocean energy production dies because of that.
I would imagine it wouldn't matter how many barnacles and stuff are on it. That's the outside. Everything important is inside, I'm assuming the intake water will be screened or filtered in some way.
Most benthic life (by number) start as tiny, motile creatures. Screens would reduce head pressure and require maintenance. Barnacles of all kinds, as an example critter, settle on everything to which they can adhere. I'm guessing the engineers considered these complications since there have been past power project failures because of sea life. I wish the article went into those mitigations. If it's somehow a non-issue by nature of the design, my curiosity is even more piqued.