This seems like it could mess up local weather by bringing up water of different temperatures if deployed at scale (and if not at scale, what's the point?).
My understanding of this technology is that it's closed-circuit. No water is exchanged between the power plant and the ocean once filled with ocean water.
[Company] has tested a small model of the reservoirs in wave tanks and off the coast of Reggio Calabria, Italy. It’s now deploying a pilot of the floating components in advance of a full demonstration plant. By 2026, it’s hoping to deploy several commercial projects at sites around the world.
At full size, the turbines would generate around 6 to 7 megawatts of electricity each, and there will be one for every 100 meters of pipe. Deeper sites would have more storage potential, and each commercial site would host multiple reservoirs. Sizable hopes to deliver energy storage for €20 per kilowatt-hour (about $23), about one-tenth what a grid-scale battery costs.
—-
Testing in calm reservoire is different from potentially .wild offshore (ocean/sea)
What happens to 100-200 m long pipe in underwater waves when e.g. a hurricane or a storm comes?
Wait a second $23/kWh? I pay ~ $0.15/kWh for power at my residence the majority of the year. Is this a proof of concept number? What am I not understanding such that the power this produces is 4 orders of magnitude more expensive than what’s in place currently?
What I don't understand is how the top reservoir is floating when filled with brine. Are the small floaters enough to hold it up?
Otherwise I love the fact that's simple. Simplicity scales.
It's also salt water, so assuming they're not putting anything else than NaCl, it can break and it's no big deal
The maintenance on this will be a real killer and by the time you build the robotic infrastructure to maintain it you’re not a power company anymore kindof how Amazon isn’t a bookseller.
It sounds quiet inefficient to me. The energy differential comes from the different salt concentrations, so you have to move a lot of water to exploit a relatively low mass differential.
Mentions of efficiency are conspicuously absent from the article.
Another potential problem is marine ecology: pumping high-salt sea water to the top and releasing it en masse might lead to much larger fluctuations in salt concentration than what the ecosystem is used to.
That said, we need many different approaches to solve energy storage, and I hope to be wrong, and that they end up very successful.
Relying on a salinity differential, even between salted and unsalted, seems like a terribly small amount of energy. There are projects to put large spheres at the feet of offshore windmills to pump water in and out. That has some pressure challenges but store a lot more.
The advantage I see for the salinity difference is that you can make them a lot larger than the pumped water ones. But is worth it, I'm skeptical.
- they concentrate salt water once to get "heavier than sea water" brine. Hope not chlorinated.
- it's then a closed system shuffling between bottom and top tank(s)
- everything floating is soft, so no strong forces unless a wave crashes on top
- advantage of ocean: "free standing" within height/depth margins, free water for initial fill
And really not visible in the video:
- the disk you see floating is a V shaped bladder with the storage in the V below surface and floatation sprinkled all around and segmented in to "cake wedges".
16 comments
[ 6.0 ms ] story [ 29.8 ms ] threadHow many big cities are there on earth with that depth available nearby?
[Company] has tested a small model of the reservoirs in wave tanks and off the coast of Reggio Calabria, Italy. It’s now deploying a pilot of the floating components in advance of a full demonstration plant. By 2026, it’s hoping to deploy several commercial projects at sites around the world.
At full size, the turbines would generate around 6 to 7 megawatts of electricity each, and there will be one for every 100 meters of pipe. Deeper sites would have more storage potential, and each commercial site would host multiple reservoirs. Sizable hopes to deliver energy storage for €20 per kilowatt-hour (about $23), about one-tenth what a grid-scale battery costs. —-
Testing in calm reservoire is different from potentially .wild offshore (ocean/sea)
What happens to 100-200 m long pipe in underwater waves when e.g. a hurricane or a storm comes?
Otherwise I love the fact that's simple. Simplicity scales. It's also salt water, so assuming they're not putting anything else than NaCl, it can break and it's no big deal
Mentions of efficiency are conspicuously absent from the article.
Another potential problem is marine ecology: pumping high-salt sea water to the top and releasing it en masse might lead to much larger fluctuations in salt concentration than what the ecosystem is used to.
That said, we need many different approaches to solve energy storage, and I hope to be wrong, and that they end up very successful.
The advantage I see for the salinity difference is that you can make them a lot larger than the pumped water ones. But is worth it, I'm skeptical.
- they concentrate salt water once to get "heavier than sea water" brine. Hope not chlorinated.
- it's then a closed system shuffling between bottom and top tank(s)
- everything floating is soft, so no strong forces unless a wave crashes on top
- advantage of ocean: "free standing" within height/depth margins, free water for initial fill
And really not visible in the video:
- the disk you see floating is a V shaped bladder with the storage in the V below surface and floatation sprinkled all around and segmented in to "cake wedges".