The system is based on an underwater pumped storage concept that replaces conventional upper and lower reservoirs with a sealed, pressure-resistant hollow sphere deployed on the lakebed or seabed. The surrounding water body serves as the “upper reservoir,” while the interior of the sphere functions as the “lower reservoir.”
Sadly i didnt see any energy numbers in the article to get a feel for how many kWh this thing stores. Probably not much at all, but still a cute idea i guess.
Dumping thousands of these into the ocean is probably much more economical than building the same amount of 65m tall water towers. Because thats basically all that this is. Would probably be much more resource efficient to go a lot deeper though, like the 600m deep Fraunhofer project they mentioned. As long as it costs less than 10x as much to build its better value.
I would still guess lifting water through pipes (specially if the reservoir is uphill in a mountain) is way easier than building something chained at the bottom of the ocean, which would need pulleys and a big heavy weight down there.
Oh now I found time to read the article. I thought they would sink and rise hollowed balls, when they actually keep the balls down and pump water in and out of them.
I wonder if they are heavier than water, so you just need a small anchor to prevent drifting.
Huh. So instead of sending water up a big ass tower to store energy, they’re sinking giant ping pong balls? Neato!