2 HN users recommended this demo1 month2022–2025score 1
Years with an HN recommendation, 2007–2026
HN commenters cite it as an entertaining reality check on home gravity storage, showing the yield is tiny compared to household needs.
Quint BUILDs tests a rooftop water storage setup in which solar power pumps water up to the roof and a turbine generates power later. He works through the numbers to show how much energy it actually stores.
There is a great youtube channel that tests out different energy storage and harvesting setups, a lot of them focused around water. This is one where they use solar to pump water to the roof, and then use the potential energy overnight: [this video]
Solar pumps water to the roof, then generates power overnight.
Here's some "slow math" in video form ;) [this video] I find him entertaining. Put a 55 gallon drum on his roof, pumping water up via solar and running lights at night. Closed loop system. He also "does the math" and mentions exactly what you are saying in entertaining format. Just not worth it if you're not doing it on a massive scale, preferably way out of sight and danger.
Entertaining rooftop water storage that does the math on scale.
Sounds like this one: [this video] They do say it is about equivalent to a single AA alkaline. It is not exactly an optimized efficient setup, but still, it gets the point across. Pumped hydro is a grid scale option, in places that have the ability to store a lot of water.
Home solar-pumped water storage that yields about one AA battery.
> maybe they mean 2 MWh, but if that's the case, it is a joke. That's like 30 Teslas cars Reminded me of the punchline to this water storage video: [this video] That guy went mechanical with rocks: [link]
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