The Energy Vault is a Dumb Idea, Here's Why

What people said

perpetuallunch · 2026-08 · Criticism

> Or lifting a really heavy thing and letting it fall slowly. I challenge you to run the numbers on this. Or at least read or watch someone who has. Whenever you’re certain you know the answer, it behooves to try to prove yourself wrong. Unsurprisingly, gravity is an extraordinarily weak force. It merely appears otherwise because the total mass of the Earth is literally astronomical at around the 5.9722×10^24 kg mark. Concrete blocks hanging from a crane, much less so. Don’t believe me. BIY - Believe It Yourself here: [VIDEO] Pumped hydro is a nonstarter: do you see any suitable geography anywhere ? Yep, they’ve already been dammed damn it. So approximately no one ^ can have their existing hydro upgraded to pumped hydro retro fitted to pumped, and have the surrounding landscape covered in solar and wind. How helpful! Chemical batteries? South Australia has a decent sized one. I think it can power some of the state for about 12 seconds.^^ ^okay, not no one: Hydropower accounts for approximately 15% , but you have to choose pumped hydro sites where it also makes sense for wind and / or solar, so it’s clearly not an answer for everyone everywhere. Not even close. ^^hyperbole! I know. Look, it’s actually around 1–1.5 hours, which is statistically closer to my estimate of 12 seconds than anything actually useful like a day or a week.

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donquichotte · 2024-02 · Criticism

My thoughts exactly. It makes the engineer in me go mad if I see projects like Energy Vault [1] getting massive funding that could be used to try and develop technologies that make sense. Thankfully there are some people who see through the charade [2]. If you are into this thing and looking for an even more stupid idea to store energy, I present to you the StEnSEA [3]. Rolls right off the tongue, right? It is a hollow concrete sphere that is lowered to the bottom of the lake. Pumps then remove water from it, creating a vacuum. Letting the water back in and using the pumps as generators, the energy is reclaimed. Curiously absent from all documentation of this project is the amount of energy stored. I did some back of the envelope calculations a while back and it is 3.8kWh, for a multi-million-euro prototype! [1] [LINK] [2] [VIDEO] [3] [LINK]

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smt88 · 2022-11 · Criticism

This is a stupid idea, and there are some great YouTube videos that explain why[1]. tl;dr We already move enormous amounts of drinking water, and reservoirs are much better (and cheaper) candidates for batteries than sand/cement/etc. 1. [VIDEO]

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