A few years ago there was a slew of articles about storing energy by lifting and stacking heavy blocks of concrete.
I have no idea how efficient those designs are compared to hydro storage but I imagine they solve a problem for regions where there is no suitable site for the water reservoir.
Haven't seen that concept in the news recently, maybe it didn't pan out?
Physics isn't very kind to all these gravity-energy-storage ideas. You need very large objects and substantial height differences to store any meaningful amount of energy.
While many ideas about new types of gravity-energy-storage are flaoting around, pumped hydro is the only gravity-storage technology that ever worked in practice.
And even pumped hydro isn't in a great spot. Batteries are essentially competing for the same market (intra-day storage, few hours, high round-trip efficiency), and improving fast.
I have no idea how efficient those designs are compared to hydro storage but I imagine they solve a problem for regions where there is no suitable site for the water reservoir.
Haven't seen that concept in the news recently, maybe it didn't pan out?
https://spectrum.ieee.org/gravity-energy-storage-will-show-i...
https://www.wired.com/story/energy-vault-gravity-storage/