Concrete weights stacked to store energy and destacked to provide output.
It works (of course) but will have difficulty being cost competitive with
other storage technologies.


https://qz.com/1355672/stacking-concrete-blocks-is-a-surprisingly-efficient=
-way-to-store-energy/

Claimed end to end efficiency is around 85%.
LiIon efficiency said to be around 90%. (Actual figure depends on methods
of charge/discharge).

________________________________

A "train" (or multiple units) on a track with cable connection may allow
improved ease of charge/discharge.
Energy storable per mass is less per distance moved due to non-vertical
track, but can make use of long slopes.
The excessively enthused could move 'wagons' sideways at top and bottom to
increase capacity.

A single looped cable would allow multiple 'wagons' to be pulled up or to
descend using existing chair-lift type coupling/decoupling.

Masses & heights involved are "somewhat daunting"

1 kWh =3D 3,600,000 watt-seconds
~=3D 360,000 kg.m  (100% efficiency)  =3D eg
360 tonne x 1m
36 t x 10m
3.6t x 100m
360 kg x 100 x 10m
36 kg x 1000 x 10m
....



Russell
--=20
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