A technology demonstrated to be more efficient than pumped hydro is steel wheels on rails.
https://www.google.com/search?q=elec...orage+railroad
http://www.aresnorthamerica.com/
Their demonstrator uses miles of existing track with typical grades in Nevada. I think a better solution would be a cog or
rack railway.
For a home installation, a stack of barbell weights that traverses a flagpole on cables and pulleys.