Here is someone who drove up a mountain then back down and calculated how much battery charge was regained.
Net result...46% SOC to start, down to 36% at the top and regained to 40% at the bottom.
So he regen'ed 4% out of 10% (plus or minus something)...but he got back about 40% of the energy he used going up.
Now maybe there was a rounding error and maybe the conditions weren't ideal -- you decide.
Tested the Regen system by climbing 100-3800ft and back down.
