returned energy dump

Hi,

On the files section there is a PDF-file called returned energy dump
(its in the map circuits). I was wondering if anyone as ever tried
it. I'm using three gecko 201, almost at their maximum (70V 7A each).
So i definitely need something between my power supply and the
gecko's. If I just use a zener diode, as recommended by Geckodrive
the energy can't go back in the power supply so were does it stay?

Thanks

Hugo