I remember in the late 2000s (I think) EWS trialled 92s+HTA on Mossend to Arpley coal workings, I think it was only a couple of runs though. Although the Ardrossan to Hunterston freight line isn’t wired, Hunterston I believe had a “beetle” on one loading line that could drag wagons through the loader, so that could have solved the loading challenge had the terminal been wired. Academic now really as big chunks of it, including one of the big cranes, had been demolished last time I was down that way.I'm pretty sure no builk freight of the type carried in hopper wagons is electrically hauled in the UK, but what do other countries use for overhead loading terminals?
If you’re looking for the most famous UK electric hauled hopper working, I guess you need to go back to coal over Woodhead, but, IIRC, those workings were diesel at either end & only electric from (correct me please!) Wath to Reddish?