The performance of a novel high speed zinc electrowinning system using a hydrogen anode and an aluminium rotating disc cathode (1 m diam.) was investigated under various experimental conditions. This new type of zinc eleotrowinning system was continuously operated at a current density of 70 Adm(-2), which is twelve times higher than that usually employed. Current efficiency is 90% at 50 A dm(-2) in an electrolyte containing 60 g dm(-3) Zn + 160 g dm(-3) H2SO4, the zinc purity being at least 99.999%. The energy usage of the system is 1650 kWh per tonne of zinc, 380 m(3) of H-2 gas being required.