This CEEC Medal-winning paper summarizes a comprehensive energy and cost study comparing an existing SAG mill based circuit at Huckleberry Mine  with two proposed circuits involving comminution technologies which are associated with energy efficiency: high pressure grinding rolls (HPGR) and high speed stirred mills. Results showed that the HPGR – ball mill circuit achieved a 21% reduction in energy consumption over the existing SAG – ball mill circuit at the same P80 grind size of 160 μm. At a grind of 80% passing 75 μm, the HPGR – stirred mill circuit showed a 34% reduction in energy compared to the base case. It was concluded that the energy reduction for the new flowsheets significantly improved the economics of the Huckleberry comminution duty.