Energy Consumption vs. Head Grade 0 10,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000 90,000 % % % % % % % Ore Head Grade (% Cu) Cu) ROM Leach SXEW Crush Leach SXEW SABC Smelt HPGR Smelt SABC HT ConLeach SABC MT ConLeach HPGR MT ConLeach Total energy consumption as a function of ore head .