The goal to satisfy the energy demand, global warming and other environmental effects has prompted the urgency to shift energy generation systems to more affordable and sustainable methods, with the goal of phasing out the traditional-conventional systems to environmental friendly and sustainable generation systems. This campaign also calls for a more energy conscious society aware of its energy demand and promoting energy efficiency so as to minimize the demand through reduced wastages. For the later to be achieved energy systems should be understood in organization and this involves performing energy audits.

This paper discusses the energy audit of Nchanga mine, Nchanga mine is located in Chingola town in the Copperbelt province of Zambia, and has operations involving underground mining, copper leaching, open pit mining and concentrate extraction. The Objective of the study was to perform a preliminary Audit; to understand the energy scenario and identify areas were savings could be realized. The problem however was that constraints on time could not allow a detailed analysis hence the scope was strictly on a preliminary audit study with minimal details on economics of measures and no analysis of investment cost. The method used for this analysis was the top down approach and the processes were divided into support and production processes to establish the energy balance.

Nchanga mine has an annual energy use of about 656 GWh with an average maximum demand of about 88.6 MW. The total cost was about US. $ 34 million with maximum demand (MD) covering about $ 22 million and the rest was energy costs. This was obtained from analysis of energy bills from April 2011 to March 2012. The energy measures analyzed were according to the cost; cost influenced and non-cost influenced. The non-cost influenced measures gave a saving potential of about 15.6 MW ($ 3.9 million) on MD and 46 GWh ($ 818,800) on energy, giving a total electricity cost saving of about $ 4.7 million. The cost influenced measures gave a saving potential of about 12.7 MW ($ 3.1 million) on MD and 12 GWh ($ 213,600) on energy, giving a total electricity cost saving of about $ 3.4 million. These measures have a potential to reduce the overall MD by 28 MW (32% reduction), realizing an annual saving of about $ 7 million, and the overall energy use by about 58 GWh (8.8% reduction), which is an annual saving of about $ 1 million. This gives the total saving on the electricity bill of about $ 8 million that is about 24% reduction on the electricity bill with regards to last year’s expenditure.