The iron and steel sector is the second-largest energy consumer and main emitter of greenhouse gases in the Brazilian industry. We present a unique, detailed analysis of the energy performance of a sample of five integrated mills with internal coke production that account for over half of the crude steel produced in Brazil and identify economically viable energy efficiency measures. The analysis indicates that the specific total energy consumption of this sample of mills increased by about 13% between 2004 and 2014 and that the corresponding figure for electricity consumption was 18%. Performance and cost data on best energy practices for iron and steel production processes applicable in Brazilian mills are used to develop fuel and electricity Conservation Supply Curves. The economic potential identified for fuels was 3.02 GJ/t of crude steel, which can be achieved with nine energy efficiency measures, mainly in the iron making, sintering and steel making processes. The findings also indicate that these mills could become net exporters of electricity with an economic potential of 1.51 GJ/t of crude steel if four energy efficiency measures were implemented, particularly in the O-2 production and coke making processes. (C) 2018 Elsevier Ltd. All rights reserved.