The manufacturing industry is increasingly accountable for the environmental impact resulting from its activities. Research indicates that specific production processes within manufacturing plants generate significant environmental impact through energy consumption. To understand the consumption of energy in a production environment, it is necessary to outline the energy flow within the facility, along with the classification of energy usage and its relationship to processes and production outputs. It is also important to identify auxiliary (non-value added) energy within production as the area with the greatest potential for savings through changes in operational behaviour. This article introduces a practical process mapping methodology that combines energy management with value stream mapping. The methodology is based on ‘Lean’ manufacturing principles and on application to a couple of industry use cases has been shown to successfully illustrate the relationship between the energy usage and production activities for a particular value stream. Furthermore, the significant energy users in relation to the actual production process steps have been identified, and energy reduction opportunities of 42% and 50% have been quantified.