Demand-side management of energy seeks to foster energy efficiency investments and curtailment behaviour in households. The role of environmental concern and knowledge for both types of energy saving behaviour has hardly been investigated in middle income countries with growing middle classes and rising electricity demand. Drawing on unique household survey data from Ghana, Peru and the Philippines, this paper analyses the links from individual motivation to behaviour, and from behaviour to the impact on households' total electricity expenditures. We find that consumers with more environmental concern are more likely to adopt curtailment behaviours, but that concern does not influence energy efficiency investments. In turn, higher levels of environmental knowledge make households' energy efficiency investments more likely, but do not influence curtailment. Neither energy efficiency investments nor curtailment behaviours significantly impact households' electricity expenditures. Small differences between Ghana, Peru and the Philippines exist.