Purpose – The purpose of this paper is to provide a comparative overview of existing energy system models to see whether they are suitable for analysing energy, environment and climate change policies of developing countries. Design/methodology/approach – The paper reviews the available literature and follows a systematic comparative approach to achieve its purpose. Findings – The paper finds that the existing energy system models inadequately capture the developing country features and the problem is more pronounced with econometric and optimisation models than with accounting models. Originality/value – Inaccurate representation of energy systems in the models can lead to inaccurate decisions and poor policy prescriptions. Thus, the paper helps policy makers and users to be aware of the possible pitfalls of various energy system models.