The development of a global model incorporating Climate, Land, Energy and Water (CLEW) parameters and interconnections was undertaken using the Open Source Energy Modelling SYStem. The model was to be a simplistic representation of the nexus systems and include the most relevant mechanisms between them. Two separate modules on land use and materials were created and combined with an already existing energy module. Water and climate parameters were added to all modules and they were combined to the global CLEWs Base model. Three scenarios were run on the separate sector modules and the combined model. Results from the comparison of the separate and combined modules indicate that the CLEW approach is applicable even on a simplistic, highly aggregated scale. Differences in resource allocation were observed when the same parameters were run in the single sector modules and in the combined base model. However, to make the model provide a representative image of global resource conditions additional data and parameters will be required. The resulting global CLEWs model provides a wide range of potential applications and can be easily expanded. As an open source tool it could act as an educational instrument or for policy support and be adapted to different geographical boundaries and detail.