  An increasing number of studies using energy system optimisation models are
conducted with higher spatial and temporal resolution. This comes with a
computational cost which places a limit on the size, complexity, and detail of
the model. In this paper, we explore the relative importance of structural
aspects of energy system models, spatial and temporal resolution, compared to
uncertainties in input parameters such as final energy demand, discount rate
and capital costs. We use global sensitivity analysis to uncover these
interactions for two developing countries, Kenya, and Benin, which still lack
universal access to electricity. We find that temporal resolution has a high
influence on all assessed results parameters, and spatial resolution has a
significant influence on the expansion of distribution lines to the
unelectrified population. The larger overall influence of temporal resolution
indicates that this should be prioritised compared to spatial resolution.
