A modelling framework for the simulation of stormwater runoff in ground-mounted photovoltaic solar parks is proposed. Elements in the solar park and their mutual interactions during precipitation events are conceptualized in EPA-SWMM. We demonstrate the potential of the framework by exploring how different factors influence runoff formation. Specifically, we carry out simulations for different sizes of the installation, soil types and input hyetographs. We also show the effect of ground cover, by changing the surface roughness. Outflow discharge from the park is compared to that from a reference catchment to evaluate variations of peak flow and runoff volume. Results highlight no practical changes in runoff in the short term after installation. However, in the long term, modifications in soil cover may lead to some potential increase of runoff. For instance, increments of the peak flow from the solar park up to 21% and 35% are obtained for roughness coefficient reductions of 10% and 20%, respectively. The proposed modelling approach can be beneficial for studying hydrological impacts of solar parks and thus for planning measures for their mitigation.