As an alumnus of the MSc Energy Systems course I highly recommend you avoid it at all costs and go to Cambridge or Imperial instead. The director is psychopathic with workloads (60-80 hour weeks, with no breaks over Christmas and Easter), much of the systems approach stuff and shiny industrial partner claims in the handbook are untrue, and it does not seem to have improved at all from what the current cohort are saying - aside from moving to an industrial estate on the edge of Oxford for teaching.