Live Electricity Grid
The page, including its method of retrieving and displaying data, is used as part of a year 2 undergraduate Energy Resources module at the University of Reading, which I convene and teach.
The renewables category is taken to include wind, solar, hydro (inc. pumped storage) and biomass. Nuclear is also considered a low carbon form of electricity generation.
For data on changing fuel mix used in electricity generation, please see my page on this here.