Assuming that "clean" really means "low carbon", then only majority nuclear/hydro/geothermal electricity grids can currently achieve that. Wind/solar on the other hand are intermittent, and always need to be complemented with "dispatchable" energy sources to handle the base load.
That can either be hydro/geothermal if you were blessed with the right geography (like Iceland or Sweden), nuclear if you weren't but are pragmatic about it (like France), or coal/gas if you got scared of nuclear but still have a large country to power (like Germany).
I'm stressing the latter because, even as Germany is rightfully praised as a renewables champion that invested billions to be 70% wind/solar powered on a very good day, that's all in vain when it comes to climate change : coal/gas is so bad that their average carbon intensity of electricity production is still mediocre (see http://electricitymap.org/)
So, renewables doesn't always mean low carbon. If that's the primary concern for the location, France is probably their best bet (nearly as low carbon intensity as Iceland, and much closer to the UK)