> When I mention solar panels near motorways I'm not picturing them right next to the road, I'm thinking of larger strips, perhaps 30-100 meters from the road and in areas that have already become unattractive due to noise pollution. There are many such areas.

FWIW, most of the bigger solarfarms in East Germany seem to be on former Cold War airbases, or in former lignite mining areas. IMHO a pretty good 'land recycling strategy':

https://www.google.com/maps/@51.1658488,12.4325343,5059m/dat...

https://www.google.com/maps/@52.8290328,13.6890243,2783m/dat...

https://www.google.com/maps/@51.3296415,12.6590003,1983m/dat...

https://www.google.com/maps/@52.633346,13.7674599,1989m/data...

https://www.google.com/maps/@53.9209948,13.2235344,3356m/dat...

https://www.google.com/maps/@51.5524298,13.9695021,4648m/dat...

https://www.google.com/maps/@52.612948,14.2381122,2691m/data...