On: Solar panels disguised as terracotta tiles in Pomp...

[pjc50]

The temperature coefficient of resistance is real, though, and could do with an explanation that isn't too quantum.

[wcrossbow → pjc50]

Of course it is! And the explanation isn't even too quantum. Heat induces atoms to vibrate, these vibrations mess up with the perfectly periodic potential that you would have at 0 K and induces electron scattering which leads to more electrical resistance.