I realize a lot coops on this site have electricity and it is needed when raising chicks.
That being said; I always cringe when I hear of electricity in a chicken coop for heat. It you want to help your birds then put in air conditioning.
Dry bedding, 120 volts, dust, feathers, a flighty or panic stricken bird, water maybe a frayed or improperly protected extension cord.
Totally unnecessary for birds that are cold hearty in most cases and have been raised on this continent for over 100 years with out it.
What could go wrong???
Accidents do happen that is why they put erasers on the ends of pencils.
I live in Canada was subject to -40º last winter.
No heat or light in coop no problems.
I am also aware not everyone will necessarily follow my lead.
My point is execute safe guards do not burn anything down or electrocute yourself and forget about heat in mostly all cases.
Ron MacKinnon