small battery powered coop heater?

[Chicken.Lytle]

What about one of those heat packs, the type used for shipping chicks, as an emergency heat source?

 

[Vanessabuffsnsilkies]

I don't heat the coop where the adults are because if they get too used to it and there's some kind of power outage then there could be problems.

I do have a 150 watt ceramic heat bulb in with my 3.5 month old silkies. That is on right now... it got down to 1 degree here last night, maybe even below zero. I understand the risk, but they are still kind of young.