With the sub-freezing temperatures recently, I have hooked up my hummingbird feeder heater, so the hummers have some non-frozen sugar water to drink.
This consists of four parts: a thermostatically controlled outlet, a small waterproof heating pad, paperclips to attach to the feeder, and an extension cord to connect the outlet to the heater.
Here’s the thermo outlet, that switches on the power when the temperature drops below 35°F, and off when above 45°F, so the heater is only on when it’s cold enough to need it:
And the heating pad, originally designed to heat engine blocks, held below the hummingbird feeder by paperclips:
The heating pad gets really hot, enough to keep the sugar water liquid. I use the clips to avoid melting the plastic base of the feeder.
Here’s another angle:
A customer on the feeder:
It’s a bit of a hack, but it works really well.