Heated waterers supply warm water for outdoor pets or farm animals and are typically used in climates where temperatures drop below freezing. They usually use an electric heating element, and have some thermostatic control that turns the heater off when the ambient temperature is warm.
One common application for chicken waterers is in chicken coupes in northeast climates. These devices reduce the frequency that the owner has to visit the chickens to refill the waterer. Options with varying capacities are available. Some waterers hold as little as 1 gallon, but modern waterers hold capacities up to 5 gallons, further reducing the frequency with which the owner has to refill the tank.