A system for load control in an electrical power system is described, wherein one or more temperature-monitoring devices are provided to control operation of a pool pump. When ambient temperatures are relatively high, and thus, electrical power demands from air conditioning systems are relatively high, the temperature-monitoring devices can remove power from the controlled device during the hottest portions of the day. The temperature-monitoring devices can provide power to the controlled devices during the cooler portions of the day. During heat waves or other periods of relatively continuous high heat, the temperature-monitoring devices can schedule power to the controlled devices to reduce overall power demands and to run the controlled devices during the cooler portions of the day when air conditioning electrical loads are reduced. The temperature-monitoring devices can also coordinate operation of the pool pump and a pool heater.