To improve power supply harmonic current and conduction noise while reducing flicker without lowering power consumption of a load.

The power controller controls supply of power from an AC power supply to the load whose resistance characteristic to temperature is positive. By providing a lighting control section including a plurality of half wave sections of supply voltage waveform when starting energizing and when finishing energizing, the power controller performs intermittent energizing such that: the predetermined half wave section out of the lighting control section is set as an energizing section where energizing is performed by zero cross control; and the remaining half wave section is set as a dormant section where energizing is not performed. In one embodiment, where there are a plurality of loads, by providing the same lighting control section including a plurality of half wave sections of supply voltage waveform for the respective loads, the power controller performs the intermittent energizing such the predetermined half wave section out of the lighting control section is set as the energizing section where energizing is performed by zero cross control, and the remaining half wave section is set as the dormant section where energizing is not performed. The energizing sections are provided to differ for every load and not to be superposed on each other in the same lighting control section.