Appliance cycling by Alliant Energey began this week. The electric utility is cycling air conditioners for participating customers in Iowa, meaning that the air conditioners will be cycled in 15-minute intervals to reduce overall energy usage from 1 to 7 p.m. The cycling is done by Alliant Energy sending a signal through a small control switch in the central air unit which turns the unit off and on every 15 minutes while the furnace fan continues to circulate the cooler, drier air already in the home. The cycling occurs May through September on weekdays, but not holidays or weekends.