Several factors go into determining why customers’ utility bills may be higher during the summer. The No. 1 cause of higher bills is the extreme heat, Morgan City Utilities Director Bill Cefalu said. Most people run their air conditioner units regularly in the summer, and thus use more electricity. If customers want lower summer utility bills, they should start by setting the thermostat higher when they leave their home or business, Cefalu said. To save on utility costs, the thermostat should be set at no more than 15 degrees lower than the outside temperature. Turning off the air conditioning unit ...