First electrical power meters (71, 72) measure electrical power supplied from a commercial power system to a residence. A second electrical power meter (73) measures electrical power generated by a distributed power source. Third power meters (74 to 84) measure electrical power supplied to each of a plurality of electric devices. A auxiliary memory (103) stores the power measurement results. An inputter (104) is used for selecting an object included in an image displayed by a display part (105). Each time a user uses the inputter (104) to select an object included in the image, the controller (101) changes the image displayed by the display part (105) to a new image in accordance with the selected object.