DISPLAY DEVICE, DISPLAY METHOD, AND COMPUTER PROGRAM

PROBLEM TO BE SOLVED: To provide a display device capable of switching a graph of a generated amount of power, etc., from yearly display to monthly display and to daily display by a simplified visual and sensuous operation.SOLUTION: The display device comprises: a receiving unit for receiving information indicating generated power, etc., transmitted from a photovoltaic power generation system for generating power by sunlight and selling/buying power in cooperation with a commercial AC system; a yearly amount of power calculation unit, a monthly amount of power calculation unit, and a daily amount of power calculation unit for calculating the generated amount of power, etc., in each year, each month, and each day; a first graph display unit for displaying a graph indicating the amount of power in each year; a first operation detection unit for detecting an operation in a prescribed area in the graph corresponding to each year; a second graph display unit for displaying a graph indicating the generated amount of power, etc., in each month of the year corresponding to the prescribed area operated; a second operation detection unit for detecting an operation in a prescribed area in the graph corresponding to each month; and a third graph display unit for displaying a graph indicating the generated amount of power in each day of the month corresponding to the prescribed area operated.