Abstract: The present disclosure provides a thermostat applied to a heating, ventilation and air conditioning (HVAC) system including: a memory storing machine executable instructions; one or more processors, wherein when the machine executable instructions are executed, the one or more processors are configured to perform the following operations: obtaining device information of the HVAC system, and region information of a user's location; according to the device information of the HVAC system and the region information, in response to an energy saving mode and a schedule selected by the user, determining a predicted energy consumption and a reference energy consumption; and determining energy saving amount according to the predicted energy consumption and the reference energy consumption.