In the regulation of heating, ventilation, and air conditioning (HVAC) for a peak cut or peak leveling control of electric power consumption, the amenity of the living environment should be considered. In the existing method, the metabolic equivalent (MET) value is not considered because of the substantial measurement costs and because a special infrastructure is required for both measuring the value by the MET meter and for communicating with the HVAC control server in the home energy management system (HEMS) or building EMS (BEMS). This paper proposes a method for measuring the MET value on a mobile device for accurately calculating the predicted mean vote (PMV). This method is designed as an iPod touch or iPhone application. The application has sufficiently reduced energy consumption for use as a mobile device application and is sufficiently accurate for use as an HVAC control. The availability and usefulness of both the designed application and the proposed MET measuring method is experimentally confirmed, and the reduction in energy consumption is estimated using an actual HEMS.