Energy consumption in residential sector has been increasing year by year since 1965. To improve this situation, it is necessary to reconsider the traditional energy supply systems. Distributed power source systems, such as photovoltaic (PV) system and micro co-generation system, are considered as solutions to current residential energy problems. In order to utilize these systems effectively, understanding detailed energy consumption of residences is required. The purpose of this research is to clarify detailed energy consumption; seasonal and annual energy consumption classified by uses, the effect of energy-saving apparatus and heating demand of residences located in the north of Kyushu, Japan. Major results are as follows: (1) energy consumption for hot water supply is larger than ones for lighting, air-conditioning and cooking among most houses, in the north part of Kyushu, (2) PV system is quite effective to save energy of residential buildings, and (3) Heat demand and electric power demand of residences are clarified by detailed measurement for installing individual dispersed power source system, some houses show high thermoelectricity ratio enough to move micro co-generation system effectively, even at present. (c) 2006 Elsevier B.V. All rights reserved.