Abstract: A building energy storage and conversion apparatus includes at least a control unit, an electric power conversion unit, an energy conversion unit and a thermoelectric conversion unit to regulate energy sources of the electric power conversion unit. The energy conversion unit generates cold/heat energy which is stored through a heat storage equipment (for cold/heat energy). The cold/heat energy can be released when needed. When the cold/heat energy is in a surplus state, it can be converted to electric power through the thermoelectric conversion unit or stored in the form of electric power. Thus energy resources can be converted and utilized in an optimal fashion to achieve energy self-sufficiency of a building. Moreover, energy exchange with other buildings in the neighborhood can be done to balance demand and supply.