First and second conductive members having different Seebeck coefficients are formed on an insulating substrate. The first and second conductive members are connected by ohmic contact, and the surfaces connected by ohmic contact are covered with a material sheet having a superior heat conductivity and an electric insulating property in the junction surface, such as an aluminum sheet formed with surfaces provided with electric insulating property by alumite treatment or the like. On the opposite side, bonding wires are connected with the first and second conductive members by ohmic contact. The bonding wires are insulated from one another, and used as output terminals of an integrated parallel Peltier Seebeck element chip. The thus produced integrated parallel Peltier Seebeck element chips are connected by one or more serial or parallel cables, to form energy conversion apparatus from electricity to heat and thermal energy transfer apparatus.