Recently，the plant factory attracts grate attention in order to achieve the reproduction of agriculture. However，a large amount of power for the air conditioner and LED lighting is required for the plant factory. Therefore，the procurement method of power energy is an issue in order to spread the plant factory. In order to solve this problem，the authors studied the hybrid energy supply system named“eco mori”combining photovoltaic generation (PV) and air conditioner. In this paper, the DC power supply system for providing PV output more efficiently is proposed by “eco mori”.Validity and effectiveness of the DC power supply systems is ascertained for the power supply test used actual equipment. Moreover，valid criteria for the DC power supply is discussed.