Abstract: A hydrogen production system includes a hydrogen generation device to generate hydrogen, and a compressor to compress the hydrogen. The hydrogen generation device and the compressor are connected by a first line. The compressor and a hydrogen utilization equipment to utilize the hydrogen compressed by the compressor are connected by a second line. A hydrogen storage unit to store the hydrogen compressed by the compressor is connected to the first line by a first bypass line. The first bypass line has a first control valve to control a flow of the hydrogen in the first bypass line.

Abstract: A hydrogen production system includes: cell stacks to produce hydrogen by electrolyzing water using supplied power; and a control unit. The control unit controls at least one specific cell stack of the cell stacks. The control unit selectively executes a load adjustment control to adjust a voltage or current of the power supplied to the specific cell stack, based on the amount of hydrogen production required for the entirety of the cell stacks, and an ON/OFF control to turn ON or OFF the power supplied to the specific cell stack.

Abstract: A fuel cell system includes a fuel cell, a fuel gas supply line, an oxidizing agent gas supply line, a fuel gas discharge line, and a reformer provided in the fuel gas supply line. A first circulating line circulates the fuel gas from the fuel gas discharge line to an upstream side of the reformer in the fuel gas supply line as a first circulating gas. The circulation device is provided in the fuel gas supply line, and suctions the first circulating gas by using the flow of the fuel gas flowing through the fuel gas supply line as a driving flow. A second circulating line circulates the fuel gas from a downstream side of the circulation device in the fuel gas supply line or the fuel gas discharge line to the upstream side of the circulation device in the fuel gas supply line as a second circulating gas.

Abstract: A fuel cell system includes a fuel cell, a fuel gas supply line, an oxidizing agent gas supply line, a fuel gas discharge line, and a reformer provided in the fuel gas supply line. A first circulating line circulates the fuel gas from the fuel gas discharge line to an upstream side of the reformer in the fuel gas supply line as a first circulating gas. The circulation device is provided in the fuel gas supply line, and suctions the first circulating gas by using the flow of the fuel gas flowing through the fuel gas supply line as a driving flow. A second circulating line circulates the fuel gas from a downstream side of the circulation device in the fuel gas supply line or the fuel gas discharge line to the upstream side of the circulation device in the fuel gas supply line as a second circulating gas.