Heat generation unit power generation hot water supply system combines a solid oxide fuel cell (800-1000°C) with a solid oxide electrolysis cell (600-800°C), which have high operating temperatures, to operate simultaneously. The heat from the heat generation unit (Patent No. 5829325, "Heat generation unit and hot water supply system") generates 700°C. The thermoelectric generation module generates 1kW using the heat, which simultaneously heats the hot water tank and creates hot water.
On startup, it consumes 1.4kW of electricity for a few hours to heat the heating unit up to operating temperature, but once started, it will continue to generate electricity and produce hot water without requiring any external energy.
Heat generation unit power generation hot water supply system is installed in general homes and businesses and used for power generation, hot water supply, and space heating.In addition, the heating unit can be installed in industrial processes where heat is needed, reducing consumption of hydrogen gas and electricity.
The power consumption per day in a typical household is about 10kWh even in households using IH heaters, so heat generation unit power generation hot water supply system generates 24kWh of electricity per day, so the remaining 14kWh is used for charging electric cars or used to sell electricity to.
If every household in Japan were to use the heat generating unit power generating hot water system, it would generate 454.7 billion kWh of electricity per year.The amount of electricity needed to reduce carbon dioxide emissions from Japan's automobiles, railways, subways, aircraft, and ships would be approximately 402.1 billion kWh per year, and this amount of power generation would exceed this.
The main components of a heat generation unit power generation hot water system are: ① heat generation unit, ② thermoelectric power generation module, ③ hot water tank, ④ control device, ⑤ operation display, ⑥ water supply device, ⑦ evaporator, and ⑧ startup heater. These details are as follows:
①The heat generation unit
Although the heat generating unit has not been commercialized, the G20 (external dimensions: 150 mm long x 150 mm wide x 135 mm high) solid oxide fuel cell (SOFC) and solid oxide electrolyzer manufactured by Magnex Co., Ltd. It can be made using Cell (SOEC).
The heat generation unit is made by connecting the hydrogen and oxygen tubes of a solid oxide fuel cell (SOFC) and a solid oxide electrolysis cell (SOEC) together.
The working principle of the heat generating unit is as shown in the following video.
Although the heat generating unit has not been commercialized, the G20 (external dimensions: 150 mm in length x 150 mm in width x 135 mm in height) solid oxide fuel cell (SOFC) and solid oxide electrolyzer manufactured by Magnex Co., Ltd. It can be made using a cell (SOEC).
The specifications of the G20 are a cell size of 11 cm in length, 11 cm in width, and an electrolyte thickness of 3 μm.In addition, the specific heat of yttria-stabilized zirconia (YSZ), which is an electrolyte, is 0.47 kJ / (kg ･ K) and the specific gravity is 6.0 g / cm3.The amount of heat produced by 20 SOFCs and 20 SOECs with this specification, for a total of 40, is 25,480 J in the following calculation.
11 cm x 11 cm x 0.0003 cm x 0.47 (specific heat) x 6 (specific gravity) x 700 ° C x 4.184 ≒ 637J
* 4.184; Convert from cal to J (1cal = 4.184J)
637J x 40 pieces = 25,480J
In other SOFC power generation examples, about 30% of the generated heat is used for reforming.From this example, 30% of 25,480J,or 7,644J, of heat can be used.
②Thermoelectric power generation module
The thermoelectric power generation module uses eight YGPX024 (external dimensions: length 103 mm x width 143 mm x height 2.1 mm) manufactured by Yamaha Corporation.
The thermoelectric generation module is capable of generating 143W at a temperature difference of 385 ° C.
The high temperature side is the side of the heating unit, and the low temperature side is automatically set to a position that maintains a temperature difference of 385°C between the side and the cooling water heat exchanger.Eight of these are used, which results in a power generation of 1,143W.A supplementary power of 138W is required to account for the loss of 19% from solid oxide fuel cell (SOFC) power generation and solid oxide electrolysis cell (SOEC) electrolysis, and the remaining approximately 1kW can be used as power consumption for indoor electrical appliances. increase.
③Hot water tank
The hot water tank has a capacity of 150 liters, and the water in the tank is heated by pipes through which water from a heat exchanger for cooling water flows to maintain the temperature difference of the thermoelectric power generation modules.
④Control device
The control device controls the heating of the startup heater at start-up, stops heating of the startup heater after start-up and replaces it with a thermoelectric power generation module, manages the power generation status of the solid oxide fuel cell (SOFC) and the electrolysis state of the solid oxide electrolysis cell (SOEC), and maintains normal operation of the thermoelectric power generation unit.It also controls the water supply of the water supply device.
It controls the power supply stop when the system is shut down. Controls the exchange of the thermoelectric generation module to the startup heater.
⑤Operation indicator
The operation display displays the operating status of the solid oxide fuel cell (SOFC), solid oxide electrolytic cell (SOEC), startup heater, and water supply device.
⑥water supply device
The water supply device is a device that sends water to the evaporator in order to supply water vapor to the solid oxide electrolysis cell (SOEC) when the heat generation unit is started up and in operation. The water supply is automatically controlled by the control device.
⑦Evaporator
An evaporator is a device for evaporating water, and the water vapor produced is sent to the tubes that carry hydrogen in the heat generation unit.
⑧Start-up heater
The startup heater is used to heat the entire heat generating unit up to about 700°C, the operating temperature of the solid oxide fuel cell (SOFC) and solid oxide electrolysis cell (SOEC). It has a capacity of 1.4kW and takes several hours to heat up. It stops after the heat generating unit starts operating.
"Quote":URL of copyrighted work
"Magnex Corporation SOFC/SOEC Stack"
https://www.magnex.co.jp/stack.html
"Yamaha Corporation YGPX024"
https://www.yamaha.com/ja/news_release/2021/21030401/