Reversible SOC System
Our company is developing a reversible SOC (Solid Oxide Cell) system that uses our currently under-development solid oxide cell to achieve hydrogen production through water electrolysis and power generation through fuel cells in a single cell stack. Leveraging our diverse technologies, we aim to contribute to the realization of a decarbonized, hydrogen-recycling society.
What is a reversible SOC system?
This is a type of energy management system that uses a single SOC to switch between “SOEC, which produces hydrogen through water electrolysis,” and “SOFC, which generates electricity through a fuel cell.” By operating in conjunction with renewable energy generation, it stores excess electricity as hydrogen when it is generated and can generate electricity using hydrogen as needed.
Hydrogen production using SOEC (Solid Oxide Electrolysis Cell)
By leveraging the technology developed for oxygen sensors, it is possible to produce hydrogen from electricity and water using SOEC based on ceramics. This enables highly efficient hydrogen production by combining it with waste heat from processes such as methanation.
Hydrogen power generation using SOFC (Solid Oxide Fuel Cell)
A SOFC (Solid Oxide Fuel Cell) is a device that generates electricity from fuels such as hydrogen. While electrolysis of water produces hydrogen and oxygen, the reverse is true: electricity is generated by reacting hydrogen and oxygen.
System features and functions
This system enables two types of operation: "SOEC, which uses electricity to electrolyze water and produce hydrogen," and "SOFC, which produces electricity through the reaction of hydrogen and oxygen." Since neither emits greenhouse gases such as CO₂, it is an essential technology for achieving carbon neutrality. Because it can switch between hydrogen production and power generation in a single stack, the system can be made more compact compared to using SOEC and SOFC side-by-side, offering advantages such as a smaller installation area.
In SOC systems, the cell stack needs to be maintained at a high temperature of around 700°C, and managing this thermal energy greatly affects the system's efficiency. This system is equipped with a small, highly efficient hot module* that can effectively utilize the heat generated internally, and applies our company's long-cultivated technology for controlling the electrochemical properties of cell stacks in high-temperature environments, as well as thermal fluid analysis technology.
*A hot module is a structure composed of a cell stack, heat source, gas piping, and insulation. It is highly efficient in raising the cell stack temperature to around 700°C and maintaining that high temperature.
System Usage Scenarios
By combining solar power generation, which experiences significant seasonal fluctuations in output, with a hydrogen storage system, it becomes possible to adjust seasonal power supply and demand. This is achieved by converting surplus electricity in the summer into hydrogen for storage using SOEC (Solar Electricity Exchange), and supplementing the electricity shortage in winter with SOFC (Solar-Oxygen Fuel Cell) power generation using the hydrogen stored in the summer.
Furthermore, in the event of a power outage due to a disaster, while solar power generation can secure electricity during the day, electricity becomes unavailable during bad weather or at night. The SOC system can generate electricity at any time using stored hydrogen, providing a flexible energy supply day and night, thus also serving as an emergency power source.
Future prospects
Going forward, in addition to improving the SOC system and obtaining operational data, we will conduct awareness campaigns to promote the widespread adoption of SOC systems in society, search for collaborative partners, and aim to commercialize the product.
Through our SOC business, we aim to become an industry leader capable of providing a wide range of cell stacks, hot modules, and systems to our customers, and we are committed to contributing to the creation of a sustainable society.
Original Program
With high gas utilization and energy density, SOFC are used for power generation, producing electricity and heat from hydrogen and other fuels.
A highly efficient and durable steam electrolysis technology used in industrial applications such as steel, chemicals, and e-fuels.
A system that switches between fuel cell and electrolysis cell functions, enabling both power generation and hydrogen production.*SOFC is a product handled by MORIMURA SOFC TECHNOLOGY Co., Ltd. .