Technologia – Fuel Cell Poland

Molten Carbonate Fuel Cells (MCFC) are high-temperature fuel cells operating at temperatures of 600–700 °C. Like other fuel cells, they use the chemical energy contained in fuels such as hydrogen and convert it directly into electrical energy. What sets MCFC apart from other fuel cells is:

The highest thermodynamic efficiencies, reaching up to 60%
Efficient operation in a cogeneration system with efficiencies of up to 90%
The ability to be used in systems combined with a steam turbine or industrial processes
Fuel reforming can take place inside the cell, which increases efficiency when using fuels other than hydrogen.
The ability to use MCFC technology for carbon dioxide capture from flue gases generated by industrial processes (e.g., conventional power plants, internal combustion engines, cement plants).
The ability for the same device to operate in either fuel cell or electrolyser mode (for use in energy storage processes – "power-to-gas" or "power-to-liquid").

A molten carbonate fuel cell consists of a cathode made of a nickel alloy with other metals and an anode made of nickel oxide, separated by a membrane containing the electrolyte, which is most commonly a mixture of carbonates. Individual cells are connected in series into so-called stacks, which enables easy system scalability.

Once the cell is heated to its operating temperature and loaded, recombination into a carbonate ion occurs at the anode. This ion is passed through the membrane, where it reacts with hydrogen, reducing to carbon dioxide. The hydrogen is oxidized to water vapor, and the excess electrons return through the load, generating electrical energy.

Energy generation

Fuel cells in MCFC technology are an innovative technology in the field of power generation. By using them, conversion efficiencies of up to 67% can be achieved with zero emissions. Furthermore, MCFC cells can operate in combined heat and power (CHP) cogeneration systems, or even trigeneration systems, where a single device would produce electricity, heat, and cooling.

Microgeneration

Thanks to their modularity, an MCFC fuel cell installation can be tailored to the individual needs of the customer. It can serve as a complementary energy source for prosumer use or generate electricity for the grid.

Energy storage

Fuel cells in MCFC technology are inherently reversible devices. After minor modifications to the system, they can also operate as electrolysers. This feature allows for the storage of electrical energy in the form of hydrogen or methane, in combination with a Sabatier reactor, and then the production of electricity during periods of peak demand.

Hydrogen based economy

Hydrogen produced by MCFC electrolyzers has much greater potential than just generating electricity and heat. In a hydrogen-based economy, it can be used to power electric vehicles, produce biofuels in carbon capture mode, manufacture ammonia and fertilizers, and also for metal processing.

Power to gas

MCFC fuel cells, which can also serve as electrolyzers, are an important element of the innovative power-to-gas approach. According to this concept, surplus energy from renewables could be stored in the form of hydrogen or further processed into synthetic methane. These gases could then be transmitted or stored while waiting for peak energy demand.

Power to liquid

Fuel cells can also be an important component of technologies grouped under the name power-to-liquid. Hydrogen produced from surplus renewable electricity could be subjected to the Fischer-Tropsch synthesis process using carbon dioxide captured from the atmosphere or from conventional power plants, in order to produce synthetic biofuels and close the CO2 loop in the economy.