Intermediate Temperature Solid Oxide Fuel Cell Stack
Centralized power generation systems offer excellent economy of scale but often require long transmission distances between supply and distribution points, leading to efficiency losses throughout the grid. Additionally, it can be challenging to integrate energy from renewable energy sources into centralized systems. Fuel cells—or devices that convert the chemical energy of a fuel source into electrical energy—are optimal for distributed power generation systems, which generate power close to where it is used. Distributed generation systems offer an alternative to the large, centralized power generation facilities or power plants that are currently commonplace. There is also a need for small, modular technologies that convert natural gas to liquid fuels and other products for easier transport. Such processes are currently limited to very large installations with high capital expenses. Today’s fuel cell research generally focuses on technologies that either operate at high temperatures for grid-scale applications or at low temperatures for vehicle technologies. There is a critical need for intermediate-temperature fuel cells that offer low-cost, distributed generation both at the system and device levels.
Project Innovation + Advantages:
United Technologies Research Center (UTRC) is developing an intermediate-temperature fuel cell for residential applications that will combine a building’s heating and power systems into one unit. Existing fuel cell technologies usually focus on operating low temperatures for vehicle technologies or at high temperatures for grid-scale applications. By creating a metal-supported proton conducting fuel cell with a natural gas fuel processor, UTRC could lower the operating system temperatures to under 500 °C. The use of metal offers faster start-up times and the possibility of lower manufacturing costs and additional automation options, while the proton conducting electrolyte offers the potential for higher ionic conductivity at lower temperatures than regular oxygen conducting solid oxide electrolyte materials. An intermediate temperature electrolyte will be used to achieve a lower operating temperature, while a redesigned cell architecture will increase the efficiency and lower the cost of UTRC’s overall system.
If successful, UTRC’s intermediate-temperature fuel cell for residential applications will save energy and emissions by combining the heating and power systems into one unit.
Enabling more efficient use of natural gas for power generation provides a reliable alternative to other fuel sources—a broader fuel portfolio means more energy security.
Natural gas produces roughly half the carbon dioxide emissions of coal, making it an environmentally friendly alternative to existing sources of power generation.
Distributed generation technologies would reduce costs associated with power losses compared to centralized power stations and provide lower operating costs due to peak shaving.