A significant advantage of the FuelCell Energy carbonate Direct FuelCell® (DFC®) technology is the process of internally reforming the fuel source. The ‘Direct FuelCell’ terminology reflects the ability to provide hydrocarbon fuels such as natural gas or biogas directly into the fuel cell, where the fuel is converted to hydrogen before reacting electrochemically to make power (see How Fuel Cells Work). This means that DFC plants can use readily available fuels rather than being dependent on a hydrogen infrastructure.
FCE is developing a variation of the DFC technology that produces extra hydrogen beyond what is needed for power production, which is then purified and supplied to a local hydrogen user. This technology will transform a distributed power generation system into one which is also a distributed hydrogen production system.
This concept has the potential to help eliminate the infrastructure issue which has impeded the adoption of hydrogen-powered fuel cell vehicles: hydrogen can be produced locally at or near filling stations, along with power and waste heat for thermal applications. This production of power, heat, and hydrogen is called tri-generation, and the presence of three high-value revenue streams gives the concept a tremendous commercial potential.
In addition to hydrogen vehicle filling stations, another market for the technology is distributed hydrogen production for industrial applications, such as metal heat treating or glass manufacturing. FCE is currently fabricating a system for use at a copper processing facility under a U.S. Department of Energy supported field trial program.
FCE’s first field prototype of this technology is operating at the Orange County Wastewater Treatment Plant in Fountain Valley, California. In this project renewable biogas from the wastewater treatment process is converted to ultra-clean power and renewable hydrogen, which is provided to a fuel cell vehicle fueling station at the plant.
These initial field trials use conventional mechanical systems for purifying the hydrogen and compressing it to the level required by the application. FCE is also developing advanced electrochemical technologies that utilize electrochemical cells to purify the hydrogen stream and to compress the hydrogen to high pressures. These electrochemical systems have the potential to reduce the cost and parasitic power requirements of hydrogen purification and compression.