Fuel cells are electrochemical devices that use chemical energy from hydrogen or other fuel sources to cleanly and efficiently produce electricity. They have a wide range of applications including transportation, industrial, commercial, residential, and long-term energy grid storage. As the energy market further prioritizes lower emission and cleaner systems, conventional fossil-based combustion technologies far underperform outputs as compared to fuel cells. Because fuel cells can use hydrogen as the starting energy input, they can operate at higher efficiencies, emit zero emissions, produce no air pollutants, and function rather silently due to the reduced number of moving internal parts.

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US Department of Energy, NREL