New Energy Capital Invests in Largest U.S. Fuel Cell Project - The New Energy Capital Cleantech Infrastructure Fund (NECCIF) today announced the financial closing of a $23.5 million investment in the largest integrated fuel cell project in the United States.
The article says the fuel cell application would reduce annual CO2 emissions by 25 million pounds while producing 35 million KWh of electrical energy. Looking at FuelCell Energy's website, their fuel cells have an electrical production efficiency of 47%. Their DFC unit which adds a turboexpander to extract energy from the pressure letdown of pipeline gas claims to boost efficiency to the mid-60%. Whether the efficiency is LHV or HHV was not specified.
The FuelCell Energy fuel cells reform methane (from natural gas or biogas) into carbon dioxide and hydrogen and use the hydrogen to produce electricity. The carbon dioxide still goes into the air. If I were to assume the 47% efficiency is based on the methane input, including reformer process energy losses and then to compare this to a Jenbacher 624 two-stage turbocharged engine (which is roughly the same power output) at 46.8% efficiency, then just exactly how is it 25 million pounds of CO2 emissions is avoided?
On a larger scale, new generation gas turbine combined cycle plants have LHV efficiencies over 60%, so I am just not seeing how fuel cell manufacturers can claim to reduce emissions of CO2 compared to them either. Supercritical coal fired plants have HHV efficiencies of 42 to 43%. On a KWh:KWh basis the CO2 emission reductions are not justified.