After transitioning production from its five-year stack design to its seven-year stack design in the fourth quarter of fiscal year 2018, FuelCell Energy has today provided an update on these modules.
The transition followed an innovation effort focusing on improving the stability of the core cell components as well as improving overall stack and stack module designs.
The seven-year carbonate fuel cell stack life improvement was achieved with less than 5% increase in the cost of the stack module, FuelCell Energy said.
The life extension effort was a key focus of the company’s Internal R&D efforts delivering on the transition.
The effort was also partially supported by the US Department of Energy through the Smart Matrix programme funded by the office of Energy Efficiency and Renewable Energy.
The programme included extensive design verification with accelerated testing of cell components, cells and stacks in the company’s Danbury, CT laboratory facilities.
One year prior to the production transition, a prototype four-stack module was manufactured and placed in operation at a customer site as part of the design verification program.
The stable performance of the stacks in that module – along with the successful completion of various cell and stack test milestones – verified that transitioning to the new seven-year design was a go for the company.
“As of this update, that first prototype module has been operating for two years, and the first modules built after the production transition to the seven-year design have been operating for one year,” FuelCell Energy said in a statement.
“Monitored parameters such as cell voltages and temperatures are trending according to seven-year life expectations.”
“This extension of stack life is extremely significant in terms of power plant operating costs.
“Module restack costs make up approximately half of power plant non-fuel operating cost.”
“At 90% capacity factor, a 1.4MW stack module with five-year life will deliver 55.2 GWh of energy before stack replacement is needed, while a seven-year module will deliver 77.3 GWh, or 40% more energy, for nearly the same capital cost – a module lifetime output unmatched in the fuel cell industry.”
“The life extension effectively reduces the stack replacement component of operating cost by approximately 40%.”