A public filing Apple made last month to the Federal Energy Regulatory Commission describes the Maiden data center's proposed fuel cell system. The filing represents Apple's self-certification that the fuel cell project meets the standards of the Public Utility Regulatory Policies Act (PURPA) of 1978 as a "qualifying facility", setting the facility up for incentives that could include the right to require Duke Energy Carolinas to buy its output.
Apple's fuel cell self-certification filing, docketed by FERC as QF12-327, describes the project:
The Facility will consist of 24 fuel cell systems (“Systems”) using a patented solid oxide fuel cell technology to generate electricity. A single fuel cell consists of an anode, a cathode and an electrolyte placed between the two electrodes. As fuel flows in through the anode side and an oxidant comes in over the cathode, a reaction is triggered that causes electrons to move into the fuel cell’s circuit, producing electricity.
Each System consists of thousands of fuel cells stacked together. Multiple stacks are aggregated together into a "power module", and then multiple power modules, along with a common fuel input and electrical output are assembled as a complete system. Each System is approximately the size of a standard parking space and will produce approximately 200 kW of power. The Systems have a modular design that allows the simultaneous use of multiple Systems in order to achieve the desired electric generation output. Each 200 kW (AC) System is comprised of six individual direct current (DC) power-producing modules and one input/output module for fuel intake and electricity output. Each of the six individual DC power producing modules is feeding electricity to the input/output module which converts the DC power into the systems AC power output. The combination of six DC modules and one input/output module comprise a 200 kW (AC) all-electric System. Each System has a net baseload generating capacity of 200 kW (AC). The total generating capacity of the Facility will be approximately 4.8 MW (AC).The "patented solid oxide fuel cell technology to generate electricity" in this description is reported to be Bloom Energy's Bloom box technology.
Tomorrow, a look at the innovative fuel Apple proposes to use to power these fuel cells.