Continuous power is the power that systems are designed to run on indefinitely, while peak power is the power that systems are designed to support for brief periods. Continuous power is what engines and other propulsion systems run at the majority of the time.
GM's previous industry-best fuel cell stack — Stack 2000 — has a power density of 1.6 kW per liter and weighs in at 190 pounds. Stack 2000's continuous power output is 94 kW (126 hp) with a peak power output of 129 kW. As a point of comparison, Ballard's top stack has been quoted at 75 kW of continuous power.
As with Stack 2000, the membrane at the core of each cell in the new stack does not need external moisture to maintain its efficiency. This is accomplished with a unique and proprietary method of water management inside the stack. Fuel cells need humidification to properly function.
The new stack continues to have Stack 2000's excellent cold start performance: full power in 30 seconds at minus 20 degrees Celsius (minus 4 degrees Fahrenheit). This cold-start performance is critical in colder climates. Despite the ability to start quickly in extreme cold, GM engineers continue to improve the stack's cold weather capabilities.
