This part of IEC 62282 covers operational and environmental aspects of the stationary fuel cell power systems performance. The test methods apply as follows: power output under specified operating and transient conditions; electrical and heat recovery efficiency under specified operating conditions; environmental characteristics; for example, exhaust gas emissions, noise, etc. under specified operating and transient conditions. This document applies to all kinds of stationary fuel cell technologies, such as: alkaline fuel cells (AFC); phosphoric acid fuel cells (PAFC); polymer electrolyte fuel cells (PEFC); molten carbonate fuel cells (MCFC); solid oxide fuel cells (SOFC). This standard does not provide coverage for electromagnetic compatibility (EMC). This standard does not apply to small stationary fuel cell power systems with rated electric power output of less than 10 kW which are dealt with IEC 62282-3-201. Fuel cell power systems may have different subsystems depending upon types of fuel cell and applications, and they have different streams of material and energy into and out of them. However, a common system diagram and boundary has been defined for evaluation of the fuel cell power system (see Figure 1). The following conditions are considered in order to determine the system boundary of the fuel cell power system: all energy recovery systems are included within the system boundary; all kinds of electric energy storage devices are considered outside the system boundary; calculation of the heating value of the input fuel (such as natural gas, propane gas and pure hydrogen gas, etc.) is based on the conditions of the fuel at the boundary of the fuel cell power system. The standard does not provide safety requirements for the testing of stationary fuel cell power systems. Safe conduct of the performance tests shall be ensured by following the local safety regulations and the manufacturers instructions.