IEC 62282-3-200:2015 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 new edition includes the following significant technical changes with respect to the previous edition: a stabilization zone of +- 10 % for thermal output of 100 % response time is provided instead of the tests for thermal output of 90 % response time, while the tests for electric output of 90 % response time remain as an option; the calculations for the ramp rate in kW/s are deleted and only the calculations for the response time (s) remain.