Technical report on the development of amendment 2 to UN GTR No. 21. The report describes the procedural background of the Informal Working Group on Electric Vehicle and the Environment (EVE), established in June 2012, and its subsequent work to develop a standalone UN GTR for determining electrified vehicle power. The report outlines revisions approved during 2022 and 2023, including deletion of Annex 3 reserved for a candidate method, addition of a family concept, definition of an additional TP1 method employing onboard signal distribution ratio, allowance of system bench testing for vehicles too powerful for chassis dynamometer testing, and adjustments to soak area temperature specifications, instrumentation requirements, and calculation tolerances.