The real impact of specific energy improvement or carbon reduction measures is often clouded by the impact of ancillary operational activities and equipment performance, as well as pre-and post retrofit measurement and verification (M&V) methods. Consider to what extent the weather and occupancy contribute to the before and after consumption or emission results, and normalise the data accordingly. Operations and maintenance (O&M) activities changed substantially during Covid, and O&M activities post-Covid may also differ from pre-Covid activities. There may be other factors that impact performance before and after implementation, whether it is the consultants providing support, the measurement devices used, the timing of measurement intervals etc. Establish measuring parameters before the implementation of the ECMs or CRMs to develop more reliable results.