For a given group of energy conservation measures (ECMs) in a facility, savings evaluations may be carried out for equipment taken in isolation (Option A/B), or at the facility level if a whole building retrofit has occurred (Option C) or, or as a mixture of the Options A, B and C. This will dictate the metering required, whether whole building metering or sub-metering of equipment is applicable. Below is further detail on the Options and the measurements required:
> Option A: Retrofit isolation, key parameters measurement
Savings are determined by measurement of the key parameter(s) which define the energy consumption of ECMs affected systems. Parameters which are not measured are estimated. An example would be a lighting retrofit where power draw is the key parameter measured and lighting operating hours are estimated based on facility schedules and occupant behaviour.
> Option B: Retrofit isolation, all parameters measurement
Savings are determined by field measurement of the energy consumption and/or related independent or proxy variables of the ECM affected system. An example would be solar PV where generated energy is recorded during the report period.
> Option C: Whole Facility
Savings are determined by measuring energy consumption at the whole facility utility meter level. Examples would be a multifaceted energy management programme affecting many systems in a facility.