Description

Typical Applications

A

Partially Measured Retrofit Isolation

Savings are determined by partial field measurements of the energy use of the system(s) to which an ECM was applied. Some, but not all, parameters may be stipulated.

Lighting retrofit where pre- and post-retrofit fixture Wattages are measured. Operating hours of the lights are typically agreed upon.

B

Retrofit Isolation

Savings are determined by field measurement of the energy use of the systems to which the ECM was applied.

Variable speed drive on a pump. Electricity use is measured by a kWh meter installed on the electrical supply to the pump motor.

C

Whole Facility

(Utility Bills)

Savings are determined by measuring energy use at the utility meter level. Bills may be corrected for weather.

Several ECMs affecting many systems in a building. Utility Bills are used.

D

Calibrated
Simulation

Savings are determined using building simulation. This option is rarely used, and is used primarily when there is no pre-retrofit utility data available.

Multifaceted energy management program affecting many systems in a building but where no base-year data are available.