What is Energy Audit?

How reliable is a building energy audit?

• I'm looking for data on the accuracy of the energy savings predicted by a standard building energy audit.

• Answer:

  Building energy audits are like any other service - they depend on the person or firm doing them, and there is a full spectrum of reliability. Track record is very important when choosing and auditor.  Ask for sample audits carried out in the past, and followup with actual savings realized. Assuming you find someone who knows what they are doing, reliability of their predictions will vary depending on the type of savings.  Lighting savings achieved by switching fixtures or changing lighting schedules, or retrofitting to higher efficiency heaters or air conditioning units are often of high accuracy.  More complicated changes such as changes to HVAC schedules and distribution systems, or changing motors to Variable Frequency Drive (VFD) are more difficult to predict with high accuracy, especially if occupants control temperature and humidity in a space.