What Is a Commercial Building Energy Audit?

The first step towards making your commercial building more efficient is an energy audit.

Although most people are already aware of the basic concept of a commercial building energy audit, not everyone knows what the actual process is. Of course, everyone knows that there is a need for an assessment of the energy efficiency of a commercial building, but the benefits of conducting it may not be immediately clear. The question is then how to put all the data received from an energy audit into practical use to get the maximum benefits.

The original objective of conducting an energy audit on a commercial building is to identify the available energy-saving opportunities. Other important reasons for an energy audit include increasing asset value, lowering ownership costs & promoting environmental stewardship, human comfort and health and safety.

When conducting an energy audit on a commercial building, the attention is often focused on the energy consumption data as well as the structures consuming the energy. With a proper energy audit, you will be able to identify economically responsible systems and sustainable energy efficiency measures that can help reduce energy usage and carbon emissions.  

The Workings of a Commercial Building Energy Audit

In order to effectively conduct a comprehensive energy audit on a commercial building, you need to examine all of the major factors affecting energy consumption. Here is how it is done:

1. An analysis of the utility bill based on the historical data given by clients:
2. A quick review of the utility service feeds (electric and gas meters)
3. A quick review of the areas and processes each utility service feed served
4. A spreadsheet analysis of the utility data with the corresponding charts
5. Identifying the average load factors
6. A quick review of the billing rate schedules
7. An on-site survey of the property
8. Collate nameplate data and get the efficiency information for all energy using systems and equipment. These may include but are not limited to the following:
9. Lighting systems
10. Space heating and cooling

• Other power-using systems like exhaust fans and domestic hot water

1. Plug/industrial/process loads
2. Building envelope
3. Collate data and calculate equipment performance and runtime
4. Using available building management system and/or data loggers to collate building operating and equipment data
5. Ascertaining that the temperature, pressure, flow, and humidity sensors are properly calibrated

• Collate electric power and thermal consumption data

1. Do an analysis of trend data and curve-fit to determine actual performance curve
2. Review the as-built construction drawings if available
3. Review the condition of the building envelope
4. Conduct interviews with facility managers and other facility staff to:
5. Ascertain current hours of operation
6. Ascertain areas of concern and areas of opportunity
7. Study current controls and operating schedules.
8. Diagnostic testing, including:
9. Insulation Installation Inspection
10. Smoke Pencil and Infrared Camera Testing of Building Envelope Sealing
11. Refrigerant Charge
12. Central DHW/Hydronic Heating Systems
13. Centralized Ventillation Systems
14. Exhaust Fan Flow Measurements
15. Duct Leakage
16. Cooling Coil Airflow Testing
17. Air Handler Fan Watt Draw
18. Equipment kW and kWh draw
19. Combustion Efficiency & CO Testing