Energy audits

Ten things to know
Friday, June 1, 2012
By Scott Martin

An energy audit is the logical first step in helping to reduce a facility’s utility costs and carbon footprint, and justify capital expenditures.

Here are 10 things every property and facility manager should know before embarking on an energy audit.

1. Proper utility bill analysis
The auditing firm should use software specifically designed for utility bill analysis. It should also adhere to the process defined in ASHRAE guideline 14, Measurement of Energy and Demand Savings.

2. Appropriate building description
An energy audit should provide a detailed description of all energy and water-consuming equipment and systems. It should also include how the equipment is controlled.

3. Schematics of systems
Often, energy audits only look at equipment; they don’t take into account that the equipment is part of a larger system. Without schematics, these audits are missing about 30 per cent of the potential energy savings. Because of this, insist on schematics to ensure all potential energy conservation measures (ECM) are looked at.

4. A solid list of ECMs
It is common for ECMs to be missed by an auditor. Don’t assume the auditing firm has looked at everything and excluded ECMs for technical and financial reasons. Ask for a preliminary list of ECMs for review. All ECMs should show up in the final report even if they aren’t recommended.

5. Accurate ECM savings
Auditing firms can cut corners by performing savings calculations improperly. For example, a firm may estimate the simple payback and back calculate the savings. This method of calculating savings is not only inaccurate, it is unethical. Insist on obtaining a copy of the savings to check the validity.

6. Accurate ECM installation cost
Inexperience auditing firms often underestimate the installation costs for their ECMs. They typically leave out important costs such as engineering, project management, overhead and profit. Insist on a “Class C” estimate. This gives measured quantities based on a preliminary design, not just a rule of thumb guess.

7. Appropriate ECM selection
Firms that delivery energy audits often have a vested interest in the selected ECM. Controls companies are much more apt to recommend a building automation system (BAS). Lighting contractors may recommend the products that they will make the largest profit margins on. Some engineering firms have close ties with boiler suppliers or contractors. It is important to uncover and avoid these potential conflicts of interest.

8. A detailed improvement scope
Each ECM should have a detailed description of what needs to be done. Broad statements such as, “Install T8 lamps and electronic ballasts” aren’t good enough. Specific information is required about, for example, lighting counts, light locations, recommended lamp wattage and recommended ballast type.

9. Life cycle costing analysis
Most energy audits only list the payback for each ECM. This gives an incomplete picture as it ignores any additional costs or savings. By using a life cycle costing analysis and net present value (NPV), the true benefit of the ECM can be seen. This allows property and facility managers to better invest their money in the ECMs with the best NPV, instead of the lowest payback.

10. Inadequate review
Check the final report for errors. If there are a number of them, the report was not properly reviewed.

Scott Martin, P.Eng., is president of Efficiency Engineering Inc. (EEI). Based in Cambridge, Ont., the firm has been conducting energy audits since 1990. To date, it has recommended more than $32 million in utility savings in more than 12,000 facilities.

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