ASHRAE, the American Society of Heating, Refrigerating and Air-Conditioning Engineers, just published a new edition of Procedures for Commercial Building Audits. Co-authored by our colleague Dick Pearson, P.E. and ASHRAE Fellow, the book contains a wealth of practical information about energy use in commercial buildings.
You can use the reference to help you understand what you get (or should be getting) when you engage a consultant to conduct an energy audit of one of your buildings.
The book defines four levels of effort:
(1) Preliminary Energy-Use Analysis (PEA)–the PEA assembles the basic energy data from monthly energy records, including energy intensity (total annual energy use/sq ft) and energy cost index (total annual energy cost/sq ft). Energy Stewards provides you with the elements of the PEA.
(2) Level 1 Audit “Walk Through Survey”–includes the PEA and a brief-on site survey that identifies no-cost/low cost interventions and a list of capital interventions worth more study.
(3) Level 2 Audit “Energy Survey and Analysis”–looks at specific end uses of energy and presents a comprehensive list of energy efficiency measures and changes to operation and maintenance procedures. It can include a list of capital interventions, with recommendations for additional analysis to refine preliminary cost estimates.
(4) Level 3 Audit “Detailed Analysis of Capital-Intensive Modifications”–just as the name implies, this level is analysis that includes engineering and economic calculations, with detailed cost and savings projections. It often include simulation of energy use under certain conditions.
While Dick Pearson is a national expert on energy audits, he recommends that any building operator can start a process of a “reverse energy audit”–(1) assemble and track the data used in the PEA; (2) begin to adjust the building’s energy systems to use energy more intelligently. The reverse audit can save money and reduce climate impact immediately, with the added benefit that you are better prepared to understand and use the recommendations of a consultant auditor.
There are many sources of ideas for better building operations. A comprehensive checklist is available from the University of Washington Extension here. Your local utility has checklists, too. These are all candidates for action items in your Energy Stewards Action Table.