An energy audit is the key to a systematic approach to decision-making in the area of energy management. The primary function of an energy audit is to identify all of the energy streams in a facility in order to balance total energy input with energy use. The four main objectives of an energy audit are as follows:
To establish an energy consumption baseline
To quantify energy usage according to its discrete functions
To benchmark with similar facilities under similar weather conditions
To identify existing energy cost reduction opportunities
Energy audits vary in depth, depending on the potential at a specific site for energy and cost reductions and the project parameters set by the client. As per ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) standards, there are three types of audits, outlined below.
ASHRAE Level 1 – Walk-Through Analysis/Preliminary Audit
The Level 1 audit alternatively is called a simple audit, screening audit or walk-through audit and is the most basic. It involves minimal interviews with site operating personnel, a brief review of facility utility bills and other operating data, and a walk-through of the facility, all geared toward the identification of glaring areas of energy waste or inefficiency. The data compiled is then used for the preliminary energy use analysis and a report detailing low-cost/no-cost measures and potential capital improvements for further study. Typically, a Level 1 audit will only uncover major problem areas. Corrective measures are briefly described, and quick estimates of implementation costs, potential operating cost savings, and simple payback periods are provided. This level of detail, while not sufficient for reaching a final decision on implementing proposed measures, is adequate to prioritize energy efficiency projects and to assess the need for a more detailed audit.