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IMA Energy & Environment Blog

Take Building Performance to the Next Level

Key Points

  • An energy audit identifies cost-saving measures and forms the basis of an energy management plan.
  • ASHRAE defines three levels of audits, ranging from a simple walk-through to a detailed analysis.
  • Audits are performed by consultants, engineering firms, and energy service companies (ESCOs).
  • Ameren Illinois offers FREE Level 1 energy audit walkthroughs.

In the U.S., commercial facilities spend more than $170 billion a year on utilities, making energy a cost worth managing. Whether you are looking for simple efficiency upgrades or developing a long-term improvement strategy, an energy audit is the first step in reducing energy use and saving money. It can help you identify efficiency measures, analyze their cost and savings potential, and lay the groundwork for an energy management plan.

Types of energy audits

An audit can range from a simple assessment to a detailed evaluation including diagnostic testing and data tracking. The American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) defines three levels of energy audits.

Level 1 Walk-through. A Level 1 audit is the basic starting point for optimizing building energy performance. It consists of an analysis of utility bills and a brief on-site inspection of the facility and its systems. The main objective of a Level 1 assessment is to identify low-cost, energy-saving measures and develop an initial list of more capital-intensive improvements.

Level 2 Energy survey and analysis. Level 2 audits provide in-depth assessments of building energy use and more detailed cost and savings analyses of recommended energy efficiency measures. Energy performance is benchmarked against similar facilities and energy use is broken down by end use, such as lighting and air conditioning. Key staff members are interviewed to gain a thorough understanding of building characteristics and operations. A detailed site assessment may include a variety of diagnostic testing, such as:

  • Combustion analysis
  • Light level assessment
  • Air and water flow measurement
  • Leakage and insulation assessment using infrared thermography

Level 3 Detailed survey and analysis. A Level 3 audit provides detailed recommendations and financial analysis for major capital-intensive efficiency upgrades. In addition to Level 1 and Level 2 procedures, the Level 3 audit may include capturing long-term energy use data through data-logging devices or through the building’s energy management system.

Which type is right for your facility?

For smaller facilities with no plans or budget for major energy efficiency investments, a Level 1 audit will identify the best low-cost, energy-saving opportunities that can yield immediate results. Level 2 and Level 3 audits are appropriate for larger, more complex facilities with defined energy efficiency goals. Although they are more time-consuming and expensive, these audits provide the in-depth evaluation and financial analysis needed for major equipment upgrades and long-term investments. Work with your service provider to select the right type of audit for your needs.

Finding an energy auditor

Energy auditing services are offered by energy consultants and engineering firms, as well as energy services companies (ESCOs). ESCOs not only identify efficiency improvements, they also provide financing and installation services. Depending on the size of the facility and the scope of the audit, the process may involve a single individual or a team of specialists.

Professional certification will help to ensure that the service provider is trained in the auditing process. Certifying organizations include ASHRAE and the Association of Energy Engineers (AEE). Some Ameren Illinois Program Allies are certified in energy auditing services and can help you with any level of building energy audit.

To locate an ESCO in your area, go to the National Association of Energy Service Companies’ provider search. The U.S. Department of Energy’s Industrial Assessment Center provides no-cost energy audits for qualifying manufacturing facilities.

Ameren Illinois offers FREE Level 1 energy audits

Through the Ameren Illinois Energy Efficiency Program, you can get a FREE Level 1 energy audit with an Ameren Illinois Energy Advisor. Scheduling a building walkthrough with an Ameren Illinois Energy Advisor is a great first step in making your building as efficient as it can be. During the walkthrough, you can learn about low- and no-cost ways to reduce your energy use and available cash incentives, and discuss any equipment upgrades you are considering. Call 866-800-0747 to schedule a walkthrough with an Energy Advisor or visit to learn more about our program and its available incentives.