Energy Audits

Whether the goal is to simply reduce energy or actually pursue some level of LEED-EB O&M certification, the first step is to conduct an energy audit, which can take on varying sizes, scopes and yes, price, depending on the desired outcome. A LEED EB O&M prerequisite requires a basic ASHRAE Level I walk-through as prescribed by the procedures for commercial building energy audits manual. This widely recognized approach breaks the energy audit activities down into three levels of effort: 1) Level I walk-through, 2) Level II energy survey and analysis and 3) Level III detailed analysis of capital-intensive modifications. 

An ASHRAE Level I walk-through begins with a preliminary energy-use analysis used to benchmark a building’s energy performance and related cost for each fuel type utilized in the building. The auditor will conduct a brief “walk-through” to document any special problems or needs the facility might have, followed by a space function analysis to develop a rough estimate determining energy use for all significant operations categories. Finally, potential savings are calculated for identified low-cost and no-cost opportunities. These types of opportunities are usually operational changes and maintenance procedures that can result in significant savings. Any capital improvement opportunities are noted for further study, along with an initial estimate of related costs and savings.

An ASHRAE Level II Energy Survey and Engineering Analysis moves beyond a Level I walk-through to include a significant amount of research concerning the mechanical and electrical system design, as well as operating conditions. Key operating parameters such as schedules, water and air temperatures, humidity levels, ventilation quantities and light levels are measured and then compared to design levels. The time taken to conduct these measurements depends largely on whether the information has to be logged manually or electronically. After a breakdown of total annual energy use, all possible energy-saving modifications to equipment and operations are documented along with estimated costs and savings projections.

With energy reductions ranging from 20 to 40 percent, implementation of the energy audit recommendations will generally see a payback period of less than two years. To ensure maximum efficiency on an ongoing basis, some type of commissioning process such as retro-commissioning or Continuous Commissioning®[1]is generally suggested.

And if you aren’t eligible for federal stimulus funding to get started on energy-savings activities, check with your local utilities provider to see if they have a program that follows similar guidelines as the steps described above. Many are subsidizing some or all of the costs associated with either energy audits or existing building commissioning. Or, you could fund these options in your upcoming budget. Don’t look at it as an expense but rather an investment that will quickly pay for itself, ultimately becoming recouped back into your budget.