Best Practice Guide

Local Governments

Introduction

Planning an Energy Program

Energy Profiles

Energy Audits

Certification Programs

Assessing Energy Performance

First Steps

Funding and Approval

Education

Lighting

Central HVAC System

Procurement Policy

Building Envelope

Demand Response

Distributed Generation

Water Use

Motors

Food Service

Resources and Appendices

Lessons Learned


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Planning an Energy Program

Energy Audits

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An energy audit first identifies how energy is used in a facility, and then recommends ways to improve energy efficiency and reduce energy costs. In practice, there is wide variance among the different levels of energy audits available. Or, as Albert Thumann writes in the Handbook of Energy Audits, "There is a direct relationship to the cost of the audit (amount of data collected and analyzed) and the number of energy conservation opportunities to be found."

The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) identifies three levels of energy audits:

  • Walk-through Assessment: energy bills are analyzed and, possibly, a brief visual survey of the facility is conducted. The subsequent report identifies no-cost and low-cost opportunities. This is the least costly of the three levels.
  • Energy Survey and Analysis: a more detailed analysis is conducted, including a breakdown of how energy is used within the building. Recommendations consider a city or county's operations and maintenance, constraints, and economic criteria. Potential capital-intensive opportunities are identified in the final report for further research and analysis. This is the typical level of audit.
  • Detailed Analysis of Capital-Intensive Modifications (Investment-Grade Audit): this analysis focuses on capital-intensive opportunities and provides a higher degree of monitoring, data collection, and engineering analysis. The report includes detailed cost and savings information with a high-level of confidence sufficient for major capital investment decisions, and may include a reasonable timeline for implementation of each recommendation.

Local utilities are valuable partners for energy audits. The utilities can arrange for one of their engineers to assist with an energy audit or can recommend third-party providers in your area. The utilities also have testing equipment, such as portable meters and diagnostic software, that in-house facility staff can use to conduct an energy audit. Check with the local water agency, too, to see if they provide water audits - integrating energy-related and water-related upgrades into one action plan provides additional cost savings with the least amount of disruption to workers and building occupants.

Remember that certain problems only occur during a particular time or season. Time energy audits accordingly. For example, if you decide to upgrade chiller equipment that underperforms in warm weather, be sure to schedule the energy audit during summer months so that engineers can test it in the appropriate conditions.


Resources

Flex Your Power information on Audits, Classes, and Services

U.S. Department of Energy, Energy Efficiency and Renewable Energy, Energy Audits: Reading List

Thuman, A., PE, CEM and Younger, W.J., CEM. Handbook of Energy Audits, Sixth Edition. Fairmont Press, 2003.

Pacific Gas and Electric, Energy Audit by Experts.

Pacific Gas and Electric, Pacific Energy Center, Tool Lending Library has thousands of measurement tools available for short-term energy projects like in-house energy audits.

Southern California Edison, Online Energy Survey