The collection of empirical data to determine building energy performance is an important but complex and costly activity. Careful development of energy monitoring projects can make a crucial difference in the value of project results relative to the expense.

Increasing the widespread understanding of how energy is used and the types of services it provides in commercial, institutional, and related (light industrial, large multifamily, and mixed commercial/residential) buildings has proved to be difficult. This difficulty arises from the following variables: the complexity of buildings as energy systems; the diversity of sizes, uses, schedules, and types of buildings; the changes in uses of buildings; and the mixture of uses within individual buildings. These factors make building energy performance and energy (and dollar) savings from energy improvements difficult to categorize and compare.

The audience for this guide is diverse, including energy suppliers such as utilities, building owners and managers, building occupants, designers, public and private research organizations, equipment manufacturers, and public regulators.

The user of this guide must be familiar with the fundamental techniques of engineering project management and energy performance data collection, data management, and data analysis. See Refs (1-4)³ for a discussion of techniques related to the collection and analysis of energy performance data.