The document defines an energy audit as an inspection and analysis of a building, process, or system's energy usage to identify opportunities to reduce energy input without negatively impacting output. The goal of an energy audit is to minimize energy costs and waste through a systematic process. Energy audits can be preliminary, providing a quick overview, or detailed, involving advanced measurements and simulations to precisely evaluate potential energy retrofits.

1. “The judicious and
effective use of energy to
maximize profits (minimize
costs) and enhance
competitive positions”
“The strategy of adjusting
and optimizing energy,
using systems and
procedures so as to reduce
energy requirements per
unit of output while
holding constant or
reducing total costs of
producing the output from
these systems”

2. DEFINITION
 An energy audit is an inspection, survey and
analysis of energy flows for energy conservation
in a building, process or system to reduce the
amount of energy input into the system without
negatively affecting the output(s).
 Energy Audit is the key to a systematic
approach for decision-making in the area of
energy management.

3. OBJECTIVE
 The objective of Energy Conservation is to achieve
and maintain optimum energy procurement and
utilization, throughout the organization.
 To minimize energy costs / waste without affecting
production & quality.
 To minimize environmental effects.

4. PRINCIPLE
 When the object of study is an occupied building
then reducing energy consumption while
maintaining or improving human comfort, health
and safety are of primary concern.
 Beyond simply identifying the sources of energy
use, an energy audit seeks to prioritize the
energy uses according to the greatest to least
cost effective opportunities for energy savings.

5. TYPES OF ENERGY AUDIT
The type of Energy Audit to be performed depends on
- Function and type of industry
- Depth to which final audit is needed, and
- Potential and magnitude of cost reduction desired
Thus Energy Audit can be classified into the following
two types.
i) Preliminary Audit
ii) Detailed Audit

6. Preliminary energy audit is a relatively quick exercise to:
 Establish energy consumption in the organization.
 Estimate the scope for saving.
 Identify immediate (especially no-/low-cost)
improvements/ savings.
 Set a ‘reference point’.

7.  DETAILED ENERGY AUDIT:
 This type of audit offers the most accurate estimate of energy
savings and cost.
 It considers the interactive effects of all projects, accounts for
the energy use of all major equipment, and includes detailed
energy cost saving calculations and project cost.

8. PROCESS

9. LEVELS OF ANALYSIS
 Level 0 – Benchmarking: This first analysis consists
in a preliminary Whole Building Energy Use
(WBEU) analysis based on the analysis of the
historic utility use and costs and the comparison of
the performances of the buildings to those of similar
buildings.
 Level I – Walk-through audit. This inspection is
based on visual verifications, study of installed
equipment and operating data and detailed analysis
of recorded energy consumption collected during
the benchmarking phase;

10.  Level II – Detailed/General energy audit:. This
level of analysis can involve advanced on-site
measurements and sophisticated computer
based simulation tools to evaluate precisely the
selected energy retrofits;
 Level III – Investment-Grade audit: Detailed
Analysis of Capital-Intensive Modifications
focusing rigorous engineering study.

11. GENERAL AUDIT
 The general audit (alternatively called a mini-
audit, site energy audit or detailed energy audit
or complete site energy audit) expands on the
preliminary audit described above by collecting
more detailed information about facility
operation and by performing a more detailed
evaluation of energy conservation measures

12. POLLUTION AUDITS
 With increases in carbon dioxide emissions or
other greenhouse gases, pollution audits are
now a prominent factor in most energy audits.
Implementing energy efficient technologies help
prevent utility generated pollution.
 Online pollution and emission calculators can
help approximate the emissions of other
prominent air pollutants in addition to carbon
dioxide.