Anatomy of the Energy Audit

by John A. Herbert

An energy audit is much like an annual financial review but instead of profit and loss, the data and information is based on historical energy usage, the energy audit deliverable is the energyLAB energy audit report, containing our findings and recommendations in three energy management sections, namely:

  • Housekeeping
  • Operation & Maintenance
  • Capital works

Within these three sectors, we explain energy saving options and opportunities for your review and implementation.


Housekeeping measures are generally improvements involving virtually no cost, and involve relatively simple steps to start achieving energy savings. For example training courses to increase energy consumption awareness amongst your staff.

Operation & Maintenance

These improvements necessitate some change within your existing regime or maintenance strategy. For example lighting modifications, improved the switching arrangement or implementing a new lamp replacement strategy benefiting from the efficacy of the latest technology. In the majority of cases, the working environment for your customers is improved.

Capital works

Capital works would be major improvements to your premises or systems that will require significant expenditure. Examining your installation, analysing your operating and maintenance costs, and evaluating possible options for energy conservation. Viable proposals that will benefit you financially are offered for appraisal. For example switching to water cooled air conditioning (cooling towers) under the Hong Kong pilot programme or consideration of cost effective cogeneration solutions.

energylab energy conservation consultant, energy consultant, Hong Kong

Financial Analysis

The energy analysis would comprise a practical and economic evaluation of viable energy saving options. This evaluation would include an investigation of all the various elements that contribute to your owning and operating costs. Typically these would comprise:

  • Initial expenditure (CAPex)
  • Cost in use (OPex)

Investment analysis

Each of the elements would be analysed to gauge the overall economic viability of a particular energy-saving strategy or programme.

CapEx – is the initial expenditure, defines the money required to purchase plant or equipment.

OPEX – is the cost in use is the operating and running costs for the installation based on the data retrieved during the energy audit.

Investment Analysis – is the money side of capital works, comprising fiscal, payback and net present value calculations, these tools are primarily used to establish if a proposal would recoup your investment during a specific period. Payback hurdles would be established to meet the needs of the organisation.

hong kong energy consultant energyLAB

Energy Audit Standards

Is there any guideline for energy audits? Certainly, the process is structured, there are several published reference standards for energy auditing, including

  • EMSD’s BEC Energy Audit 2012
  • Energy Audit Guidelines – EMSD Hong Kong
  • ASHRAE Procedures for Commercial Building Energy Audits
  • Energy Audits Australian Standard AS 3598:2000

Note these guides/standards do not suite every project type.


The energy audit process can be sub-divided into three activities:

  • data collection
  • analysis
  • solutions reporting

Data Collection

The critical information for the audit is collected, for example the drawings, and energy bills, and also any identify any shortfall.


Based on the data collected, the energy consumption is reviewed, and opportunities to lower cost identified.

Solutions Report

The deliverable is the key, the report should clearly explain the opportunities to lower costs. However, those ‘energy standards’ mentioned earlier often require pages and pages of superfluous material which detract from the real energy auditing goal lower costs.

Success Story

Our long standing international expertise has helped design, auditing and implementation of energy audit recommendations, particularly our experience providing E&M capital works projects.

We have unique knowledge, gained across three continents, backed up with our experience from many years of Building design and operations. We help organisations lower operating cost to leverage a competitive advantage. Call the energyLAB energy audit experts today!

Project references include shopping centres, commercial buildings, leisure facilities, retail units and industrial facilities.

Commercial Building – We identified 30% annual energy savings

Shopping Centre – We identified 10% annual energy savings, with little no CAPEX

Hotel – We identified  15% annual energy savings, and uncovered design fixes to lower operating costs.

Every Watt Counts

Registered Energy Assessor (REA)

If you are choosing firm to ensure a Registered Energy Assessor (REA) who can perform energy audits in accordance the Hong Kong Building Energy Efficiency Ordinance (CAP 610).

John A Herbert

About John Herbert, REA

John has with more than 30 years of engineering experience gained across three continents and he is Registered Energy Assessor REA.
This entry was posted in energy audit and tagged , , . Bookmark the permalink.