Energy Audits: Issues and Opportunities

Thursday, October 27, 2022

In current times with global concerns such as climate change (linked with greenhouse gas emissions), sustainability (particularly in regards to energy resources), and energy security; energy supply, consumption, and efficiency have become major issues.

Energy auditing of organisations and processes to determine energy supply, energy consumption, and energy efficiency is now frequently required in order to establish or improve:

• Organisation wide energy management programs (also known as an energy management system (EMS));
• Baselines for future comparison to track improvements in energy efficiency, reductions in consumption, and to compare the results of energy management initiatives;
• Benefits of specific actions implemented in order to reduce consumption and improve energy efficiency;
• Contributions to Greenhouse Gas Emissions.

The direct benefits of conducting energy audits include:

• Financial Benefits from reduced energy consumption and energy cost reductions (e.g. by changing suppliers, tariff or switching to renewables)
• Operational Benefits
  • Management Information
  • Working Conditions
• Environmental Benefits (e.g. switch to renewables, lower emissions fuel source or reduction of energy consumption).

Energy audits may be a requirement of Government Acts and Regulations, or voluntary programs with unlegislated requirements. Programs requiring energy audits, or where an energy audit provides much of the information required to meet program requirements include:

• NGER (National Greenhouse and Energy Reporting act);
• GRI (Global Reporting Initiative voluntary programme);
• NABERS (National Australian Built Environment Rating System regulatory for commercial building sector, voluntary for other sectors);
• GREEN STAR (Green Building Council of Australia voluntary programme).

The specifications for Energy Audits have been prescribed in international standards. Standards applicable to Energy Auditing include:

• AS NZS 3598.1:2014 Energy Audits
• AS/NZS ISO 50001:2021 Energy Management Systems Requirements with guidance for use.

The AS NZS 3598 defines three levels of audit (levels: 1 desktop, 2 walkthrough, and 3 detailed investigation of specific equipment or system/s) with each level having additional requirements over the level immediately below it. The energy user may decide on a single level of audit, or may start with a Level 1 audit and use the results to decide whether to progress to a level 2 or 3 audit. The content and time spent on an audit will vary depending on the size of the site and the cost of energy use for the site.

Alberfield’s experience in Energy Auditing has established that energy audits can have a very broad scope in complex and varied sites that will require investigation of weeks to months of data for key energy consumption related factors on site, such as hours of operation, staff levels, seasonal impacts, services provided at the site and plant and equipment. Recommendations addressing energy and associated emissions reductions and cost savings require a thorough understanding of the technologies and services utilised at the site. Key items considered during an Energy Audit include:

• Energy Policy & Management
• Environmental conditions (temperature, Heating Degree Days, Cooling Degree Days)
• GFA/NLA (Gross Floor Areas vs Net Lettable Areas)
• Units of production (e.g. Lettable Area, Number of Students, Patient Bed Days)
• Energy Billing, Metering & Tariffs
• Energy Sources, Consumption and Efficiency (e.g. gas, electricity, diesel, renewables)
• Building Fabric (e.g. Brick, steel, concrete, timber, insulation)
• Site Services (e.g. Electrical, HVAC, Lighting, Steam, DHW, Compressed Air)
• Site Assets (e.g. Power Generation, Electrical Infrastructure, HVAC equipment, Refrigeration, computers, printers)
• Site Asset Registers
• Site Maintenance Registers.

The scope of an Energy Audit is best defined at the beginning with a preliminary scoping study to help avoid cost overruns by establishing the quality and availability of relevant, detailed energy-related data required to complete the audit. This is generally achieved by conducting a level 1 energy audit. The audit is best delivered in separately quoted stages, progressing from level 1 to level 2 and then to level 3 where any areas are found that warrant further investigation requiring the level of effort and cost to complete a detailed investigation at level 3. In this way, the cost and likely benefit arising from each level of energy audit can be appropriately determined and aligned to ensure a favourable outcome for both the client and the auditor.

Information gathering and management is another important issue, with large amounts of data expected to be collected. This should be well planned and managed with the state of documentation having been determined either in a scoping study or initial level 1 energy audit to avoid spending expensive amounts of time in low level data collection. Access arrangements should be confirmed to facilitate collection of data, installation of measuring and logging equipment and to cover OH&S issues during on site work by the auditor/s. The demand for Energy Audits is expected to increase with the rising cost of energy for all — even those using renewable energy where it is distributed through a common grid supply or network.

For further information on this and other matters related to Energy Audits, contact Alan Carmody at Alberfield Energy on (08) 9418 7294 or info@alberfield.com.au.