What is an Energy Audit in Manufacturing?

An energy audit is a thorough and effective method for finding powerful energy efficiencies in your manufacturing operation.  

Yes, there are things that you can do on your own, as a manufacturer, to find energy efficiencies.

There are even things you can do that require no capital investment (see our Complete Guide to Energy Efficiency in Manufacturing).

But if you want to quickly pinpoint the greatest opportunities for energy efficiencies, you’re going to need an energy audit. 

Also – In some countries, and in some industries, energy audits are mandatory. 

This article will help you understand what a manufacturing energy audit is, how they proceed, and what you can expect to get from them. 

We will also direct you to government resources to help you fund an energy audit for your manufacturing operation. 

This guide will help you understand: 

  1. What is an Energy Audit?  

  1. How to prepare for an Energy Audit 

  1. What does an energy audit report look like, and how do I use it? 

  1. Where to find government resources to help fund an Energy Audit 
Site visit - energy audit in manufacturing

What is an Energy Audit?  

An energy audit is a formal process that a manufacturer undergoes, with the help of a professional independent auditor. 

An energy audit helps a manufacturer understand: 

  1. The drivers of energy consumption, and how much energy they use 
  1. The greatest opportunities for saving energy in your manufacturing operation 
  1. How much money you can save, by taking the recommended energy-saving steps 

Benefits of a Energy Audit in Manufacturing

An energy audit of your manufacturing shop floor can help you understand your energy consumption, costs, and the impact those costs have on your profitability.  

An energy audit also helps you identify your priorities as you drive towards more energy efficient and sustainable operations. 

Beyond this, an energy audit helps you define the risks posed by volatility in energy costs, and provides guidance as to how you can manage those risks going forward. 

It is recommended that manufacturers complete an energy audit approximately every four years

What Happens during an Energy Audit? 

In an energy audit, a professional auditor visits the manufacturing facility and assesses the site, cells and machines that are within the scope of the audit. The manufacturer will work closely with the auditor to provide operational context. 

The end product of an audit is a detailed report that provides an analysis of the energy usage of the audited site, cells, machines and processes.  

Additionally, the report presents a prioritised list of recommended energy-saving opportunities, supported by the underlying financial-impact calculations. 

The report will be a useful reference in the years to come to make capital investment decisions for the manufacturing operation. 

There are three main phases of an energy audit: 

  1. Pre-Audit: Steps the manufacturer & the auditor take prior to conducting the site visit 

  1. Conducting the site visit 

  1. Analysing the audit’s findings and providing recommendations 
Factory Floor - How can an energy audit in manufacturing help?

The depth of the energy audit is up to the manufacturer. You can choose a light audit, which only looks at a handful of manufacturing systems at a high level. Or you can choose an in-depth analysis. It all depends on your energy-saving goals. 

Governmental entities often provide funding to help manufacturing organisations carry out an energy audit, as energy efficiency is a goal that benefits society in general.  

What is Assessed in a Energy Audit for Manufacturing? 

The on-site visit can take as little as a few hours, or a full day, depending on the agreed scope of audit.   

Here are some of the areas, machines and processes that are typically assessed in an energy audit: 

  • Building 
  • Lighting 
  • Heating and boilers 
  • Production machinery 
  • Pumps 
  • Transport fleet, telematics 
  • Refrigeration 
  • Industrial processes 
  • Wastewater treatment 
  • Compressed air 

For each area, machine and  process assessed, an auditor is typically looking at these: 

  1. Physical state, function and energy usage 

  1. Opportunities to save energy  

  1. Major risks  

See below for some examples of the above. 

Physical State, Function and Energy Usage 

Examples of physical state, function & energy usage assessed in an energy audit: 

  • Heat pumps are properly recovering energy from cooling loads 
  • Excessive air leakage in ovens, furnaces or extraction systems 
  • Production machine rated at 16KW and is in fact consuming at that rate during production runs 
Shop floor

Opportunities to Save Energy 

Examples of opportunities to save energy uncovered in an Energy Audit: 

  • Identifying and correcting set points for refrigeration systems can reduce the energy required 
  • Using a different form of energy in a particular process, e.g. gas instead of oil or electricity instead of gas
  • Addressing issues in broken or poorly maintained windows and doors could lead to lower heating or cooling needs 

Major Risks 

Examples of Major Risks that could be uncovered in an Energy Audit for Manufacturing: 

  • Excessive energy usage by process critical production machinery resulting in maintenance issues and costly downtime 
  • Issues with heating or boilers may lead to a need to shut off water systems completely for a period of time, which could result in corrosion and leakage in distribution systems 
  • Neglect of building air-tightness may lead to a need to perform deep retrofits, which could disrupt production altogether. 

Post Audit – Financial Analysis and Prioritisation of Energy Efficiency Opportunities 

After the site visit, the auditor uses the measurements obtained during the audit to find opportunities for energy-saving measures. The auditor then generates financial analyses of different measures – to estimate their potential cost-savings impact. 

The auditor can make use of different financial analysis methods when generating financial impact estimates.  Some financial analysis methods are more rigorous, such as net present value (NPV) calculations or lifecycle costing (LCC). Other financial analysis are more quick-and-dirty, such as payback period.  

The financial analysis method chosen is determined by the importance of the machine or process being assessed. Generally, such assessment methods are determined prior to the site visit, as a part of the scoping stage. 


How to Prepare for a Energy Audit in Manufacturing

The first step in an energy audit process is finding a qualified auditor.  

In Ireland, a current list of the names & locations of registered energy auditors can be found on the SEAI website

Prior to conducting an energy audit, the manufacturer & auditor conduct these steps: 

  1. Agree to the scope of the audit 

  1. Gather key information, such as electricity bills, meter registration numbers, etc. 

  1. Identify key manufacturing personnel for helping with the audit 

  1. Identify baselines for energy usage of machines & shop floor 

  1. Develop an audit checklist, outlining machines, processes etc. to be assessed 

A full list of pre-audit steps can be found in the SEAI Energy Audit Handbook

Energy audit in manufacturing - audit report

What does an Energy Audit Report Look Like, and How do I Use it?   

The audit report is the end product of the audit process.

The report provides details of the findings of the audit, with a depth of detail that corresponds to the previously agreed audit scope. However all audit reports should provide sufficient detail to allow the manufacturer to verify the recommendations and supporting calculations.  

Details of an energy efficiency audit report include: 

  • Energy consumption and costs, for the overall operation and for individual machines & processes 
  • Comparison of energy usage versus known benchmarks 
  • Details on significant energy using machines or processes 
  • Details on the operations’ energy metering and measuring systems 
  • A prioritised list of opportunities for increasing energy efficiency
  • Calculations used to derive financial impact figures  
  • Recommended next steps 

The report is a deliverable from the auditor that is owned by the manufacturer who can then use it as a reference for making investment decisions.  

Where can I Find Government Resources to help Fund an Energy Audit   

Governments often provide financial aid to help manufacturing operations undertake energy audits. This is because it is in the best interest of society to preserve energy resources. 

Government financial aid typically comes in the form of: 

  1. Grants 

  1. Tax incentives 

In Ireland, the government provides grants of up to €2,000 towards the cost of an energy audit. In most cases, the Irish government grant covers the entire cost of an energy audit. 

For more on the Irish scheme for energy audits, or to submit an application, consult the SEAI website

For an example of tax incentives, we can look to the US. In the US, a commercial entity can reduce their tax burden by retrofitting factory floors in ways that increase energy efficiency.

The Commercial Energy Efficiency Tax Deduction allows US manufacturers to subtract $5 from their business taxes owed for every retrofitted square foot of shop space. 

Contact Mavarick to Learn about Energy Management Systems

To find energy efficiencies on your own, or to make the most of an energy audit’s recommendations, you’ll need an Energy Management System.

An Energy Management System is a solution for measuring and monitoring your operation’s energy usage.

Contact Mavarick today to learn about our solutions for manufacturing production and energy management.