As you probably know, an energy audit is mandatory for all large companies, including industry. However, it is only one step in improving your energy management, and can be complemented by an advanced audit to establish an operational roadmap. Find out everything you need to know about the energy audit in this article.
Changes in the regulatory energy audit in 2024
Industrial energy audits in brief
The regulatory energy audit is an essential tool for assessing and optimizing your company's energy needs. In accordance with European Directive 2012/27/EU, companies with more than 250 employees or sales in excess of €50 million must carry out this audit every four years. The aim? To carry out a complete assessment of energy-intensive utilities and processes, in order to draw up a precise action plan to save energy and reduce your CO2 emissions.
Good to know: Changes are planned in the European Union's new Energy Efficiency Directive (EED): from October 11, 2026, all companies whose average annual energy consumption has exceeded 10 TJ (total annual energy consumption between 2.7 and 23.6 MWh) over the last three consecutive years, will have to undergo an energy audit every 4 years. They can also choose to have their Energy Management System (ISO 50001) certified, thus substituting it for the audit if it covers at least 80% of consumption.
Contents of a regulatory energy audit
Since January 1, 2024, regulatory industrial audits must comply with level 2 as defined by standard NF 16 247-3. More specific, this level of audit focuses on targeted and detailed improvement measures, to optimize energy efficiency in an industrial context.
Thus, the industrial energy audit must imperatively include:
- A site visit (NB: also required for a level 1 audit);
- Measurement of a minimum of 3 Significant Energy Uses (SEUs), each representing a minimum of 10% of the site's total consumption;
- A verification or redefinition of the correct thermal match between needs and production;
- An identification of waste heat rejection temperatures and recoverable energies;
- The establishment of an energy-saving action plan
- The definition of an action plan for the use of RE.
The action plan of the mandatory industrial energy audit characterizes and prioritizes each action according to various criteria:
- Emission reduction (tCO2eq/year)
- Energy savings (MWh/year)
- Energy savings (€/year)
- Investment costs (k€)
- Subsidies identified (k€)
- Payback time based on Net Present Value (NPV)
EU-ETS sites are required to implement actions with a payback time of less than three years.
While it enables you to comply with the law, this type of audit rarely commits you to the implementation of a concrete action plan. Indeed, such implementation can only be based on a comprehensive action plan that includes both utilities and processes, and prioritizes measures to improve energy efficiency, taking into account both economic and environmental criteria.
Taking action with an advanced audit
An advanced energy audit results in a tailored action plan that incorporates specific process-related measures. This type of action plan also optimizes the identification of available subsidies.
Please note: If your objective is solely to meet regulatory constraints, without necessarily following up your audit with a process to reduce your energy consumption, the advanced audit is not necessary.
Energy mapping: a precise analysis for an operational action plan
Energy mapping is a key stage in the advanced audit. It consists in carrying out more numerous and detailed measurements, in order to provide an exhaustive analysis of energy flows. In concrete terms, it involves examining the energy requirements for each stage in the transformation of your products, in order to optimize the resulting energy uses. The longer the measurement period, the more accurate the mapping.
A mapping must answer these three questions about your energy consumption: at what stage, where and when?
At what stage of transformation?
From the data collected, a synoptic representing the activity of the production lines highlights the most energy-intensive process stages and the possibilities for energy counter-exchanges, providing an overall energy view. Power measurements for each station help to identify possible optimizations at station level, but also on the overall process.
Where on the site?
A topography of the various energy stations provides the location information needed to assess the feasibility and network costs of the solutions envisaged.
At what point?
The aim here is to model the thermal requirements of your processes over time. To do this, we need to take into account variables that influence them:
- Variations in production activity (rates, quantities produced) ;
- Weather conditions (temperature, humidity);
- Equipment operating conditions (thermal levels, pressure).
Over a representative period, this modeling breaks down energy requirements by thermal level and compares them with utility energy production.
Client case - LEMON ENERGY carried out an advanced audit for a major dairy products plant, culminating in a roadmap forecasting 20 GWh / year of energy savings. Thanks to this audit report, the site has drawn up a precise plan for achieving the ambitious targets set by head office. We carried out a complete assessment of the site, mapping energy performance item by item and providing a schematic diagram for each recommendation. The audit was carried out in coordination with all stakeholders (in-house managers and external service providers) and in collaboration with the site's R&D team, in order to verify the impact of the proposed solutions on product quality. In addition to the audit, we carried out a feasibility study for the recovery of heat from wastewater. Our entire service was 50% financed by ADEME.
Determining an operational roadmap
An audit report generally identifies several avenues for improvement in energy management. Improving your company's energy efficiency may mean prioritizing them. The advanced audit will script the implementation of recommended actions, according to your criteria.
To articulate the actions in a roadmap, several steps are necessary:
Categorization
Actions can be of different kinds, ranging from simple maintenance and process adjustments to more complex reorganizations or targeted investments.
Hierarchization
The priority of actions varies according to their impact on reducing energy consumption and their economic and technical feasibility.
Grouping
The roadmap must integrate the compatibility of actions with each other to achieve your objectives, considering the savings achievable according to a defined CAPEX or payback time, as well as the planned evolutions of your facilities and business.
Client case - LEMON ENERGY carried out an advanced audit for a major chemical site, culminating in a full-cost roadmap to support their investment strategy. This roadmap provides for 5 GWh /year of energy savings and a reduced payback time of five years thanks to the eligible grants we identified.
Prepare a measurement plan to monitor your action plan
In order for your action plan to be fully operational, it's important to plan, right from the audit phase, how you're going to measure the impact of the planned actions. To do this, you need to take stock of existing data, which will lead to the establishment of Energy Performance Indicators (EPI). An EPI is a ratio that makes it possible to compare and track over time the performance of the energy uses to which it is associated.
These indicators are built up from data:
- From sensors (electricity, gas, water, compressed air...)
- From production (machine hour, air flow, water flow...)
- Weather conditions (outside temperature, humidity...)
Have a complete Energy Metering Plan drawn up, detailing data collection and processing methodology, as well as a list of sensors and energy performance indicators.
To wit: This document is an essential tool for implementing effective energy monitoring, and can be used to draw up technical dossiers for Energy Savings Certificates (CEE IND-UT-134).
If you want to comply with the law, a regulatory audit is a must. But if you want an operational action plan that will enable you to achieve the ambitious decarbonization targets you've set yourself, bet on the advanced audit, whose cost can be recouped by the energy savings actually achieved. Good news: the advanced audit can be financed up to 50% by ADEME, under certain conditions. Contact us to find out more about energy audits, and to help you find the right funding.
