Obligations and advantages of energy diagnosis

By 5 December 2019, an energy diagnosis is mandatory for large companies and energy-intensive companies


Legislative Decree no. 102 of 4 July 2014 introduced the obligation of energy diagnosis for large companies and energy-intensive companies. The diagnosis must be carried out every four years and the next deadline is 5 December 2019 and concerns the 2018 energy consumption data.

The same decree was modified by Legislative Decree. n. 141/2016, which provided the definition of energy diagnosis (or energy audit): “a systematic procedure aimed at obtaining adequate knowledge of the energy consumption profile of a building or group of buildings, of an industrial activity or plant or commercial or public or private services, to identify and quantify energy saving opportunities from a cost-benefit perspective and to report on the results.”

The obliged subjects

The subjects obliged to carry out the energy diagnosis are companies that belong to one of the following two categories:


• large business: companies with more than 250 employees and an annual turnover of more than 50 million euros or companies with more than 250 employees and an annual budget of over 43 million euros (also taking into account the associated or connected companies).

• energy-intensive companies: highly energy-intensive companies included in the CSEA (Environmental Energy Services Fund) list of energy-intensive companies in the year preceding the obligation.


Pursuant to the MiSE Decree of 12/21/2017 and the ARERA Resolution 921/2017/R/EEL, from 2018 an energy-intensive company is such if it has an electricity consumption > 1.0 GWh/year and one of the following requirements:


• operate in the sectors of Annex 3 of the EC Guidelines

• operate in the sectors of Annex 5 of the EC Guidelines and have an energy intensity index on VAL ≥ 20%

• included in the lists of energy-intensive companies for the years 2013 or 2014


Companies that have implemented a Management System compliant with Emas, ISO 50001 or EN ISO 14001 which includes an energy audit compliant with Legislative Decree no. are exempt from the obligation. 102/2014.

In the case of multiple production sites belonging to the same company, it is necessary to choose those that are representative of the company’s overall consumption.


There are sanctions ranging from €4,000 to €40,000 for failure to carry out the diagnosis and from €2,000 to €20,000 for the carrying out of a diagnosis that does not comply with Annex 2 of Legislative Decree no. 102/2014. In addition to paying the fine, the company must still carry out the energy diagnosis (within 6 months of the fine).

The working phases of the energy diagnosis

The process includes an initial phase of analysis of the company’s current state of affairs followed by the definition of the intervention plan.

In particular, the work phases include:


• Data collection for the analysis of energy consumption and related costs in the bill;

• Inspection to complete data collection;

• Identification of consumption “centres” (with the aid of any consumption monitoring data) and of the conditions of inefficiency and dispersion, with a critical analysis and comparison with average consumption and cost parameters;

• Definition of energy efficiency interventions and priority level based on investment costs, energy and economic savings, return times of the interventions;

• Evaluation of possible economic contributions deriving from Energy Efficiency Certificates, the Thermal Account, tax deductions or other possible incentives.


Focus on consumption monitoring

The first aim of an energy diagnosis according to Directive 2012/27/EU is to measure consumption, allowing us to know the methods of energy use and the energy consumption profiles, in order to identify effective efficiency solutions.

A company that sees bill costs rising should begin a process of optimizing the internal energy distribution and use system, first of all identifying which cost centers have the greatest impact on consumption. This is possible starting from a reconstruction of the internal energy flows through fixed or portable measurement instruments and analyzing the powers installed in the various departments and the operating hours of the various machinery. Monitoring consumption therefore becomes an opportunity to reduce consumption (therefore costs) and becomes the indispensable tool for identifying preferential areas in which to implement energy saving measures.

The ministerial clarifications of November 2016 report: “If measurements using dedicated meters are not available, for the first diagnosis, the calculation of the energy data of each functional unit is obtained from the available data” and adds: “Once the set has been defined of the functional areas and having determined the energy weight of each of them by means of design and instrumental evaluations, the implementation of the permanent monitoring plan must be defined in order both to keep significant data of the company context under continuous control and to acquire information useful to the management process and give the right energy weight to the specific product created or the service provided.”

In this way it is understood that in the diagnoses subsequent to the first for the functional areas there must be dedicated counters, that is, not so much a complete monitoring system dedicated to them, but a “monitoring strategy” which, through appropriate coverage of instrumentation, control and management, ensures that the energy parameters relating to them can have increasing reliability with the progressive implementation of said systems (ENEA – Guidelines for Monitoring in the industrial sector for energy diagnoses pursuant to art.8 of Legislative Decree 102/2014).

For the next diagnosis cycle (obligation by 5 December 2019 for those who fulfilled the obligation in 2015) it will be necessary to measure within certain limits the energy vectors being analyzed through measurements compliant with the national and international reference standards (ISO, UNI, IPMVP protocol, etc.).