Mandatory energy audits

European Directive 2012/27/EU on energy efficiency introduces compulsory energy audits for companies that are not SMEs.


This obligation is enacted in Luxembourg by the Law of 5 August 1993 on the rational use of energy as amended by the Law of 5 July 2016 amending the amended Law of 5 August 1993 on the rational use of energy (referred to as the “Law of 1993”).


1. Which companies are affected by this obligation?

All companies that are not SMEs, regardless of their legal form, are required to carry out periodic energy audits every four years.


To determine whether a company is effectively bound by this obligation, the company in question must check its status by referring to the workforce and financial criteria set out in Annex I of Regulation (EU) No 651/2014. The regulation also provides details on how to take into account any data from partner and related companies.


Exceeding one of the following thresholds (not exhaustive) makes the company eligible for an energy audit:

  • its workforce is larger than or equal to 250 persons;
  • its annual turnover exceeds 50 million euros and its annual balance sheet total exceeds 43 million euros.


2. What should be the content of the energy audit?

The audit must meet the minimum criteria provided for in Article 11, paragraph 6, of the Law of 1993, namely:


  • be based on up-to-date, measured and traceable operational data on energy consumption and, in the case of electricity, load profiles;
  • include a detailed review of the energy consumption profile of buildings or groups of buildings, as well as industrial operations or facilities, particularly transportation;
  • where possible, use a life cycle costing analysis rather than simple depreciation periods to take into account long-term savings, long-term investment residual values and discount rates;
  • be proportionate and sufficiently representative to provide a reliable picture of overall energy performance and accurately identify the most significant opportunities for improvement.


It is recommended that the energy audit comply with international standards for energy audits, particularly EN 16247.


With regard to the scope of the energy audit, the recommendation is that the scope of analysis should cover at least 80% of the energy consumption used to achieve the company's purpose. This scope includes rented buildings and leased cars. However, temporary construction sites are excluded.


Companies whose energy consumption does not exceed 100 MWh can perform a simplified energy audit that takes into account the cost-effectiveness of the audit. In other words, the audit must be proportionate, in its degree of detail and in its scope, to the energy consumption of the company. The audit must nevertheless include the four criteria listed above.


3. Who can carry out an energy audit?

The Ministry of the Economy maintains a list of "qualified or accredited experts" who meet the criteria of the Law of 1993. This list is available on the website


Alternatively, experts within the companies can also carry out energy audits. Internal auditors do not need accreditation but must be qualified in the sense that they fulfil the criteria referred to in points a) to e) of the same Article 11bis, paragraph 2.


4. Is state aid available to carry out mandatory energy audits?

Insofar as energy audits meet a legal obligation, no subsidy can be allocated for this purpose.


5. How is this monitored?

The Law of 1993 states that energy audits are to be carried out by large companies within five months of entry into force of the Law of 5 July 2016, i.e. by 10 December 2016. After this period, the Minister for Energy may carry out a check to ensure that the audits have been performed. Failure to comply with the legal obligations may result in sanctions.


In addition, audited companies must ensure that data and reports on the energy audits performed are archived for at least ten years.


6. Are waivers permitted?

Energy audits carried out as part of an energy (e.g. ISO 50001) or environmental (e.g. ISO 14001) management system do not have to be carried out by an approved auditor but must meet the minimum criteria set out in Article 11 of the Law of 1993.


In the event of an inspection, the companies concerned will have to provide their ISO certificate as well as a copy of the energy audit carried out as part of the energy or environmental management system in place. This energy audit will nevertheless have to comply with criteria equivalent to those laid down in Article 11, paragraph 6, of the Law of 1993.


However, it should be noted that the implementation of such an energy or environmental management system involves indirect costs (system administration, staff training, energy reviews, certification, etc.), which the company must take into account before deciding whether to implement such a system.


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