A major change to EU energy-efficiency rules is moving mandatory business energy audits away from company size and towards actual energy consumption. Enterprises averaging more than 10 TJ, approximately 2.78 GWh, a year over the previous three years can fall within the new audit requirement, with the first audit deadline set for 11 October 2026.

For some Irish businesses, that creates an obligation that may not have applied under the existing Irish audit regime.

The important number is no longer simply employee count or turnover. It is energy use.

The 2.8 GWh threshold changes who falls into scope

Article 11 of Directive (EU) 2023/1791 requires enterprises with average annual energy consumption above 10 TJ over the previous three years, taking all energy carriers together, to undergo an energy audit where they do not implement an energy management system.

Ten terajoules is approximately 2.78 GWh, or 2.78 million kWh.

The European Commission’s implementation guidance says the assessment is based on average annual final energy consumption over the previous three years. For a 2026 assessment, that means the relevant consumption history is effectively the preceding three years rather than a single unusually high or low year.

That is a significant change in approach.

A relatively lean business by employee numbers can still consume substantial energy through refrigeration, manufacturing, process heat, HVAC, data processing or extended operating hours. Under the recast Directive, consumption becomes the determining factor.

The threshold covers more than the electricity bill

The 2.8 GWh figure is an energy threshold, not a euro-spend threshold.

The Commission’s guidance states that all energy carriers and energy uses should be considered. That can include electricity, heating and cooling, transport energy and energy used by production processes, data storage, lighting and ventilation.

A business using 1.8 GWh of electricity and another 1.1 GWh equivalent through gas or other fuels could therefore be in a very different position from one looking only at its electricity account.

Energy costs are also a poor proxy for the threshold. The same amount of energy can carry very different costs from year to year as wholesale prices, tariffs and contract structures change.

The compliance test is consumption.

The first audit deadline is 11 October 2026

The Directive requires the enterprises caught by Article 11(2) to complete a first energy audit by 11 October 2026. Subsequent audits must take place at least every four years.

That does not necessarily mean every enterprise above the threshold starts again from zero.

The Commission’s implementation recommendation allows for circumstances where a sufficiently recent energy audit is already available. Its guidance indicates that an audit less than four years old can be relevant when determining the next audit requirement.

The immediate task is therefore to establish consumption first, then establish what qualifying audit or energy-management work is already in place.

The deadline matters only after the scope has been established correctly.

Ireland’s existing audit scheme still uses the older criteria

Ireland already operates an Energy Auditing Compliance Scheme through SEAI under S.I. No. 426 of 2014, as subsequently amended.

That legislation currently requires companies that are not SMEs to carry out energy audits. SEAI’s published compliance guidance continues to identify businesses principally through the existing tests of 250 or more employees, or annual turnover above €50 million together with a balance-sheet total above €43 million.

SEAI states that qualifying audits under the existing Irish scheme must generally be repeated every four years and that obligated organisations must notify SEAI of compliance. Its current guidance also requires the audit scope or qualifying management-system route to cover at least 85% of delivered energy use in the Republic of Ireland.

The recast EU Directive changes the underlying logic from enterprise size to energy consumption.

As of 18 August 2026, SEAI’s public Energy Auditing Compliance Scheme page still displays the existing Irish size-based criteria. SEAI separately states that it is participating in the EU-funded “Leap to 11” programme to support Member States with the transposition and implementation of Article 11 of the recast Directive.

Businesses close to the threshold should therefore follow updated SEAI and national guidance as the October deadline approaches rather than assuming that being classified as an SME automatically places them outside the new regime.

The old SME test is no longer a reliable measure of future audit exposure.

The audit is intended to produce an action plan, not simply a compliance report

The Directive defines an energy audit as a systematic assessment of an organisation’s energy profile designed to identify and quantify opportunities for cost-effective energy savings. The scope can include buildings, industrial or commercial operations, installations and services.

Article 11 goes further than simply requiring an audit document.

Enterprises covered by the provisions must draw up a concrete and feasible action plan based on the recommendations arising from the audit or energy management system. The Directive requires the action plan to identify measures for implementing recommendations where technically or economically feasible, and provides for publication of the action plan and recommendation implementation rate.

That changes the commercial value of the exercise.

An audit can identify excessive baseload, poorly controlled HVAC, refrigeration losses, inefficient lighting, weak building controls, process inefficiencies, metering gaps, renewable-energy opportunities and projects requiring further capital assessment.

The regulatory requirement is increasingly tied to what happens after the audit.

Businesses above 23.6 GWh face a different requirement

Article 11 contains a second, substantially higher threshold.

Enterprises averaging more than 85 TJ, approximately 23.61 GWh, a year over the previous three years must implement an energy management system. The Directive requires that system to be certified by an independent body in accordance with relevant European or international standards, with a deadline of 11 October 2027.

This is different from commissioning an energy audit every four years.

An energy management system creates an ongoing framework for setting energy objectives, monitoring consumption, measuring performance and managing improvement over time.

For Ireland’s larger energy users, the 2026 audit deadline and the 2027 energy-management deadline should therefore be considered together rather than as separate compliance exercises.

Above 23.6 GWh, energy management becomes a continuing system rather than a periodic review.

The first calculation can be done from existing energy data

Most businesses do not need to begin with a site survey to establish whether the 2.8 GWh threshold is relevant.

Electricity and gas invoices, interval data, supplier consumption statements and records for oil or other fuels can be used to build the initial consumption picture. The important step is to convert the different energy carriers to a common energy unit and calculate the three-year annual average.

For a business operating several sites or using energy outside its main electricity account, the calculation needs more care. The Commission’s guidance treats an enterprise broadly as an entity engaged in economic activity irrespective of its legal form, while the Article 11 calculation is based on the energy consumption of the enterprise.

This is where relying on a single bill or a single premises can give the wrong answer.

The threshold calculation should come before the compliance conclusion.

October is close enough for businesses to establish their position now

The 11 October deadline is less than two months away.

For businesses near or above 2.8 GWh, the immediate issue is not whether an energy-saving project should be installed. It is whether the enterprise is within scope, whether an existing audit or management system is relevant, and what route will satisfy the final Irish compliance requirements.

Energy Matters Ireland can review recent electricity, gas and other energy data to estimate the three-year consumption position and identify whether the 2.8 GWh or 23.6 GWh thresholds appear relevant.

Where an audit is required, the resulting work can also provide the basis for assessing energy-efficiency projects, procurement exposure and relevant grant supports.

Businesses that want an initial scope check can send Energy Matters Ireland their 2023, 2024 and 2025 energy bills or annual consumption data.

The October deadline is fixed in the EU rules. The first decision is establishing whether the business crosses the line.

Businesses Above 2.8 GWh Face an Energy-Audit Deadline on 11 October 2026