Energy Savings Opportunity Scheme

Energy Savings Opportunity Scheme (ESOS)

ESOS is an energy assessment and energy savings scheme. It is mandatory for organisations that meet the qualification criteria. It derives from the EU Energy Efficiency Directive 2012/27/EU, art 8(4)-(6), which requires EU Member States to ensure that enterprises that are not small and medium-sized enterprises (SMEs) are subject to an energy audit carried out at least every four years.

For more information, see Practice Note: Energy Efficiency Directive 2012/27/EU—snapshot.

The requirements of the Energy Efficiency Directive, art 8(4)–(6) were implemented in the UK through the Energy Savings Opportunity Scheme Regulations 2014 (ESOS Regulations), SI 2014/1643. The Energy Act 2023 has granted powers to make necessary changes to ESOS post-Brexit, and the Energy Savings Opportunity Scheme (Amendment) Regulations 2023, SI 2023/1182 have made changes in advance of the Phase 3 compliance deadline.

Organisations that qualify must undertake an energy assessment and audit of their total energy consumption. In most cases the audit needs to be conducted or reviewed by a 'lead assessor', who must be a member of a professional body approved by the Environment