ESOS Phase 3 Changes Summary

Esos Phase 3 Changes Summary 529x298
Esos Phase 3 Changes Summary 529x298

ESOS Phase 3 Changes Summary 

Changes brought in by the Statutory Instrument (Energy Act)

Strengthening requirements for audits/standardisation:

  • Requires participants to audit at least 95% of total energy consumption – this was previously at least 90%.
  • Requires responsible undertakings to lay out more detail in respect of the calculation of participants’ energy consumption, including energy intensity ratios.
  • Requires participants to explain how the site visits that are carried out for energy audits are considered to be representative of energy use covered by the audit.
  • Requires all participants to produce an ESOS report, including those using alternative compliance routes such as the ISO 50001 energy management system, and requires specific data to be included. This includes information on energy savings made since the previous compliance date.
  • Requires the responsible undertaking to disclose to all members of the corporate group certain relevant information from the ESOS report and relevant supporting information relating to alternative compliance routes.  Improve the quality of ESOS audits
  • Specifies information that must be identified in relation to energy saving opportunities, including their costs, benefits and a programme for implementing them. Require public disclosure of high-level recommendations by participants
  • Requires additional information to be notified to the scheme administrator in relation to the participant’s energy consumption and other information to support compliance monitoring and enforcement.
  • Following the submission of the compliance notification (by 5 June 2024), requires participants, including those relying wholly or partly on alternative compliance routes, to produce and notify an ESOS action plan to the scheme administrator (by 5 December 2024) setting out any commitments to implement energy efficiency measures, and requires them to provide annual progress updates against actions they have committed to.
  • Requires some of the additional information that is required to be notified to the scheme administrator, as well as action plans and progress updates, to be publicly disclosed.

Other provisions

  • Extends the deadline for compliance with phase 3 of ESOS, including extending the dates in relation to most of the supporting data used, to allow participants more time to comply with phase 3 of ESOS, given the change made by these regulations.
  • Puts into legislation an exemption from appointing a lead assessor for participants whose energy consumption is less than 40,000 kWh, but adds a requirement for two directors to sign off the compliance notification in this case.
  • Sets out responsibilities for the action plan and subsequent progress updates where there are changes to a corporate group.
  • Introduces specific requirements where estimates are made under the regulations.
  • Applies the legislative changes to relevant trust assets.

Formal and detailed guidance relating to Phase 3 reporting requirements is provided in the Comply with the Energy Savings Opportunity Scheme guidance document.

Compliance Notification Changes

New ESOS Digital Service for Phase 3 compliance notification

A new online notification system will replace the 'SmartSurvey' system used in ESOS Phase 2.  At the time of the publication of this post, the new system is undergoing testing, including sessions with volunteers to provide user feedback.

Important change: Responsible Undertakings reporting ESOS compliance will create a user account. Responsible Undertaking can add an external Lead Assessor to complete Notification of Compliance. The Responsible Undertaking, and not the Lead Assessor, will be responsible for submitting this information.

Details on the information that is required to be submitted are set out in Appendix B of the online guidance on complying with ESOS, on

Useful Contacts

  • Contact the Environment Agency helpdesk at [email protected] to:
    • Ask any further questions on ESOS guidance or how the legislation is applied
    • Join the ESOS mailing list
  • Contact the Department for Energy Security and Net Zero (DESNZ) at [email protected] to:
    • Ask any further questions on the ESOS notification system