What is ESOS?
ESOS is the UK Energy Savings Opportunity Scheme. It requires large undertakings to assess their energy use and identify cost-effective energy saving opportunities every four years, with assessments overseen by a lead assessor. Recent phases added action plans and progress reporting.
What it is
ESOS implements an energy audit obligation for large organizations. Each compliance phase runs for four years. Participants measure total energy consumption across buildings, industrial processes and transport, then audit the areas of significant energy consumption.
The assessment must be reviewed by a lead assessor, and a board level director signs it off. Phase 3 introduced action plans, in which participants set out the measures they intend to take, followed by progress updates. ISO 50001 certification covering all energy use can be a route to compliance.
Who it applies to / where it is used
ESOS applies to large undertakings in the UK, broadly defined by employee numbers or by turnover and balance sheet thresholds, and to group members of a qualifying group. The Environment Agency administers the scheme in England. Check the current guidance for qualification tests and deadlines.
How it is measured / what evidence it needs
The audit is a snapshot unless continuous data shows what happened after it.
- Total energy consumption for the reference period
- Audits covering areas of significant energy consumption
- Lead assessor review and director sign-off
- Action plans and progress updates
- Records kept for the required retention period
How Aqueduct helps
Continuous metered data replaces the four-yearly snapshot and evidences the action plan between audits.
- Metered energy by site, building and system across the estate
- Identification of significant energy uses from measured data
- Verified savings for each action through aQ EnergySmart
- Exportable progress evidence through aQ Assurance for the lead assessor