Energy Savings Opportunity Scheme
ESOS is a UK mandatory energy assessment scheme for large undertakings. It requires qualifying organisations to conduct comprehensive energy audits covering at least 90% of their total energy consumption and identify cost-effective energy efficiency measures.
Who needs to comply
Large UK undertakings: 250+ employees, or £44m+ turnover and £38m+ balance sheet
250+ employees
Any UK undertaking employing 250 or more people
£44m+ turnover AND £38m+ balance sheet
Smaller headcount but meeting both financial thresholds
Corporate groups
If the highest UK parent qualifies, the whole group is in scope
Either the employee threshold OR both financial thresholds must be met.
What's required
The key disclosure and reporting requirements under ESOS.
Energy audit covering at least 90% of total energy consumption
Identification of cost-effective energy saving opportunities
Sign-off by an approved ESOS Lead Assessor
Notification to the Environment Agency of compliance
Consideration of all energy use: buildings, transport, and industrial processes
Action plan for recommended energy efficiency measures (Phase 3 onward)
How Climatise automates ESOS compliance
From raw data to audit-ready report — fully automated.
Complete Energy Mapping
Automatically categorise and map your total energy consumption across buildings, transport, and processes.
Savings Identification
AI-powered analysis identifies the most cost-effective energy efficiency opportunities in your portfolio.
ESOS-Ready Reports
Generate the documentation your Lead Assessor needs for Environment Agency notification.
Action Plan Tracking
Track implementation of recommended energy efficiency measures and quantify actual savings.
Frequently asked questions
The Energy Savings Opportunity Scheme is a UK government scheme that requires large enterprises to carry out audits of the energy used by their buildings, industrial processes, and transport, and to identify cost-effective energy saving measures.
Large undertakings in the UK: any organisation with 250+ employees, or those with annual turnover exceeding £44m AND a balance sheet exceeding £38m. If the highest UK parent company qualifies, all UK group companies are in scope.
ESOS operates in 4-year compliance phases. Phase 3 was due by 5 June 2024. Phase 4 will follow approximately 4 years later. You must re-audit and re-notify in each phase.
Related regulations
Explore other frameworks Climatise helps you comply with.
Automate your ESOS compliance
From raw data to audit-ready ESOS report in minutes. See how Climatise can save your team weeks of work.
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