Energy Savings Opportunities Scheme


The Energy Savings Opportunity Scheme (ESOS) has been established to implement Article 8 (4-6) of the EU Energy Efficiency Directive. The scheme is administered by the Environment Agency and is mandatory for all organisations (private, public and voluntary sector) that meet the following qualification criteria:

Any UK company that either:

  • employs 250 or more people, or

  • has an annual turnover in excess of £38,937,777, and an annual balance sheet total in excess of £33,486,489

  • is part of a corporate group which includes a UK registered establishment which exceeds the above thresholds.


Organisations that meet the stated criteria must carry out assessments every 4 years to audit the energy used by their buildings, industrial processes and transport and identify cost-effective energy saving measures and then notify the Environment Agency by a set deadline that they have done so. The first notification of compliance should have been submitted by 5 December 2015. The process will then have to be repeated at the end of every 4-year compliance period, ending on 5 December 2019, 2023 and so on.

Whether or not organisations participated in the first phase of ESOS, they are obliged to participate in phase 2 if they qualify on December 31st 2018. They can choose any 12 month audit period that includes the qualification date. 

There is an extensive section on ESOS, including a downloadable compliance guide and details of penalties for non-compliance, on the government's website.