You can also call us on +44 (0)20 7170 7000, or select 'Live Chat' to chat with one of our advisors

Comply with ESOS: UK Energy Savings Opportunity Scheme

All large UK organisations outside the public sector are affected by the Energy Savings Opportunity Scheme (ESOS) regulations. Find out how your organisation can go beyond compliance, implement energy efficiency and cut costs now to take advantage of the real opportunities in ESOS.

As a mandatory scheme, all large UK organisations outside the public sector are affected by ESOS. The Carbon Trust provides a complete suite of services to help organisations achieve compliance with the ESOS regulations in a cost-effective and efficient manner and turn energy-saving opportunities into real business advantage.

As the UK’s leading mission-driven, 'not-for-profit' organisation helping businesses to accelerate the move to a sustainable low carbon economy, the Carbon Trust is uniquely placed to help organisations comply with the ESOS regulations and go beyond compliance to take advantage of the business opportunities in energy efficiency. We bring a wealth of experience to bear and have worked with over 200 companies to help them comply with ESOS, while reaping the business benefits of energy efficiency.

On this page:

Get in touch

Email us

Call us on +44 (0)20 7170 7000

Or fill in our contact form

What is ESOS?

The ESOS Regulations 2014 bring into force Article 8 of the EU Energy Efficiency Directive and mandate that large organisations in the UK undertake comprehensive assessments of energy use and energy efficiency opportunities at least once every four years.

Who is affected?

The criteria for inclusion to ESOS is not entirely straightforward, but essentially it applies to any large undertaking that carries out a trade or a business (most commonly a Company), and any corporate group where at least one member of the UK group meets the ESOS criteria.

  • A large undertaking is one that employs at least 250 people,
  • Or has an annual turnover in excess of €50 million and a balance sheet in excess of €43 million.
  • Most public sector bodies are excluded, but other organisations that receive some public funding, such as universities, may qualify.

ESOS Phase 2

We’re now in Phase 2 of the ESOS compliance scheme. Organisations were required to submit information for Phase 1 of ESOS by 29 January 2016. The regulations require large UK organisations to take three important steps before the compliance date of 5 December 2019:

  1. Measure total energy consumption for buildings, industrial processes and transport
  2. Conduct audits to identify cost-effective energy efficiency recommendations for areas of significant energy consumption; and
  3. Report compliance to their national scheme administrator – the Environment Agency in England, SEPA in Scotland, NIEA in Northern Ireland and NRW in Wales.

To comply with the regulations, a Lead Energy Assessor will need to conduct the ESOS Assessment.   In certain cases organisations can comply automatically. The main way to do this is by providing evidence that they have achieved certification to ISO 50001, the international standard for best practice energy management, across their organisation.   

Act now to identify Phase 2 opportunities

Organisations caught under the ESOS regulations can now start conducting audits to identify their cost-effective energy efficiency opportunities in order to meet the requirements of the Phase 2 compliance period, or move forward with implementing ISO 50001. In particular ISO 50001 requires early action, as it often takes well over a year for companies to implement a best practice energy management system and achieve certification.

Organisations can also now begin collecting the data for reporting their total energy consumption, as ESOS compliance requires a 12 month period of total energy consumption data which includes the qualification date of 31 December 2018.

Read more in our viewpoint: ESOS Phase 2 has arrived – start planning for how to get maximum value from going through the compliance process.


Contact us to find out how we can help you prepare for Phase 2

Keepmoat has found the ESOS process to be of significant benefit to the business, highlighting opportunities for increased awareness and cost savings across our offices, fleet and construction activities. In partnering with the Carbon Trust, we have benefitted from unrivalled expertise in energy management combined with an effective and supportive team.
David March, Group Environmental Manager, Keepmoat

How we can help you with ESOS Compliance

The qualification criteria and requirements of ESOS are complex and many organisations will need to take substantive steps in order to comply.  We offer a modular set of ESOS services to help companies achieve compliance in a cost effective manner, whilst at the same time highlighting the options for reducing energy consumption and maximising the associated business benefits.   With qualified Lead Energy Assessors available to review and guide the approach, our ESOS services can provide support right the way through to full ESOS Compliance. 

Number of organisations we supported during the first phase of ESOS
Number of organisations we supported during the first phase of ESOS

Carbon Trust's ESOS services

Our ESOS services are based on a modular approach that allows services to be selected depending on your individual circumstances:

  • Delivery of organisational footprint:
    • Template to facilitate compliance footprint
    • Analysis of current footprint with energy and carbon hot-spotting advice

  • Detailed ESOS audit strategy:
    • Audit methodology, Assessor strategy, Data readiness
    • Specification of compliance plan and detailed budget
    • Full ESOS compliance audit by qualified Lead Energy Assessor
Average annual savings identified, with far more possible in certain industry sectors
Average annual energy cost savings identified, with far more possible in certain industry sectors

Our entry-point service

An entry-point service is also available for organisations who want to ensure that they are prepared for audit and compliance, comprising the following:

  • Web-delivered questionnaire for input data
  • Half-day, facilitated workshop
  • Readiness review, detailing:
    • Approach for compliance (including disaggregation)
    • Boundary definition
    • Audit reference period
    • High level view of Data readiness, Assessor strategy, Audit Methodology

This service pack is designed to allow organisations at all stages of energy maturity access to class-leading energy and carbon management expertise.

We also offer ISO 50001 advisory services for organisations wishing to achieve ISO 50001 certification.

Our dedicated in-house ESOS compliance team

We have a dedicated in-house ESOS compliance team comprising highly experienced Chartered Engineers, Chartered Energy Managers and ESOS accredited Lead Assessors. 

Since 2001 the Carbon Trust has:

  • Delivered over 35,000 energy assessments
  • Introduced £1.6bn worth of energy efficient equipment
  • Helped organisations save over £5.5 billion and reduce CO2e emissions by 60 million tonnes

Contact us to find out how our compliance team can help you:

call us on +44 (0)20 7170 7000, email us on, or fill in our contact form.

The Carbon Trust helped us to fully understand our ESOS options, and develop a plan to achieve compliance in the most efficient, cost-effective, value-maximising way.
Garry McDonald, Procurement & Sustainability Director, Miller Homes
ESOS Energy Savings Opportunity Scheme

The Carbon Trust Guide to ESOS

We recognise that many companies will need advice on how to comply with ESOS so we have compiled the Carbon Trust Guide to ESOS that provides practical advice and a summary of how the Carbon Trust can help.

The guide (updated October 2017) includes a step by step approach for Phase 2 compliance:

  • ESOS Background and policy aims
  • How will it affect my organisation?
  • How do I comply with the regulations? 
  • What are the benefits of ESOS to my business?
  • How can the Carbon Trust help?
  • ESOS Compliance Planning and Audit Strategy
  • Accessing the real value of ESOS
  • Appendix - Approved registers of lead assessors

Download the guide:

Full guidance on ESOS can be found on the GOV.UK website.


Beyond compliance

Simply complying with the Regulations misses the point of ESOS: to identify opportunities to reduce energy use and to cut consumption, emissions and cost accordingly.  Whilst there is no statutory requirement to take action on these opportunities, not to do so is to reduce ESOS to a costly compliance exercise rather than a means to achieve real savings. There are proven business benefits in addressing energy efficiency. Typically, 20% of a business' annual energy costs are wasted through the use of energy inefficient equipment.

A Guide to implementing Energy Savings Opportunities

The Guide to Implementing Energy Savings Opportunities has been developed to support businesses in implementing the energy saving opportunities identified from ESOS assessments.  Produced in collaboration with the Department for Energy and Climate Change.

It provides an overview of the steps businesses can take to maximise the impact of their ESOS assessment. It will help organisations follow best practice around the implementation of energy saving opportunities. This guide is particularly aimed at smaller ESOS participants, including those who may have less experience in implementing energy savings and/or may not employ a dedicated energy manager. However, the information in this guide may also be helpful to organisations with previous experience of implementing energy saving opportunities. It may also be helpful to organisations that have identified energy saving opportunities independently of ESOS.

Download the guide:

Get in touch to find out how we can help

We can help you comply with the ESOS regulations and go beyond to take advantage of the business opportunities to be gained from energy efficiency.   Act now to:

  • get maximum value from the compliance process
  • identify cost-effective energy efficiency opportunities to unlock financial savings
  • ensure high quality external support is available
  • prepare now to avoid challenges close to the Phase 2 deadline

To find out how we can help, call us on +44 (0)20 7170 7000, email us on, or fill in our contact form.


Our other services include:


Contact our ESOS compliance team today

Back to top