Leading an ESOS Assessment

Topic Sustainability

CPD Hours 7


In July 2014, the Department of Energy and Climate Change (DECC) introduced a new regulation, Energy Savings Opportunity Scheme (ESOS). This regulation required all large enterprises to carry out an ESOS compliant energy assessment by 5 December 2015 and then every four years thereafter.

Phase 2 of the ESOS regulation is now underway and all qualifying organisations are now able to begin the compliance process, with assessments needed to be completed by 5 December 2019.

These audits can only be conducted by an approved ESOS Lead Energy Assessor and IChemE has been named as an approved authority to award this status. This course provides participants experienced in energy assessment with knowledge to lead, review and approve an ESOS energy assessment. It uses the fundamentals of ISO 50002 and PAS 51215 as a basis. 

This course is a prerequisite to registration as a ESOS Lead Energy Assessor with IChemE.

Please view the benefits of becoming a qualified ESOS Lead Energy Assessor.

Course outcomes

Upon completion of the course, participants will have gained a thorough knowledge of:

  • the processes of leading, reviewing and approving an energy assessment according to ESOS and PAS 51215 (see additional core competency information)
  • the competency requirements of lead energy assessor according to PAS 51215
  • using data analysis as a basis to scope the energy assessment and to inform opportunities of improvement
  • the common variables that changes energy consumption
  • applying systems thinking in energy assessment.

A post-course assessment will have to be completed and passed by delegates within 7 days of the course, in order to become registered as an ESOS Lead Energy Assessor.

Who will benefit

Those that wish to become a registered ESOS Lead Energy Assessor in order to provide energy audits for their company or who wish to become registered in order to undertake external consulting work.  

Criteria for admission

The minimum requirements for admission are:

  • Chartered Membership (MIChemE) or Fellow (FIChemE) of Institution of Chemical Engineers
  • experience in carrying out energy management and energy auditing activities (typically no less than 5 years).


In order to register for this course you must fill out a course experience form. Please click here to download the form.

This form must be returned to or faxed to +44(0) 1788 560833.

We will be able to confirm your acceptance on the course within 5 working days.


  • IChemE member: £850.00 + VAT*
  • Non-member: £1000 + VAT*

*If delegates successfully pass the post-course assessment, there will be an additional £100.00 annual fee, in order to be added to the ESOS Register.

Course outline


  • Why carry out and energy assessment
  • Energy use in buildings and industry
  • Key definitions
  • Approaches to energy assessment

Planning for an energy assessment

  • Boundary of ESOS energy assessment
  • Scope of ESOS assessment
  • Output of ESOS assessment
  • Reporting ESOS findings
  • Enforcement

Process of carrying out an energy audit

  • The difference between and energy 'audit' and an 'assessment'
  • Steps in an energy audit

Competencies for energy audit

  • Leading an energy audit
  • Energy audit team competency
  • Choosing a competent energy auditor
  • Becoming an ESOS lead assessor

Analysing energy data

  • Sources of energy data
  • Material and energy balance as a source of data
  • Known energy variables
  • Relationships of energy data and known energy variable
  • Energy performance indicators
  • Benchmarks
  • Flaw of averages

Opportunities for improvement

  • Sources of inefficiencies
  • Rules of thumbs for checking calculations
  • Identifying with opportunities for improvement


  • Maximising energy savings
  • Quantifying non-energy savings
  • Quantifying the cost for improvement
  • Valuing opportunities (SPB, NPV, IRR, life cycles, etc.)
  • Prioritising opportunities for improvement
  • Methods to monitor and verify of energy savings

Energy audit reporting

  • Document control
  • Dommunicating energy savings

The course utilises a series of short lectures, classroom discussions, video clips and examples from commerce and industry, allowing participants to critically analyse, assess and define the aspects of leading, reviewing and approving an energy assessment in their current and future employment.

Background reading

  • British Standards Institute. 2014. ISO 50002 Energy audits -- Requirements with guidance for use. BSI Publishing
  • British Standards Institute. 2014. PAS 51215 Energy efficiency assessment – Competence of a lead energy assessor – Specification. BSI Publishing
  • David McKay. 2008. Sustainable Energy – Without Hot Air. UIT Cambridge
  • Vilnis Vesma. 2011. Energy Management Principles and Practice.2nd Edition. BSI Publishing
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