James Brittain, Director of The Discovery Mill, returns to share some more insights on energy management. In the first of two features, he focuses on energy audits.


Having been the energy manager for London’s Heathrow Airport, I have had the chance to push boundaries and review what works well and what doesn't. While many organisations concentrate on using technology-based fixes, The Discovery Mill has shown that organisations can increase savings by integrating people into the solution alongside technical approaches.

To assess savings realistically, audits need to actively involve the people who use the buildings, which many audits do not. This article will offer some practical guidance on delivering energy audits through “your people” in a structured way.

Energy audits — the requirements

Energy audits are a big talking point at the moment, with the onset of mandatory audits imposed by the EU Energy Efficiency Directive and the UK's response through the proposed Energy Savings Opportunity Scheme (ESOS) for large organisations.

The standard BS EN 162471–1 sets out good practice industry principles for energy audits. A review, or audit, is an integral part of an ISO50001 Energy Management System (EnMS), being a good practice first step in any energy management programme cycle — the challenge is to make sure audit reports do not just “sit on the shelf” where their value is lost!

At Heathrow, we developed an EnMS that integrated the energy-auditing process into the implementation, planning and action tracking system. This approach centred on the facilities management (FM) teams across the airport and could be rolled-up at any time to “check” the strategic plan. Within three years of rolling audits, more than 800 action projects were included on the action tracker, led by a core group of 20 or so “key connector” energy champions, with around 40 to 50 individual projects being actioned at any one time.

This is a great way to identify and drive energy improvement on a local building level and on a large-scale basis at the same time. Overall, 15% savings (on average) were delivered across the airport during this period (2007-2010), with the best performing buildings realising more than 30% savings in electricity use, while improving building comfort and service in a “win-win” manner.


Audits are essential to check and enhance the performance of energy systems and the EnMS, to undertake due diligence for investment requirements, and to identify opportunities for improvements — ultimately, to help deliver the big vision for the estate, longer term.


The ESOS requires impartial specialist facilitation to oversee an audit. However, this is also a great opportunity to actively involve site key connectors — those staff who best understand the process and customer needs and, of course, those who control energy use.


An energy audit should be a systematic assessment of the EnMS approach, reviewing consumption and cost (we recommend doing this for periods of over a year) and concluding with recommendations for cost-effective, energy-saving actions.


From 2015, the ESOS will require an audit to be undertaken at least every four years. We believe a rolling programme of regular audits is most effective, surveying sites during periods of typical activity at different times of the year and operational practices.

The level of audit depends on the type and size of site, project goals and available budget. The outlook is typically three to five years ahead.

Level 1: Energy review — high-level audit

An energy review is the simplest type of audit. This often involves one-to-one interviews with key site personnel, an accompanied walk-around, review of site records (such as a building logbook, control parameters), and a high-level analysis of energy-consumption data — recommendations should focus on identifying which key connectors should be involved, as well as opportunities for management systems and energy-saving actions.

This may be the only level of audit used for a smaller site or to identify no/low-cost measures; otherwise it is often the first step of a more detailed audit — see Level 2. It is ideally done by the independent, fresh pair of eyes of an energy management consultant or in-house specialist.

Our “Four Ps” provide a key connector-centred framework for an energy review: Purpose, Practice, Projects and People.


The starting point, we believe, should be to review the strategic objectives and associated vision for the estate, corporate policy statements, energy performance indicators (EnPIs), audit/EnMS scope, boundaries and operational requirements.


Consumption and costs can then be considered in this context, in comparison with benchmarks and year-on-year performance. The review should identify the split across fuel types and energy demands, and the key influences on energy use.


A high-level action plan should be reviewed, giving an indication of savings potential, prioritisation and simple payback/return on investment (ROI) for different measures. An ISO50001 approach means driving ongoing, continuous improvement.


Once the key activities, practices and opportunities have been identified, the key connectors and energy champions to be involved can be targeted, and existing stakeholder engagement, committees, training and other initiatives can also be reviewed.

Involving people is often the lowest cost way of achieving savings, particularly on smaller sites. Not thinking about how to best involve your people at this stage can often lead to problems sustaining savings made. The UK is littered with technology fixes that are not delivering in practice.

Assessing savings from heating, ventilation and air conditioning (HVAC) retrofit measures, for example, needs to consider behavioural issues, such as “take-back” and “kick-back” at this level. Projects themselves may be delivered successfully, but any subsequent “kick-back” from operational teams will mean savings can be significantly undermined; we have seen savings even become negative when other linked, energy-saving controls are disabled. Any review needs to look for common feedback pitfall indicators: “Energy saving is not part of my day job”, “We’ve taken all the low-hanging fruit”, “Others write our action plans”, “Our fixes are all technical.” These all suggest there are behavioural issues to resolve.

Using our “Four Ps” allows us to present a strategic picture that gives a snapshot of everything that needs to be thought about, how it all fits together, with a clear line of sight to strategic objectives. This helps engage key connectors and provides the context for more detailed energy audits and associated project action plans.

Level 2: Survey audit — co-ordinated sweeps

A Level 2 audit is more detailed and is the opportunity to involve key connectors by asking them to put an energy hat on for surveys and sweeps within areas they know well. This allows you to dig deeper than ever before, bringing together ideas and issues within audit workshops and accompanied surveys (with technical specialists if required).

This level of audit is typically based on a snapshot (in time) and aims to focus on the key energy-consuming areas/asset types, and to rank specific energy improvement projects.

The Discovery Mill have developed a “CAPE” tool to help do this — it can be considered an energy audit equivalent of a Failure Mode and Effects Analysis (FMEA) for risk assessments. Prioritisation is centred on energy savings ROI, using the client’s investment criteria, but it can also factor in a measure of best overall value, for each proposed remedial measure, by scoring the benefits for customers, assets, performance and energy.


Most survey audits include snapshot environmental measurements, but the best way of evaluating lighting, air quality, temperature, ventilation and other working environment issues is by asking the users themselves through feedback interviews, questionnaires or workshops, to help assess and improve comfort in a structured way.


Sketch and check the type and condition of the building, building services and energy-consuming equipment (layout, age, quality, controls, operation and maintenance provisions, and monitoring). We categorise energy-improvement projects with asset types (or renewable/management opportunities) to help track asset investment.


This means energy-efficiency practice in use and usually relies on an auditor’s intuition (and industry benchmarks) to assess, but this can be scored in a structured way using the knowledge of local staff (about behaviours, operating and maintenance practice, and space/process utilisation) supplemented by zoned environmental measurements taken.


No/low-cost measures are often “no brainers”, but more complex ROI calculations rely on supplier quotes. Once this desk work has been done, projects can be prioritised in terms of impact and ease of implementation — this is often done best within a workshop to ensure all operational and behavioural issues are properly thought through.

An NHS hospital trust used a CAPE approach to target hotspots for its new programme of energy projects. With four hospitals, it wanted to review the impact of key opportunities both on an energy-savings ROI basis, and on overall positive value. To enable this, we surveyed hospital staff across all the buildings, asking for feedback on their working environment. Buildings and areas that had negative user feedback, poor assets, poor performance practice and were quick return energy projects were prioritised first. This proved to be a great “win-win” way to engage key connectors in energy projects and build some good momentum for their carbon management plan.

CAPE is an example of a way to facilitate audits, drawing on your local key connector expertise and on outside expertise to help pull it together if required. This gives a whole building approach that can be applied to energy audits or focused surveys, for example to comply with the EU’s requirement for regular air-conditioning inspections.

Level 3: Investment grade audit — monitoring and impact simulation

Once Level 1 and 2 audits have been completed, more detailed investigations may be necessary to make it “investment grade”, if significant roll-out finance is required. Decisions may need to be based on more accurate verification monitoring of sample/trial areas, and simulated energy performance and financial models. This typically takes a number of months to complete.

At the hospital trust, proposed lighting and motor controls solutions were trialled with verification monitoring put in place — not only to enable the trust to sign off investment proposals, but also to secure any third-party financing arrangements as required.

At Heathrow, the comprehensive proposed capital investment plan and predicted benefits were regularly reviewed in the energy model to simulate ROIs, and then feed into rolling, five-year budgeting forecasts and longer-term CO2 emissions projections — this satisfied internal governance and reputational drivers for the airport’s licence to operate.

The strategy for permanent verification metering and monitoring should be designed to demonstrate value for money, post-completion, and ensure that controls are locked-in to provide continuous improvement and confidence that you are only using what you need.

Energy audits through people

The level and detail of the audit used should be appropriate, representative, traceable, useful and verifiable.

In reality, as they are predominantly technical, there is a risk with many audits that the estimated savings will not always be achieved in practice, or recommendations will not offer the best overall value, as their behavioural initiatives do not go far enough. They need to recognise that energy efficiency is an operational and behavioural issue for most organisations.

When undertaken “through people”, audits can go further than other approaches by including more local involvement to help target the best opportunities, by making a more realistic assessment of longer-term savings and by bringing together the technical, behavioural and operational aspects of change.

To deliver this, audits can be conducted in partnership with staff and teams, with key connectors providing the expert legwork “on the ground”, typically with a consultant applying an independent, fresh pair of eyes to draw it together and make the key recommendations. In this way, bigger savings are also often identified in a much more efficient and cost-effective way.

Ultimate success means you are left with a shared vision and action plan for delivering continuous energy improvement and a better estate all round — cutting costs, pruning environmental impact, and delivering better service and value for your customers.

Last reviewed 10 February 2014