In this article Alan Field explores the implications of implementing an Energy Management System and integrating it, to a greater or lesser extent, with an Environmental Management System. Whilst for some organisations the minimisation of energy is not a key part of their EMS, this article explains why this is something that might be reconsidered to their advantage.

Environmental management systems (EMS), particularly those following ISO 14001:2015 principles, are now commonplace in many sectors. Being “green” is no longer a fringe interest, as both consumers and business-to-business customers now expect to deal with organisations who are perceived as having sustainable credentials.

An Energy Management System (EnMS) can have a number of definitions but, broadly, it is a systematic approach to identifying, analysing and managing energy usage and how this can be minimised. In some organisations this means there is a level of process improvement that is required in terms of energy resources i.e. reducing the need for energy in that process and this is the ideal outcome. However, many an EnMS will simply focus on the more efficient use of energy supporting current processes. In other words, identifying actual energy use within the organisation and then identifying better ways to deploy it. In an EMS, an organisation is looking for better ways to deploy resources to minimise their impact on the environment and energy can be part of that. More importantly, a key part of an EMS is key is monitoring the organisation’s controls over their carbon footprint and energy is always, to a greater or lesser extent, part of that.

What are the differences and similarities between an EnMS and EMS

Both ISO 14001:2015 (EMS) and ISO 50001:2018 (EnMS) follow the International Organization for Standardization’s (ISO) High Level Structure (HLS), so areas such as risk-based and leadership-managed processes are common to both ISO 14001 and ISO 50001. Whether one is seeking external assessment for either or both standards, these common factors can lead to integration between them and, indeed between other ISOs which follow the same HSL structure. This means that there can be one set of policies, and risk and opportunities based objectives, and thus economies of scale.

But there are also significant differences between ISO 14001 and ISO 50001. ISO 14001 is a more generalist standard in terms of environmental management – a leadership team need to decide what the key risks and opportunities are in relation to environmental management within their organisation. In some sectors, the priorities might centre around energy but in others it might be waste or pollution that are more directly relevant. ISO 50001 is very much about energy management – not just about the risks of consumption but identifying areas of opportunity to have access to better metrics in relation to wider issues of resource management.

An EnMS can of course be managed separately from an EMS, sometimes because of differing managerial responsibilities for the two systems e.g. there may be a separate Facilities Manager and an Environmental Manager. Where there is an integration of management systems it is essential that there is leadership commitment – this doesn’t necessarily mean that the same Board Director is ultimately accountable for what the two managers do but the Board would need to set an agreed plan or approach to the whole of the EMS, including energy. For example, are there risks and opportunities that cover both energy and environment?

Even if energy is not the main environmental impact almost all businesses will consume energy and there will therefore still be a risk of higher carbon impacts. There may opportunities to identify where energy is consumed in various stages of a process. An EnMS will achieve this through more specific processes not necessarily required within an EMS.

Another potential reason for integrating an EMS and EnMS might be corporate responsibility (CR) policies. Some organisations may separate their CR from other management systems, but other organisations will see matters such as minimising the use of plastics or reducing energy consumption requiring fossil fuels as supporting CR. There can be a direct link to environmental and energy management, certainly at policy level if not with more operational processes. In other words, an EnMS can support CR initiatives in a very similar way to how an EMS does.

If ISO 50001 principles are adopted by an organisation, this requires a documented Energy Review (see ISO 50001 toolkit). This is an analysis of energy use and energy efficiency and will be based on usage data and any other relevant information. This enables areas of significant energy use (SEU) to be defined, and these may identify potential opportunities for energy performance improvement.

Once the SEUs are identified more detailed analysis can be undertaken. This may be examining energy bills (and perhaps even installing more sub-metering) or ensuring building management systems (BMS) are generating useful reports, for example, is electricity being consumed at 3 a.m. when the office is closed? It is also a process for ensuring that variables are being identified e.g. air conditioning will use more energy in the hot weather; where there is production machinery or even in a warehouse operation there may be peak times of production or product testing that would explain energy spikes.

As can be seen, without defining SEUs then these type of investigations and analysis would not take place. At the same time, they in no way conflict with an EMS.

Finally, the initial Energy Review, with the SEUs, all data and any variables obtained, then feed into an Energy Baseline. The Energy Baseline provides a starting point or base metrics to measure all future improvements in energy consumption or other energy management improvements.

It can be seen that such metrics align with an EMS; they relate to an organisation’s impact on the environment. Just as one example, less fossil fuel being used to generate electricity means a reduced carbon impact, so any reduction in energy demand within the organisation supports the EMS and EnMS.

Integrating management systems may need some thought and extra implementation time but, as can be seen, with the aligned support of top management the EMS and EnMS can be more efficient in themselves as well as bringing more energy efficiency to an organisation and thus reducing its impact on the environment.


  • Energy management systems provide a systematic approach to identifying and minimising energy usage within an organisation on an ongoing basis

  • While an environmental management system might not always explicitly consider energy as much as an EnMS, there are many synergies that can be obtained by integrating the two approaches

  • Integrating an EMS with an EnMS can lead to economies of scale and other advantages rather than running two separate management systems

  • Many organisations will achieve at least some energy efficiency by undertaking an Energy Review

  • In turn, the Energy Review will lead to areas of Significant Energy Use being identified. These areas of SEUs will help an organisation monitor and measure energy usage in specific areas and identify variables

  • This then leads to an organisation defining its Energy Baseline from its initial Energy Review

  • All these approaches support an EMS — reduction in energy usage or smarter use of energy impact on an organisation’s carbon footprint — SEUs and baselines all provide an ongoing model to properly determine the carbon footprint and any improvements achieved.

For more detail on putting an Energy Management System in place see our Energy Management and ISO 50001 topics. For more detail on Environmental Management Systems see our EMS Standards, and ISO 140001 topics.

Last reviewed 23 July 2019