Conducting Effective Baseline Energy Assessments
With the second round of ESOS (Energy Savings Opportunity Scheme) recently announced and with more businesses deciding to seek certification to ISO 50001 - Energy Management Systems, I thought that it would be prudent to look at one clause in particular of the standard and one that is vital if continual improvement in energy performance is to be demonstrated.
ISO 50001 defines energy baseline as “quantitative reference(s) providing a basis for comparison of energy performance”. There are 3 additional notes:
An energy baseline reflects a specified period of time.
An energy baseline can be normalized using variables which affect energy use and/or consumption, e.g. production level, degree days (outdoor temperature), etc.
The energy baseline is also used for calculation of energy savings, as a reference before and after implementation of energy performance improvement actions.
At the simplest level the baseline could be the total amount of electricity and other fuels used in the year ending before the EnMS is implemented.
Another simple and often used baseline is to choose a measure of specific energy consumption such as kWh per unit of output. This has the advantage that it is simple and appears to offer the opportunity to compare with other similar organizations as a benchmark.
So, an energy baseline is a reference tool that allows you to compare energy performance before and after a change is made to your site or system and against which improvements will be judged. The baseline establishes the “before” by capturing a site or system’s total energy use prior to making improvements. It accounts for energy affecting factors like temperature or production volume.
So, now we know what a baseline is - how can we ensure that we carry this out in an effective manner and provide us with this accurate starting point we require for an effective energy management system?
A key part of implementing any management system is to finalize the scope that it covers. Therefore the first key part is to establish the boundaries of what is to be included. ISO 50001 does allow organizations the flexibility as to what is included within the system.
Choose a baseline year. I would always recommend any organization to choose the most recent year for which they have reliable and accurate data. This information may be in the form of energy bills, direct meter readings etc.
Look at the different forms of energy used. This is likely to include gas (piped and bottled), electricity, oil, wood and how/where they are used. The total amounts used in the set baseline year should be detailed. Do not forget any on-site generation such as solar PV, wind power etc.
Having established the total amounts of energy used in total, look at where each of these is used, decide on how best to break the usage down into smaller areas of usage. This may be individual buildings, groups of machines or individual processes. When actual measurement of data is not available, estimation of monthly energy consumption by power rating and operating hours may be adopted for the preparation of energy profile
Consider the key factors that can affect how energy is used. This may be for example weather related affecting amounts of energy used for heating/cooling, changes in production levels, shift patterns or customer requirements. These will be needed in order to work out performance indicators to be able to ‘normalize’ the data and take into account fluctuations that may or may not be in the organization’s control.
Remember, the aim of a baseline year is to set energy usage figures against which improvements can be compared.
One of the sometimes confusing elements of the baseline as required by ISO 50001 is the requirement for a flexible baseline. This may seem a contradiction in terms as baseline is usually a set or fixed period time and the data collected within that period. The standard requires that adjustments are made in the case of the following:
Performance indicators no longer reflect energy use and consumption
Major changes to the process, operational patterns or energy systems.
ISO 50001 is under review following the same pattern as ISO 9001 and ISO 14001. In the first draft of the revision, further information is given regarding the flexible baseline. According to the new draft, “When an energy use that consumes a significant amount of energy is removed or introduced within the scope and boundaries of the energy management system, the Baseline should also be modified accordingly”.
Therefore, to put this more simply, if any changes are made within the business affecting energy use, the baseline should be reflected to show how the changes would have appeared within that baseline year.
Finally, some guidance of performance indicators
The most common and simplest energy performance indicator is conformance to financial budgets. In many organizations this might be interpreted as successful energy management….it is not!
The overall purpose of the energy management system is to improve energy performance and to continually improve this performance. Ideally you will have at least one high level indicator for each energy source (electricity, fuel, etc) at the top level to indicate that overall you are in control. This is often very difficult depending on product and energy driver mix. You should also try to have an indicator for each of your significant energy uses.
It is important that you develop these indicators during this phase so that you can monitor them during the on-going data collection phase. The indicators may require modification once you start using them in order to improve their effectiveness in showing you how you are performing.
Author: Richard Walsh, NQA Environment & Energy Principal Assessor