How much did it save? Why good Measurement & Verification accelerates energy efficiency
Many organisations go full steam ahead with energy efficiency projects without giving proper consideration to the measurement and verification (M&V) of actual savings. Later, when the CFO asks what his/her investment has achieved, the books do not always tell the same story as the energy savings forecast.
This is partly due to a common misconception that calculating project savings is a simple case of consumption pre-installation less consumption post-installation. In reality savings should be determined by calculating what the consumption would have been without the project implementation, less the consumption post-installation. This subtle difference can cause no end of problems if not clearly understood by all stakeholders prior to the project kick off.
It is therefore very important that good quality appropriate M&V is considered before project inception.
What is M&V and more importantly what is good quality M&V?
The M in M&V is Measurement, which is the quantification of something, usually established by using some form of instrumentation. Measurement of savings however requires careful consideration because it is the quantification of the absence of something; usually avoided energy consumption. Therefore savings cannot be measured in the traditional sense and this is where the art of good M&V comes into the equation.
Measuring the baseline consumption is very important, but equally important is recording the circumstances in which this consumption took place; was it during winter months, what were the operating hours, what setpoints were in place and the list goes on. If all these factors are not established then comparing the consumption after the project will more than likely give inaccurate savings figures. The introduction of a good quality M&V Plan at design stage sets clear strategies on how savings will be calculated against established baseline conditions, enabling true savings to be ascertained.
The V in M&V is Verification and should be carried out in two senses:
- Operational verification - the verification of the installation itself and the savings achieved
- and the Verification of continued performance
By checking that all designed parameters are being delivered by the new installation, organisations can have increased confidence when signing off practical completion that their energy conservation measures can deliver savings for the asset life. Good operational verification can also provide a check-point to ensure operational personnel fully understand how to run and maintain the new installation efficiently.
Whether the M&V strategy is based on the widely used International Performance Measurement and Verification Protocol (the IPMVP®) or the more recently introduced ISO 50015, the terminology used in the M&V plan and savings reports should be clear, consistent and easily understood by all stakeholders. Baseline consumption, static factors, independent variables and the significant energy consumers, along with concise specifics of energy and cost savings calculations should all be documented, explained and agreed prior to the implementation of the project. This is particularly important where projects are trials for a replication strategy, as future business cases should then be built on an un-biased review of the facts.
SMS offer third party M&V services carried out by certified measurement and verification professionals (CMVP) accredited by the AEE. Where appropriate SMS can provide instrumentation for short-term monitoring or deliver sub-metering networks to support the transparent determination of energy savings.
We believe it is crucial to set out an M&V strategy at an early stage of any energy savings project, therefore SMS are offering free technical consultation on proposed energy savings projects in order to establish their bespoke M&V requirements.