Produced in Association with SERIES 22 / Module 02 Measurement & Verification
then calibrated against actual building energy use once data is available. These simulations can be run with and without EEMs in order to estimate their impact. The advantage of this approach
is that it allows for evaluation in the absence of building energy data (e.g. for new buildings), but should note that the evaluation of energy savings will be based on the calculations used in the simulation software, unlike the in-situ measurements used for the other IPMVP approaches.
What are 'adjustments'? 'Adjustments' have been referenced in this article and are often used in M&V, so what is meant by them and why are they relevant? It is worth first noting that there are two general types of adjustment – ‘routine‘ and ‘non-routine‘ as follows. Routine adjustments These
describe changes made to baseline or reporting period data to account for expected changes in energy consumption or demand. For example, as external temperature becomes colder, heating fuel consumption would be expected to increase, or if a manufacturing facility produces less, its consumption would be expected to reduce. Weather and production are examples of 'independent variables' – these influence energy consumption and for a fair comparison with and without EEMs they should be taken into account. As noted under the Option C description, this is often achieved by developing a mathematical model using regression analysis, allowing statistical metrics to validate the model and provide information about how well variation in energy data is explained by independent variables. Non-routine adjustments These
describe unexpected changes within a measurement boundary resulting from changes in aspects of a facility that would usually remain static. For example, building floor space/area, primary use, material changes in plant and equipment. Such changes will need to be taken into account and their value estimated – this is often achieved via an engineering calculation specific to the change identified. Such changes can present a challenge
for M&V, especially if they are not well monitored as this can lead to a lack of good information and potentially disagreement between interested parties. Outlining a process for capturing and calculating non-routine adjustments is important for M&V, particularly to enable transparency in the savings reporting.
Energy consumption modelling for electricity – actual data against the ‘adjusted’ baseline model
Example Site - Electricity -Model vs Actual
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Dealing with uncertainty M&V addresses the challenge of uncertainty – it is important to consider whether a proposed method will yield sufficiently low uncertainty that the expected savings can actually be measured. An outline of the key sources of uncertainty are as follows: Modelling – mathematical models
are often used in M&V to quantify relationships between independent variables (weather, production, etc) and energy consumption. The statistical technique of regression analysis allows
M&V practitioners to do this and to understand the error associated with their models. Metering – devices used to measure
energy, power, or other key parameters and variables will have some error in terms of their precision and accuracy, details of which should be available from the meter’s manufacturer. Note that under IPMVP, utility meters can be considered 100% accurate for M&V purposes since the measured consumption is directly related to billing cost. Sampling – when similar EEMs are
Measurement boundaries for M&V – whole site and example isolated measurement boundaries
Professional Qualifi cations To enable the recognition and to develop the expertise of energy professionals involved in Measurement & Verification, the ’M&V Fundamentals and IPMVP’ course leading to the ’Certified Measurement & Verification Professional’ (CMVP) was jointly developed by the Efficiency Valuation Organization (EVO, who own the IPMVP) and the Association of Energy Engineers (AEE). This course has run in various locations worldwide for well over a decade and continues to be run by the AEE. In 2022, EVO created two new
certifications, which, following their global survey of 2019, reflect industry wide interest in the further enhancement of the knowledge and skills of M&V Professionals. The Performance Measurement & Verification Analyst (PMVA) certification is EVO’s programme for M&V fundamentals, whilst the Performance Measurement & Verification Expert (PMVE) certification establishes an advanced level qualification in IPMVP and M&V to distinguish individuals who are regularly involved in preparing or assessing M&V Plans.
Summary A well-structured M&V process brings transparency to reported savings, providing clear evidence of energy and carbon reductions and supports the risk management of performance-based contracts. It also allows for continuous improvement – the activity of measuring savings accurately identifies areas where there may be shortfalls and opportunities for rectification, as well as further energy efficiency improvements. In summary, M&V is intended to verify the effectiveness of energy and carbon saving initiatives, to ensure accountability and support sustainable energy management. ▀
Pre Project kWh Post Project kWh Commissioning kWh Baseline Model kWh
deployed multiple times – light fittings for example – a sampling approach is often used as a way of reducing measurement cost, but consideration should be given when doing this so that the uncertainty doesn’t increase outside of acceptable limits. Following a structured M&V process
means that each of these sources of uncertainty will be considered and can be evaluated relative to the value of the energy savings. Where uncertainty is considered too high, this may result in alternative M&V approaches to be taken, but ultimately assessment of uncertainty should help all parties in understanding the underlying measurement risk.
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