MEASUREMENT AND VERIFICATION (M&V): CONCEPT AND APPROACH FOR DETERMINING ENERGY SAVINGS

 

Energy saving in Malaysia is an important aspect of the country's sustainable development initiatives. With increasing energy demand driven to industrialization and urbanization, the Malaysian government has made energy efficiency a top priority. In line with this, the Malaysian government has introduced Energy Conservation Measures (ECM) projects, aimed specifically at reducing energy consumption in buildings. To accurately assess the impact of these projects, Measurement and Verification (M&V) activities were introduced. M&V is a process that uses measurements to reliably quantify the actual savings generated by specific actions under an energy management program.  Although M&V implementation in Malaysia is still relatively new, it is critical for ensuring accuracy and managing uncertainty in baseline energy modelling and savings reports. This accuracy is especially important when the savings are used as a basis to justify the return on investment for energy savings projects.

Several protocols and guidelines have been established for determining and verifying energy savings, with the International Performance Measurement and Verification Protocol (IPMVP) being the most comprehensive and widely adopted. The IPMVP, developed by the Efficiency Valuation Organization, provides a complete framework for M&V projects and has been applied to various energy efficiency measures worldwide. The key principles of the IPMVP for reporting energy savings are to ensure accuracy, completeness, consistency, relevance, and transparency. The IPMVP provides four measurement options to evaluate the savings [1] according to their area of application, namely; Option A, B, C and D where,

Option	Description
Option A	Key Parameter Measurement Retrofit Isolation. To determine the energy savings at retrofit point, where at least one parameter needs to be measured and others can be estimated using the building’s history or the manufacturer’s specifications.
Option B	All Parameter Measurements Retrofit Isolation. To determine the energy savings at retrofit point, where all parameters need to be measured. No estimations are allowed for this option.
Option C	Whole Facility. To determine the energy savings; where energy use for the whole or sub facility needs to be measured. Usually, energy data for this option is obtained from the electricity bills calculated using the energy suppliers’ meters
Option D	Calibrated Simulation. To determine the energy savings; where energy use for the whole or sub facility or retrofitted point is determined using energy simulation software.

Since energy savings cannot be measured directly, they are determined by comparing energy use before and after the implementation of an ECM. The figure below illustrates the M&V conceptual framework, which visualizes energy use during the baseline and post-retrofit periods, as well as the process for determining energy savings.

M&V Conceptual Framework

To accurately report savings, the baseline energy use pattern (before ECM implementation) is analysed to establish the relationship between energy use and independent variables. According to the IPMVP, in order to properly determine savings using M&V, a baseline energy model must first be developed using regression analysis to identify the relationship between energy use and independent variables. An independent variable is any factor that affects energy use in a building and is expected to vary, such as weather conditions, occupancy, or production levels. A baseline energy model is considered valid for determining savings if it meets the statistical correlation criteria specified by the IPMVP. After ECM implementation, this baseline energy model is used to estimate how much energy would have been used if the ECM had not been implemented. This estimate is referred to as the adjusted baseline energy. Savings are then calculated as the difference between the adjusted baseline energy and the energy measured during the post-retrofit period. If the baseline energy model meets the correlation criteria specified by the IPMVP, it is considered acceptable for reporting energy savings. The smaller the error in the baseline model, the more accurate the reported energy savings will be.

[1]      Efficiency Valuation Organization, “International Performance Measurement and Verification Protocol (IPMVP),” 2012.

Prepared by:

Dr Wan Nazirah Wan Md Adnan

Dr Anis Sabirin Baharom