I can’t keep saying that every process of energy management is important, so maybe the whole process is important as it all has its place in the process. When it comes to Measurement and Verification, I have always ensured I focus on making sure what I have consulted on will make the savings I have forecasted. Now this can be quite straight forward if nothing changes within the building environment.
I want to emphasise why it is critical to actually demonstrate that a project has made a saving, because for me if a energy management project has not delivered the desired impact then I as the energy consultant have made a mistake. I always remember when I was just starting out in my career in Energy Management and we had installed a building management system within a building and my manager at the time was accused of just installing this system and walking away.
This statement was half right, however my manager then went on to present the significant savings that had been made and the savings it was currently making on the day. To provide good measurement and verification you must have good data. Now that data must be not only energy data, but it must be weather related data and possible some form of volume metric whether that is sales of attendance. If you have this data prior to the implementation, then you are in a good position to start to verify. My only advice here is that you ensure that your verification follows the same pattern and you do not change the way you measure.
Once the measuring process has been agreed with the organisation it is worthwhile at this stage to provide a written methodology explaining the process of how you intend to verify the project.
Why introduce volume metrics into your measurement? The reason for introducing this is because buildings may change, the occupancy may change, the external temperatures may change, and sales volumes may change. All this data creates a benchmark on your energy consumption.
- Buildings may change – The organisation may extended the building
- The occupancy may change – There may be an increase or decrease in staff
- The external temperatures may change – Freak weather changes from measured points
- Sales volumes may change – up or down
Benchmark = Energy kWh / Volume Metric
Simply by measuring these values you will understand what your benchmark is before the project implementation and after.
Then by looking at these two Benchmarks …
Previous Benchmark – Current Benchmark / Previous Benchmark = % savings calculated.
Admittedly, this is making this point very simplified, but I wanted to show how we can demonstrate this.
I personally like to use scatter graphs on MS EXCEL and then apply straight line graphs. This then leads you into ‘Simultaneous’ Equations (Blast from the past from the college days) but please do not be scared of the maths, because MS EXCEL does the work for you here.
Over the years I have always followed the ‘Measurement and Verification’ process, because it really does prove that the project and the technology does work. I have spent some time with technology experts on a boiler system and when we first installed the project, it did not actually work. We had to carry out a full review on site to understand exactly what was happening. Because we had set our measurement up on a Day+1 basis we were able to prove the savings the next day.
For me proving the implementation must be done with agreed measurement and not through the bills but through the meter. I have discussed before we do not know what in accuracies are within the bills and what periods we are going to compare. For me through the meter is the best way whether it is on monthly meter readings or using interval data from the ‘Data Collector’.
If you are looking at implementing a strategy or looking to implement an energy management program now is the time to start to collect your data from meter readings or interval data. One of my clients I work with has data going back to 2016 you will be surprised how often I look back at this data.