If your organisation is undertaking an energy efficiency project and hasn’t been given a plan for how energy savings will be measured, consider this; would the project go ahead if there were no energy savings associated with it? When investing in energy efficiency, a Measurement & Verification (M&V) Plan outlines the method for proving the performance of the investment.
However, there is a fundamental difference between investing in energy efficiency and typical investing, even in renewable energy. When investing in solar we measure how much electricity is produced, which is then converted into a dollar amount. For energy efficiency, energy savings are measured. An energy saving is the absence of energy being used. So, how do you measure how much energy is absent?
Comparing Utility Bills
The simplest consideration is looking at two utility bills, one from before and one from after implementing an energy efficiency project. Compare how much electricity or gas was used in each case, the difference is the savings achieved. Easy! However, this approach is far too simple. If the first bill was for summer and the second for winter, then this may not be a fair comparison. Likewise, if in the first period a building was only half occupied and in the second period fully occupied.
So, there’s a need to understand what influences energy use in the first place. Weather, occupancy and production levels, among other factors, can all impact usage. The trick is to find which of these factors has a relationship with energy consumption and determine how statistically significant this relationship is. Unfortunately, the ‘simplicity’ of comparing utility bills has well and truly departed and we are now into some heavy, specialised, statistical analysis. But fear not, there is good news ahead.
Industry Protocol and Certification
Understanding that M&V is a specialist skill, the energy efficiency industry has developed a ‘protocol’ and professional certification to help create uniformity and certainty in measuring energy savings. The tongue-twisting International Performance Measurement and Verification Protocol (IPMVP) and the more pleasantly named Certified Measurement & Verification Professional (CMVP). Experts with the CMVP accreditation have undertaken an examination and certification process to validate their knowledge and experience in M&V.
|Option A - Retrofit Isolation (Single Parameter)||A Single, Key Parameter is measured, either shortterm or continuously
Example: Measuring instantaneous lighting power draw pre & post upgrade but stipulating (not measuring) the hours of operation
|Option B - Retrofit Isolation (All Parameters)||All Parameters are measured, either shortterm or continuously
Example: Measuring the consumption of an air conditioning unit pre & post upgrade
|Option C - Whole Facility||Entire facility consumption is measured pre & post an upgrade. May be shortterm or continuous measurement.
Example: For a major building upgrade, its easier to measure the whole building consumption rather than individual systems. Accounts for interaction between efficiency measures.
|Option D - Calibrated Simulation||Savings are simulated via an energy model which is validated against actual performance. Requires significant experience and skill.
Example: New construction with energy efficient enhancements.
Your energy efficiency provider should be well versed in IPMVP and will be able to justify the selection of M&V option. Ensure that a Certified Measurement & Verification Professional develops your M&V plan, the industry has accredited these professionals to accurately measure energy savings.
Another key concept to understand is Baseline Adjustments. Baseline adjustments are applied to savings calculations to account for variations outside of the energy efficiency providers' control. They come in two flavours, routine and non-routine.
A routine adjustment accounts for variations that are highly likely to occur, and a 'routine', or method, is in place to incorporate them into the energy savings. For example, if your energy consumption is highly dependent on the weather, which is highly variable, the energy efficiency provider should have a routine for adjusting the savings calculations within the M&V plan to account for weather.
Non-routine baseline adjustments may occur due to unforeseen changes to a facility. For example, if a building is extended or an office is converted into a data centre. Energy efficiency provider's are within their rights to adjust the baseline to account for such variations which are beyond their control.
When reviewing M&V plans, at a minimum, ensure they comply with IPMVP. A note of caution, IPMVP is not a standard, it provides general, not prescriptive, guidelines to follow. For a thorough review, consult an independent CMVP prior to engaging your energy efficiency supplier.
Remember, no Measurement & Verification plan =
No Return on Investment
This post is a snippet from our two-part guide that will help you achieve your sustainability goals through energy efficiency upgrades.