Q: I would like to confirm the IPMVP Option that best aligns with our M&V approach. We provide fully financed, turnkey energy efficiency solutions to our commercial and industrial customers. These solutions can be deployed as either portfolio programs across multiple sites throughout the US or single site projects. We bill our customers based on the post-install energy savings for each "system" we install at a given site, where a "system" in our contracts is defined as the all of the equipment we install, retrofit, or optimize at a given customer site (e.g., replacement chillers, boilers, pumps, and air handling units installed at a single site can constitute a "system" in our contracts). For each contract "system", we install submeters to monitor and track the energy use of the equipment included in that "system" both before and after that equipment is optimized, retrofitted, or replaced. The pre-install metering period can vary system to system based on a variety of factors including the what equipment will be addressed and how local climate and/or site operations impact the energy use of that equipment. To measure the energy savings, we aggregate the post-install submeter interval data for the "system" and compare it to the baseline regression model established using OpenEEmeter and the pre-install submeter data. Internally, we have interpreted our M&V approach as Option C because we measuring savings at the whole building level using our submeter interval data to isolate the contract "system" from the rest of the energy using equipment at a given customer site. Is this interpretation correct? If not, which IPMVP Option best aligns with our standard M&V approach?

A: Based on the above description of your M&V strategy, since you are describing the measurement boundary for the sub-meters at the EEM equipment specific level, ("using our submeter interval data to isolate the contract "system" from the rest of the energy using equipment at a given customer site"), this approach would conceptually align with an IPMVP Option B Retrofit Isolation approach - assuming all parameters are being measured.
Please refer to the current IPMVP Core Concepts Chapter 8 for more guidance in selecting IPMVP Options as well as Chapter 9.2 regarding Option B applications and methodology.