CS 2009 EAc5.1: Measurement and Verification—Base Building

Your question covers a lot of issues, but in general the intent of M&V is to ensure that the building is performing as projected/expected. This inherently means that there must be performance projections, usually in the form of energy simulations. (Otherwise, how do we determine which design strategies are effective and which are more in the realm of wishful thinking?) While LEED and/or ASHRAE impose certain parameters on the process of comparing the performance of a Proposed building to a baseline, the form of the Proposed building simulation for the purposes of M&V is really not constrained by these parameters. In fact, it could be argued that it shouldn't be if the primary objective is to truly validate the projected performance of the Proposed. So, while it is true that ALL energy simulation software packages suffer from limitations to varying degrees, it is usually possible to develop "workarounds" for many of the issues. Often it is simply a matter of devising creative ways to model a condition using the basic capabilities of the software e.g. scheduling ventilation to mimic DCV based on expected occupancy. At the other end of the scale it may be necessary to develop custom simulation functions or combine simulation tools, such using the output from a specialized CFD analysis to schedule space conditions in a more mainstream simulation package. And, bear in mind that many apparent software limitations turn out to be inconsequential if fully considered from a first-principles perspective - which in many instances is why the "feature" was left out of the software in the first place. While energy modeling will never be perfect, in my experience very seldom is it impossible, one way or another, to generate results that are a defensible projection of building performance.

BTW, the 25% process load in LEED is only a default. You are entirely free to use a higher or lower value provided that it can be justified.

Looking through the IPMVPThe International Performance Measurement and Verification Protocol (IPMVP) provides best-practice protocol for measurement and verification of new construction. This standard is referenced in LEED's measurement and verification credits. document it appears that credit EA 5.1 has nothing to do with the energy modelling required in EAP2/C1. Under option D: Calibrated Simulation, it talks about comparing a baseline energy model (which is autosized) and based on a real weather data file over the M&V period, with an 'as built' energy model with actual design capacities/values etc and then comparing the both of them to actual metered readings. Is this correct? If so, then you do not need to enter in any energy use information into the 5.1 submittal for C&S and New Construction projects because the project is not monitored yet. Is this correct? or have i missed something here? thanks in advance

EAc5.1 does in fact start with the energy models produced for EAp2/c1. The Proposed model as submitted for certification should represent the as-built building. The model is then calibrated through the M&V process as described in my response below to Robin Williams Heeks. With respect to providing the actual energy use as part of the EAc5.1 submission, you are correct - that is simply an error in the on-line form.

Re: Calibration to actual energy use??

Without knowing exactly where you are looking in the reference guide, I believe the intent of the word "calibrate" is to coordinate the design of your project's metering system / Measurement and Verification Plan with your energy simulation model. In other words, if your energy simulation measures plug loads and lighting loads separately, these values should also be tracked separately in the actual building's metering design - so the design intentA written document that details the ideas, concepts, and criteria that are determined by the owner to be important to the success of the project. can be verified. As regards the "as-built" language, can you provide a page reference?

"Calibration" means adjusting the independent variables in the energy model to suit actual conditions. This includes variables like weather, hours of occupany, occupancy densities, and equipment/system operational schedules. After these adjustments are made the model is re-run, and the calibrated results are compared to the actual energy use of the building over the one-year M&V period. This comparison occurs at the system as well as whole-building level. Significant deviations between the actual and projected energy use are then investigated and reconciled/resolved. While properly conducted energy modeling can be surprisingly accurate, it is not perfect and some deviations can be expected. My guidelines for what constitutes acceptable correlation are as follows:

+/- 10% for total annual energy use
+/- 10% for total annual energy use for each energy source
+/- 15% for total monthly energy use
+/- 15% for monthly energy use for each energy source for any month with use higher than 30% of the peak month
+/- 15% for end-uses on an annual basis
+/- 15% for end-uses on a monthly basis for any month with use higher than 30% of the peak month

I hope this helps.....

Yes, thank you very much, it is clear now. So if I understand correctly, if you have just one meter for the whole building and you have a properly planned M&V plan, and you compare the calibrated energy model with the actual annual consumption you are eligible to earn this credit under Option D, right?

Uh, no. While it could be argued that whole-building meters are sufficient for very small buildings, any building of significant size will require submeteringSubmetering is used to determine the proportion of energy use within a building attributable to specific end uses or subsystems (e.g., the heating subsystem of an HVAC system). or deductive indirect metering of at least the main energy end-uses e.g. lighting, plug, major mechanical equipment, etc. The extent of the submetering is left to the discretion of the practioner, but it must be sufficient to demonstrate, through the M&V process, that the building and its systems are performing as projected.

thanks a lot!!!

I'm not sure if I am completely following your question, but I think that the problem starts with your interpretation of the 75% threshold. It refers to the area of a any single tenant, and determines whether that tenant falls into the category of Case 1 or Case 2 for the purposes of CI EAc3. It does not refer to the total tenancy of the building. My response to a related thread may help: http://www.leeduser.com/credit/CS-2009/EAc5.2#comment-9202.

5.2 is satisfied by submeteringSubmetering is used to determine the proportion of energy use within a building attributable to specific end uses or subsystems (e.g., the heating subsystem of an HVAC system). each tenant space independently.

For 5.1, you really need to start with your M&V plan. First decide which IPMVPThe International Performance Measurement and Verification Protocol (IPMVP) provides best-practice protocol for measurement and verification of new construction. This standard is referenced in LEED's measurement and verification credits. path you are following. The answer to questions 1&2 above depend on the M&V plan you develop. If the fans are AHU1.Air-handling units (AHUs) are mechanical indirect heating, ventilating, or air-conditioning systems in which the air is treated or handled by equipment located outside the rooms served, usually at a central location, and conveyed to and from the rooms by a fan and a system of distributing ducts. (NEEB, 1997 edition) 2.A type of heating and/or cooling distribution equipment that channels warm or cool air to different parts of a building. This process of channeling the conditioned air often involves drawing air over heating or cooling coils and forcing it from a central location through ducts or air-handling units. Air-handling units are hidden in the walls or ceilings, where they use steam or hot water to heat, or chilled water to cool the air inside the ductwork. fans, one per tenant, then typically they would be metered individually. I would probably not meter each pump, but would instead trend data from the pump VFDs through the BAS.

For question 3, it is certainly appropriate to calculate some end uses, rather than metering them directly. If you've metered the total, and everything but "x", you know "x" as well.

Actually, you could also gather data for each AHU1.Air-handling units (AHUs) are mechanical indirect heating, ventilating, or air-conditioning systems in which the air is treated or handled by equipment located outside the rooms served, usually at a central location, and conveyed to and from the rooms by a fan and a system of distributing ducts. (NEEB, 1997 edition) 2.A type of heating and/or cooling distribution equipment that channels warm or cool air to different parts of a building. This process of channeling the conditioned air often involves drawing air over heating or cooling coils and forcing it from a central location through ducts or air-handling units. Air-handling units are hidden in the walls or ceilings, where they use steam or hot water to heat, or chilled water to cool the air inside the ductwork. in the manner I described for the pumps. But for utility consumption accountability, you probably want AHUs serving a single tenant on the tenant electric meter.

Thanks Christopher!

I am using Option B: Energy Conservation Measure Isolation.

I understand from you that every AHU1.Air-handling units (AHUs) are mechanical indirect heating, ventilating, or air-conditioning systems in which the air is treated or handled by equipment located outside the rooms served, usually at a central location, and conveyed to and from the rooms by a fan and a system of distributing ducts. (NEEB, 1997 edition) 2.A type of heating and/or cooling distribution equipment that channels warm or cool air to different parts of a building. This process of channeling the conditioned air often involves drawing air over heating or cooling coils and forcing it from a central location through ducts or air-handling units. Air-handling units are hidden in the walls or ceilings, where they use steam or hot water to heat, or chilled water to cool the air inside the ductwork. Fan is to be metered alone.

Regarding the pumps, if I want to install submeters (and not trend data through the BAS), should I install for each of the primary and secondary pumps?

Many thanks!

If this is new construction and/or the ECMS implemented are interactive, Option B may not be appropriate. Under Option B, you need to meter the ECMs you have implemented.

To your specific question, I'm struggling to understand what you'd learn by metering the pumps individually.

Again, first develop the M&V plan. Design the metering per the plan.

In general, the M&V program is limited to the base building systems. If the extent of the base building is extremely limited, then the project may fall into the category of "not all projects are eligible for all LEED credits". I suggest a CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide in this particular case.

We were just discussing this very question under the LEED-EBOM EAc1 forum. I will refer you to that conversation.

The start point for the M&V effort should be outlined in your M&V plan. In most cases, the clock would start running at move-in, but in the case of phased occupancy as you describe, I think it is really up to the M&V folks on your team to identify the appropriate timing.

I agree with Chris on this, but would add that the building should be as close to full and stable long term occupancy as possible. The objective of M&V is to verify that the building is operating/performing as intended, and this can really only be accomplished if the building is occupied as intended.

Great question! I think this is pretty cool initiative. Unfortunately USGBC doesn't have any more info on it right now. LEEDuser is watching it closely and we'll post info on it when we can.

Any update on the Extra Point for signing the USGBC data release form? Getting ready to submit plans for 5.1 and 5.2. Thanks!

Jennifer, I'm glad you mentioned this.

USGBC has just recently been building out its Building Performance Partnership, which includes this. You can learn more about on this page.

I haven't yet talked to anyone who has tried to earn this point, so please post back here with what you learn in the process.

Dear all,

I am developing an M&V plan for a large commercial mall (1 for EAc5.1 and 1 for EAc5.2).

The initial electrical/power design groups the hot water primary pumps and the boilers together under one MCC (Motor Control Center).

Since the IPMVPThe International Performance Measurement and Verification Protocol (IPMVP) provides best-practice protocol for measurement and verification of new construction. This standard is referenced in LEED's measurement and verification credits. standard is flexible in terms of the number of meters/submeters and the entities being measured, do you think that I have to meter the boilers and the hot water pumps separately, or I can meter the "total heating" consumption by installing a meter on the MCC level (measuring boiler consumption + hot water pumps)? Or do I have the choice between both options?

Similarly for other MCCs which group "Cooling Tower Condenser pumps" with the "Chiller water primary pumps".. Can these be measured together under "Total Cooling"?

Thanks!

I would like to take this opportunity to point out a common mistake in the LEED submissions for this credit. The M&V Plan for 5.1 is not the same as 5.2, they are very different so don't submit the same plan for both.

Regarding your metering issue - you can meter these items together. When calibrating the model does it breakout these pumps or lump them together under and overall energy end use "pumps"? If lumped together calibrate to the total. If separate end uses in the model you could try and separate the two types of pumps using perhaps some spot measurements or run time information from the BMS to derive the energy use of the different pumps. The whole question is what information do you need to calibrate your model and what is the cheapest way to get that information?

The modeling program lumps all pumps together.

However, for the first scenario (Boilers + Hot water pumps), I think these should be separated, because the modeling program separates boilers (reported under "Heating") from Hot water pumps (reported under "Pumps").

Thanks Marcus!

But if the pumps are lumped together then you could calibrate the electric use of the pumps to the combined pump sub-meter.

The boiler heating energy use should be a gas sub-meter (assuming that is the fuel source). I am also assuming that there is more than one gas end use (hot water, cooking, etc.). If the boiler is the only gas use then the utility meter would work.