In addition, quoting 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. Vol III, Concepts and Practices for Determining Energy Savings in New Construction, Part I, page 18:

"Option D Involves of computer simulation of whole building energy use. The Post-Construction Energy Use is determined by utility metering and/OR 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 by using an energy simulation model of the as-built building calibrated to metered energy use data."

GH

I think I was the one who also asked Marcus regarding this issue. I think the reviewer will look for the method of how we can reach the end-use energy data. Some of them might require only runtime record if the equipment consume constant power. I used to create 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. plan this way and try to find the solution for obtain the data for each end-use (fan, chiller, pump, light, etc.). Yes, the 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). is not mandatory if you can find to solution to extract the end-use from the whole.

Good to see someone reading 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.! I am not sure too many folks submitting M&V Plans have done so.

Let me see if I can explain the the rationale for needing energy end use data. First of all I do not believe I ever said that projects had to install submeters. There are several ways to get energy end use data and 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). is just one of them. Sometimes it is not even actual energy use data as it could be data you would use to calculate energy use. You are correct that submeters or any direct measurements of energy use by end use are not required.

You will still need to calibrate your energy model by energy end use and have a data gathering plan in place to enable it. If you just calibrated to the monthly utility data by fuel type you could very easily be over predicting one end use and under predicting another and on balance the result may "appear" to match but it doesn't. You will find that it is virtually impossible to get each month to match within a reasonable range. When it does not match then you will need to have some kind of energy end use data to figure out the discrepancy. So the M&V Plan must include a methodology to gather the data needed by energy end use. It cannot be an afterthought that you will figure out after the results do not match. I can guarantee that the monthly data will not match in all cases so you are going to need some additional data. I think anyone who has calibrated an energy model would attest to this fact.

Recently we gathered some whole building data for a project we modeled that was an all electric building. Our model was within 6 kWhA kilowatt-hour is a unit of work or energy, measured as 1 kilowatt (1,000 watts) of power expended for 1 hour. One kWh is equivalent to 3,412 Btu. in the annual total energy consumption. Pretty good huh? Well it turns out we over predicted heating and under predicted cooling and on balance we got lucky. Even if each month was within range we would not have a calibrated model.

Unfortunately the language in the IPMVP is often a bit vague. It sets out broad goals and lets you figure out how to get there. Based on first hand experience I can tell you that you can't calibrate to the utility bills without calibrating to energy end use. Another way to think about it is to focus on the outcome. The energy model basically needs to be fully reflective of the way the actual building operates in order to be accurately calibrated. Without any energy end use data I would suggest that it would be impossible to do so.

Now the question becomes do we need to measure or meter each energy end use? Probably not. Very small ones that do not have a big impact on the overall energy use can be estimated. Maybe HVAC can be lumped together instead of trying to break out fans, pumps, heating and cooling. Some end uses could be derived from subtraction. This starts to get very project specific and how you do it depends on many factors.

If you can make the case in your M&V Plan that you can accurately calibrate the energy model without any energy end use data I would like to read how you will do it. If you think it through you will find that it is not possible unless you have clairvoyant energy modelers!

Marcus, thanks for your comment. I think it was very clarifying.
Then, the key point is how to calibrate the model by energy end use. We have some ideas:

1.Sub-metering
2.Utility bills (in big projects utility bills could be differentiated by end use)
3.Data loggers that record energy use in different circuits according to the modeler's needs. Data could be recorded over a 7-day period (for example) and estimate the rest of the month.

Is this correct?
Someone could bring up more options?

Yes you are correct. Here are some others.

You can take spot measurements and use that data to calculate the energy use. For example, if I know that the lighting is a constant load (i.e. always on) and the schedule is consistent (on at the same time, off at the same time) I could use a clamp on meter, measure the wattage of each fixture type, count the fixtures and do the math.

I mentioned subtraction before. For example, if you meter lighting, hot water and HVAC you could derive plug loads by subtracting the submetered data from the utility meter data.

Some information can be obtained through interviews with operational staff. Things like occupancy and schedules are often obtained this way.

Commissioning activities often yield useful information what can be used in calibration.

Hand calculations could be used to verify very small constant loads if necessary.

And do not forget to calibrate the weather file to reflect the actual weather during the M&V period.

Absolutely helpful. Thanks again and I hope this helped other project teams to earn this credit.

GH

You basically take the calibrated model of the building and use that to create another Appendix G baseline model. This is your calibrated baseline for comparison.

So the adjusted schedules, utility rates, occupancy, etc. that must be identical are taken from the calibrated model and applied to the Appendix G baseline model.

Thank you for your soon feedback. What you indicate is what I understood but the Reference Guide says "Calibration is achieved by adjusting the energy simulation model to reflect actual operating conditions and parameters. Next, the conservations measures are removed from the model to define the baseline..." so, this sentence is kind of confusing because it seems that, for instance, if one of the conservation measures was to insulate the walls, then in the EAc5 baseline models the walls should appear without insulation (removing the conservation measures). Id appreciate if you can clarify further.

They mean that you should take the level of wall insulation from what you have in your building back down to the code minimum insulation value. An Appendix G baseline does just that.

Thank you Marcus

We have explored the possibility of doing so on a couple residential projects. The complexity involved in gathering the necessary data is far higher with these types of projects and as a result each time we explored it it was abandoned as too difficult and expensive.

If you do pursue it I would suggest that perhaps you consider a sampling protocol for the units to keep the cost down.

Thanks, Marcus. I should clarify - the owner is willing to bear the cost. How do we get the information from the service provider if the tenant isn't responsible?

Thank you.

Getting the electric bills for some or all of the tenant spaces could be helpful but this is just a small part of the information you will need. Having the units sub-metered for electricity would be a good check against energy end use data you will need to gather from at least a sampling of units. If the units are sub-metered and the utility does not read them then you may need to read them yourself. Who owns the sub-meters?

As I said these projects are very difficult to properly implement M&V. In order to do this correctly you need to gather energy usage data for each energy end use, not just by fuel type. So lighting, heating, cooling, fans, plug loads, etc. This data can be gathered through building sub-meters installed by the owner or through a combination of short term trend meters and spot measurements. Sub-metering costs upfront but saves on labor during implementation. Gathering the data by hand (trend meters/spot measurements) is cheaper upfront but prohibitively expensive in all but relatively small buildings.

Just so your owner is aware, the metering and implementation cost to do this right for even a medium-size residential project could easily be $50,000 to $100,000. This is why most projects take the easy Option 3 point and run away from the M&V Plan. How many units and what is the square footage of your project?

I think that sampling could work for a project like that. Off the top of my head something like at least 10% of the units would need to be included. In addition to the overal electric usage you would need to figure out how to determine energy use by end use (lighting, HVAC, plug loads, etc.) within each of the sampled units. How you do that would need to be part of the Plan.

Typical tolerances are +-10% on a monthly basis for each energy end use.
Corrective actions are triggered if the savings are not within the tolerance following the calibration.

You would also need to extrapolate the results of the sample to the whole building and the entire building calibration would need to be within the established tolerance.

Unfortunately apartment building are much more difficult to do correctly than many other building types so this credit is not often pursued for this project type.

It depends on the individuals involved. It is very hard to make such generalizations but in general the CxAThe commissioning authority (CxA) is the individual designated to organize, lead, and review the completion of commissioning process activities. The CxA facilitates communication among the owner, designer, and contractor to ensure that complex systems are installed and function in accordance with the owner's project requirements. is probably in a better position to do this work since they are already going be doing some of the work required. Be careful however that whoever does it must have a thorough and complete understanding of what needs to be done. M&V is not just some enhancement to the Cx1. Commissioning (Cx) is the process of verifying and documenting that a building and all of its systems and assemblies are planned, designed, installed, tested, operated, and maintained to meet the owner's project requirements. 2. The process of checking the performance of a building against the owner's goals during design, construction, and occupancy. At a minimum, mechanical and electrical equipment are tested, although much more extensive testing may also be included. process and requires a somewhat different focus.

Who is doing the project's energy model? Typically whomever does the initial modeling would need to be involved in the M&V effort.

You earn one point for EAc5 if you agree to provide your data under MPR 6.

So it is basically a free point by just complying with the MPRs

Also, how far back can this point be claimed? I am working on a project that is under the NC-2009 rating system and is currently under review, but project was registered a couple years ago and at the time we indicated that we would be attempting 3 points for EAc5. However it looks like we will be at 59 points (1 point short of our desired Gold). We have been in the process of trying to get together the M+V Plan but with a significant cost. It would be great if we can stop our efforts and get the additional point under EAc5 Option 3.

Any help you can provide is appreciated.

Basically.

You could change your mind and pursue this option in the middle of your review.

Make sure you have both a monthly and annual target for each energy end use. It is not sufficient to have only an annual total accuracy target. Typically the targets are expressed as +-XX%. The target can vary but is usually in the 5% to 20% range depending on the situation and the project. +-10% is a very commonly used value in alignment with Guideline 14.

There was a post by Gord Shymko in one of these EAc5 credit forums with more detail on this issue. Might want to search the other versions of LEED under this credit.

Genko, please see Option 3 in the EAc5 credit language, above.

You will need to calibrate the model by energy end use on a monthly (and annual) basis.
1. if you trend this data you could figure out energy use
2. how will you determine energy demand? It will need to be measured.
3. subtraction from metered data is a viable method
Yes you would need to separate out the electric end uses in order to calibrate the model. Whole building metered data is not sufficient.

For the process load, I can know the energy demand for computers, printer, elevator, dishwasher etc. The computer energy consuption can be calculated with occupancy time, and the other energy consumption with operating time. But this method is not exact. Will this solution be accepted?

But how do you know the actual energy demand for those items? Rated and actual are often very different. You will need to measure actual consumption. This can be through direct sub-metering, spot measurements, short-term trends, derived from other measured data, etc. This cannot be based on the same method used to make the prediction. You need to measure something in the actual operation of the building to confirm the consumption you predicted. If it is not the same then you make adjustments (calibrate) to the model until the values match within your tolerance range.

Under Option D you are attempting to make adjustments to your model so that it matches the utility bills (monthly and annually by end use). So what information do you need in order to do that? Totals are not enough because even if you match exactly you could just be lucky. We did an energy model a couple of years ago that was within 6 kWhA kilowatt-hour is a unit of work or energy, measured as 1 kilowatt (1,000 watts) of power expended for 1 hour. One kWh is equivalent to 3,412 Btu. based on the first year of actual operation. When we looked at the monthly data we under-predicted heating and over predicted cooling and on an annual basis we just got lucky. But as you can see just because some numbers match does not mean we had a calibrated model. The whole point of Option D is to create that calibrated model which is then used to verify savings relative to a calibrated baseline.

If you understand what you are trying to do the question of what to meter and how to do it usually falls into place.

Very hard to say from the limited information provided. 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. does not require you to measure every energy use. Can the use be derived by other means, say subtraction? Is the use virtually inconsequential (less than 1% of total consumption)?

Sounds like exterior lighting powered by a battery which is charged by photovoltaics and the system is controlled by a photocell? If so as a renewable energy source it should be measured. This does not means it needs to be metered. Can the usage be derived by other means?

Under Option D you need to calibrate the entire energy model. You are not evaluating ECMs in isolation, that is Option B. However this option rarely applies to new construction since it is not appropriate for projects with interactive ECMs. So you need to either measure or be able to derive every major energy end use.

What if we mornitor the enitre cooling system, so it will include cooling tower and chiller and pump under one sub-meter. is this considered 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). of "major" system of the HVAC? we are not plan to measure pump, chiller, and cooling tower saperately.

Does the electric domestic hotwater consider as a major energy components to be submeterSubmetering is used to determine the proportion of energy or water use within a building attributable to specific end uses such as tenant spaces, or subsystems such as the heating component of an HVAC system.?

thanks

I am not going to be able to tell you what you should submeterSubmetering is used to determine the proportion of energy or water use within a building attributable to specific end uses such as tenant spaces, or subsystems such as the heating component of an HVAC system. as I am not familiar with the project. You will need to answer this question for yourself relative to each end use - does this measurement give me the data I need to calibrate my energy model? Whether you submeter or not is generally a question of the efficiency of implementing the plan. 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). generally reduces the time you have to spend in the building gathering data by hand so it is often more efficient to gather data this way but that must be weighed against the cost of the submetering.

In general what you propose would potentially get you the cooling and some or all of the pump energy. Some modeling software separates the cooling tower end use from the chiller so you may need to somehow gets an idea of the relative energy use of each. Figure a way to break out the pumps from the total and those end uses might be covered. For example, if the pumps are variable speed then the controlled can often be programmed to gather the pump data needed to determine energy use.

Domestic hot water in a hotel is generally a major energy user. Anything over say 5% of the total energy use would be major in my opinion.

Thanks so much.

You need data gathered by each energy end use, so yes you must cover all of it. How you get the data depends on what is the most cost-effective means to gather it. So sub-metering is not specifically required. You can gather this data with spot measurements, short term trending meters, or even derive it by subtraction (i.e. you measure all electrical use except plug loads so you can derive plug loads by subtracting from the whole building electric meter).

Your focus in Option D is to gather the data you need to calibrate the energy model. So your plan should detail how you are going to gather the data. The data may not even be direct energy use. For example, a measurement of run time on a constant volume fan will allow you to derive energy use.

The level of monitoring varies depending on the project. Some projects may be small enough to lump all HVAC together and still enable a reasonable M&V approach. Some larger projects would probably require data gathering from system components.

M&V is pretty simple - gather the data you need to calibrate your energy model; calibrate your energy model to the utility bills (monthly and annually); create a revised baseline model from your calibrated model; the difference is your verified savings. Basically measure - verify.

Thanks so much Marcus.

What if my project is a hotel with many guest rooms. I have submeterSubmetering is used to determine the proportion of energy or water use within a building attributable to specific end uses such as tenant spaces, or subsystems such as the heating component of an HVAC system. for each room but it measure all the energy use in a room not the enduse. Any suggestion for this case.

Jatuwat

You could use the sub-metered room data to verify spot or short-term trend measurements in a sampling of rooms. Assume you are sub-metering electric only right? For all the plug in devices you could use Kill-a-watt meters. For the hard wired you could use clamp on meters for spot measurements or trending meters like the ones from Hobo to gather the data you need. Add it up and use the whole room meter to verify your measurements. So you could gather data in say 10% of the rooms, apply occupancy data for the rooms and extrapolate for the whole building.

If the building you are submitting meters the incoming DES energy use then you should be able to use the reporting option.

I think it would be eligible there too.

Option B however is severely limited in new construction/major renovation projects since it is not applicable to projects with a series of interactive energy efficiency strategies. Often it is not possible to isolate and evaluate each one as required under Option B in LEED projects and it is very rarely applied.

Option C is explicitly prohibited for LEED and Option B is usually only allowed in very limited circumstances. The Baseline should be the same as was submitted for EAp2/EAc1.

It sounds like you have not yet submitted your M&V Plan to LEED but the LEED submission is not final? If you are still in the review process you can revise the M&V Plan, follow Option D and still get the points.

If you will have the data needed to calibrate the model with the actual utility bills then just create a calibrated baseline and determine the savings.

Thank you very much Marcus. We are having a separate consultant do the LEED compliant M&V plan.

Ameet,
You are correct. LEED NC is a Design and Construction tool. It does not require you to submit follow up information Post Occupancy. This is true other similar credits which require follow up by the project team but no additional documentation: IEQc7.2, EAc3, etc.
The Living Building Challenge is a rating system that is based on actual performance rather than only design.

Dylan is correct, but I would note that the Living Building Challenge is comparable as another design and construction system that follows up after occupancy.

LEED-EBOM is another LEED rating system that addresses actual building performance.

Based on 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. there are no requirements for any permanent metering. I cannot address the list above as I did not write it, however, your M&V Plan must include a thorough description of the data acquisition strategies for getting the data you will need to calibrate your model. If your metering is set up to directly measure or derive all of the energy end uses from your model this part of your M&V Plan should be covered.

Yes and no. The same model used for EAc1 should be used for EAc5. The difference is that the EAc5 baseline has been created from the Proposed model which has been calibrated to reflect the actual final construction, operating schedules, weather, etc.

You can develop a M&V Plan anytime prior to your construction submission for LEED. The controls relate only as your control system is set up to provide at least some of the data you will need to perform the M&V. At this point you are basically stuck with the currently installed data collection which was installed (unless you want to spend more money) so depending on the set up you may have to gather data the old-fashioned way through spot measurements and short-term trending meters.

Even though Portfolio Manager does not cover your building type you can still enter the data for USGBC through it. Alternatively you can send the data to USGBC. Contact LEEDPerformance@usgbc.org for specific instructions.

You might be able to use the local standard but it would imply some risk in LEED.

The purpose of this credit is to verify the energy savings you predicted under EAc1 Optimize Energy Performance. Using something other than the model you have submitted for EAc1 will require much explaining and justification. You may or may not be able to do so, but trying to use the local standard is risky for LEED.

Just like you had to do a model under 90.1-2007, the M&V Plan should be based on it too. Sounds like you have to use NS3031:2007 in operations anyway.

Thanks Marcus.
I guess we have to discuss this with the building owner. There will be some more work to be done, and a little bit higher cost for operations on the maintenance staff.

Hey Rob,

The metering needs to get to individual energy end uses (i.e. lighting, plug loads, HVAC, etc.) and does not have to be permenent. You might consider doing some spot measurements and short-term trending on a sampling of units as a possibility if you can get enough owners to cooperate. Having a whole unit meter on those would be a good idea too (assuming that the units are not separately metered already).

You don't have to measure everything but need to derive everything based on your measurements.

The purpose of this is to validate energy savings.

DDC points and the information needed to perform the verification are very different things in many cases.