See all forum discussions about NC-2009 EAp2
 Subscribe to new posts about NC-2009 EAp2 Post a new question aboutNC-2009 EAp2
See LEEDuser’s guidance on NC-2009 EAp2»
FAQs about EAp2 :

Our project has a large process load—75%. Despite our efforts to make an efficient HVAC design, the cost savings are minimal. What can we do to earn this prerequisite and be eligible for LEED certification? Is there any flexibility in how we model the p

Can SHGC be higher in the proposed than in the baseline model?

Our process load is higher than 25%. Do we have to justify that?

Do I need to justify the electrical and fuel rates I am using in my model?

Our local code references ASHRAE 90.1-2010. Should I use that for my documentation, or 90.1-2007?

Can I claim exterior lighting savings for canopy lighting even though a baseline model cannot include shading elements?

The project is built on a site with existing exterior lighting installed. How should this be accounted for?

Can mezzanines open to floors below be excluded from the energy model?

How do I provide a zip code for an international location?

For a project outside the U.S., how do I determine the climate zone?

For a project outside the U.S., how do I determine the Target Finder score?

Do hotel rooms need automatic light shut-off control?

How commonly are the 90.1 mandatory compliance forms submitted as part of EAp2/EAc1?

The Section 9 space-by-space method does not include residential space types. What should I use?

Can the Passive House Planning Package (PHPP) be used to energy model for LEED?

Is it acceptable to model a split-type AC with inverter technology compressor as a heat pump, like modeling VRF?

Can the Trace 700 'LEED Energy Performance Summary Report' by uploaded to LEED Online in lieu of the Section 1.4 tables spreadsheet?

A portion of our building envelope is historic. Can we exclude it from our model?

Which baseline HVAC system do I use if my building has no heating or air conditioning?

For an existing building, do I need to rotate the model?

View answers »

Forum discussion

NC-2009 EAp2:Minimum Energy Performance

Basement Ventilation exceptional calculations

Our project has 4 basements with fresh air, exhaust and circulation fans. The logic of exhaust fan functioning is designed such that during normal mode only few fans operate, during pollution mode few more fans additionally switches on. CO sensors are installed to monitor and control the fan operation. Can we take benefit for this logic in exceptional calculations as per the guidelines outlined in advanced energy modelling guide appendix (Like a dual speed fan)? If yes, the baseline has to be defined for 0.75 Cfm/sft and 0.3W/cfm as per ASHRAE. But these values are only for the exhaust fans in normal mode alone. (Please correct if the understanding is wrong). Then how to take benefit of the logic defined to save energy?. Also how to do the exceptional calculations for the fresh air and circulation fans running in dual speed mode? Thank you !

0
Post a reply

You rely on LEEDuser. Can we rely on you?

LEEDuser is supported by our premium members, not by advertisers.

Go premium for $15.95  »

Profile picture for user sheffer
Marcus Sheffer
LEED Fellow
7group / Energy Opportunities
LEEDuser Expert
4454 thumbs up

Thu, 11/20/2014 - 15:11

Sounds like these basements are parking garages? If not where is the CO coming from? If it is CO sensor control of ventilation (and this is not standard practice in the area of the project) then yes you can claim the savings. Per LEED Interpretation 10371, the project team must demonstrate that the proposed design goes beyond standard practice and this measure must be modeled as an Exceptional Calculation Measure (ECM). In order for approval, the following conditions must be met. Address each of the following: a. Baseline case shall meet the requirements of ASHRAE 90.1-2010, Section 6.4.3.4.5 Enclosed Parking Garage Ventilation. Baseline fan volume shall be based on the minimum required ASHRAE 62.1 parking ventilation rates of 0.75 cfm/square foot. Baseline system fan power shall be calculated at 0.3 watts per CFM. b. Proposed case shall reflect the actual design. Evidence shall be provided documenting that demand control ventilation strategies are sufficient to automatically detect contaminant levels of concern in parking garages (Carbon Monoxide, Particulates, VOCs, etc. and NO2) and modulate airflow such that contaminant levels are maintained below specified contaminant concentration as identified in ASHRAE 62.1-2010 Addendum d. Evidence shall also be provided that contaminant sensors are placed in space in an appropriate manner for detection of contaminant in question and that the sensors be calibrated yearly. c. If other activities occur in the garage area, the ventilation for these uses shall be in addition to garage vehicle ventilation. d. Proposed case shall be modeled such that a minimum air flow of 0.05 cfm/square foot is maintained. e. A narrative shall describe all Baseline and Proposed case assumptions included for this measure, and the calculation methodology used to determine the projected savings. The narrative and energy savings should be reported separately from the other efficiency measures in the LEED Form. f. No more than a 75% fan energy savings shall be claimed for this measure.
Default Avatar
Chilufya Lombe
Sustainability Consultant
Solid Green Consulting
LEEDuser Basic Member
23 thumbs up

Thu, 11/20/2014 - 15:22

Hi Marcus, this response answers a question I asked round about the same time. Please ignore my query when you get to it.

Fri, 11/21/2014 - 09:39

Hi Marcus, Thanks for the reply. Yes, the basement is used for parking only. Is the fan power of 0.3 W/cfm defined as per 62.1 is only for the exhaust fans or includes fresh air fans as well?
Profile picture for user sheffer
Marcus Sheffer
LEED Fellow
7group / Energy Opportunities
LEEDuser Expert
4454 thumbs up

Fri, 11/21/2014 - 14:47

That is the total baseline fan power - 0.3 W/cfm of maximum supply airflow.

Add new comment

To post a comment, you need to register for a LEEDuser Basic membership (free) or login to your existing profile.