1. what is the difference between Bldg. Average equipment power density method and Space by space equipment power density method?
2. If we select Space by space equipment power density, the form is asking Building Type, but the selection has an options of different space type. Can we use them instead of selecting Fire Station as one type?
3. Total space type (sq ft) - is this referring to the sq ft of each space type eg. station office or dining area (sq ft)?
4. what do you mean by Equipment Power Density (W/ sq ft)?
5. What do you mean by "Equipment Included in Power Density" ?
Appreciate your assistance on this.
Regards,
Susan
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
July 30, 2018 - 3:57 pm
1. The average would be adding up all of the equipment loads in the building and then dividing by the building area, then you use the result for the equipment load in each zone in the model. The space-by-space would be where you enter the load in that space within that space. The later is highly recommended relative to accuracy, especially in buildings where this load varies by space type.
2. If you use the average you could just select the overall building type. If you use space-by-space then you would indicate the space type.
3. Yes
4. Let's suppose you have a computer/monitor that is 100 watts in a room that is 200 square feet. So the equipment power density is 0.5 Watts/square foot. To determine the W/sf in each space you need to know the space or building type and use a referenced value (I think these are somewhere within Title 24 and can also be found in the 90.1-2010 Users Manual and COMChek) or you add up the actual loads planned for each space and calculate it yourself. Again the latter is more accurate.
5. Equipment included in the equipment power density would refer to the type of equipment in that space. So in an office it would be office equipment. In the lunch room it might include a refrigerator, stove, coffee maker, dishwasher, etc. In a lab space it would be the lab equipment. In a warehouse it could be rechargeable forklifts, etc, etc.
susan eguia
LEED Coordinator/Construction Administrator/Business DevelopmentBuilding Solutions Group, Inc.
59 thumbs up
July 30, 2018 - 6:13 pm
HI,
thanks for quick response.
# 3 - Square foot in each space type (eg. office) is it the same from T-24 Square feet conditioned area? The i will include which equipment included in power density?
#6 - the red flags says"the receptacle equipment consumption for the baseline and/or proposed is greater than 40% (less than 10%) of the total building site energy usage which is unexpectedly high (low). This check was made using the Performance rating energy consumption and cost by fuel type table. Verify that the receptacle equipment has been modeled as accurately.
Is the error referring to "Total Power for receptacle equipment" which is 46.6 ? If so, we already input the average Watts (7.27) for each space type via "space by space method". Likewise, we also use "Building Average method" but the results are the same -- still 40% higher.
Can we just leave it the red flags like that and provide explanation?
thanks,
Susan
susan eguia
LEED Coordinator/Construction Administrator/Business DevelopmentBuilding Solutions Group, Inc.
59 thumbs up
August 2, 2018 - 10:18 am
Hi Marcus,
Just want to clarify:
1. For Receptacle Equipment Modeling Method under "Building Average equipment power density" which Square Foot should we use - Conditioned Area from T-24 or the total building area Square Foot reported from Project Information?
2. If we use "Space by space equipment power density" method should we use the average Watts or the assigned Watts for each space.
3. We input the average for both method but we still have the same results - 40% higher (less than 10%) of the total building site energy use. - can we just leave it like that and provide additional info?
Appreciate any input on this.
thanks,
susan
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
August 3, 2018 - 1:14 pm
#3. Probably I am not as familiar with T24 as I am with ASHRAE 90.1.
#6. The flag is referring to the energy use for receptacle equipment, not the power. In an office building the typical energy consumption for receptacle equipment is about 25%. Yes you are supposed to provide a response to all the items highlighted.
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
August 3, 2018 - 1:16 pm
1. The total I think.
2. Assigned.
3. Sure.