Hi all,
We are working on a campus project that includes two separate buildings and a mastersite. Both buildings would be served by boilers and chillers that are located in the basement of one of those buildings.
How do we go about modeling the HVAC side of this project? Do we need to go with District heating and cooling networks? If so, are there any specific guidelines we need to be following or are we allowed to go with ASHRAE 90.1-2007 App. G?
Any thoughts would be much appreciated.
Thank you.
Kind regards,
Nikos
David Eldridge
Energy Efficiency NinjaGrumman/Butkus Associates
68 thumbs up
September 30, 2020 - 2:46 am
What sizes are the two buildings, and just to clarify that one of the two buildings will have the plant equipment inside of it, and will that building be the larger building? Are the buildings being constructed at the same time?
There is some guidance included in the rating system that you should review before you get to Appendix G.
Arwid Theuer-Kock
1plus Consult GmbHSeptember 30, 2020 - 4:50 am
Hey Nikos,
refer to following guidelines:
https://www.usgbc.org/resources/des-district-energy-systems-guidance-v22-and-v2009-guidance-v20
and the interpretations under this search link, also for european situations
https://www.usgbc.org/search?Search+Library=%22DES+guidance+treatment+of+district+or+campus+thermal+energy+in+Leed%5C%22%22
greetings Arwid
Nikos Tsitsikas
2 thumbs up
September 30, 2020 - 8:39 am
Hi David,
Thanks for your message.
That is correct - the equipment (boilers and chillers) will be located inside the larger of the two buildings and will be serving both buildings. The larger building is about 14,000 m2 GFA and the smaller one 9,000 m2 GFA.
Yes, the buildings are being constructed at the same time.
What are you suggestions?
Thanks.
Kind regards,
Nikos
David Eldridge
Energy Efficiency NinjaGrumman/Butkus Associates
68 thumbs up
September 30, 2020 - 5:12 pm
That's helpful Nikos - I think the larger building with the plant inside of it will be treated with the equipment as part of the same building.
Then the second building would use district energy as the source fed from the first building using the district energy rules.
David Eldridge
Energy Efficiency NinjaGrumman/Butkus Associates
68 thumbs up
September 30, 2020 - 5:23 pm
One more clarification - although you could still use district energy approach being in the same building, the motivation would be if there were other third, fourth, etc. buidlings taking service from the plant so that some of the EA credits might not apply or if there were plant limitations that may be unfavorable.
In the case where everything is new your most straightforward path is to model and commission everything as a whole in B1, and only B2 would be subject to the DES calculations.
Nikos Tsitsikas
2 thumbs up
October 1, 2020 - 2:45 am
Hi David and Arwid,
Many thanks for your messages - these are very helpful indeed.
One more question - do those guidelines apply to v4 projects as well? I can see only v2.2 and v2009 being mentioned.
Thanks again.
Kind regards,
Nikos
Arwid Theuer-Kock
1plus Consult GmbHOctober 1, 2020 - 4:00 am
Hi Nikos,
I don´t know if they apply to v4. You mentioned that you have a v3 project or I guessed because you use ASHRAE 90.1-2007. you can investigate on the USGBC webpage or ask directly. They are very helpful.
Other issue: If you don´t have CHP you will not profit very much from the DES guidance described in the guide. I would recommend to proceed as follows:
a1) as you can´t consider the energy plant on master site level it has to be regarded in the corresponding building (technic, efficiency, commisioning,price of heat and cold...) as a normal plant but which is overimensioned for the individual building. You will mostly run, especally the chillers, in more efficient patial-load. I guess it would be appropriate to simulate the second building (building B) first to determine the heat and cold load profile and then Building A with the additioal heating and cooling loads of Building B to reflect the efficiencies correctly if your simulation tool is capable of this .
a2) for the second building B you can consider supply heat and cold from building A (or a virtual plant) with efficincy losses because of heat exchangers, if exists at all. Otherwise set efficiency of energy supply to 100%. energy prices are the same.
b1) perhaps your software and the project process allows to simuate the two buildings at once and evaluation seperate (perhaps with postprocessing). Then you prove performance of the main plant in the realistic situation
in both cases the baseline buildings are modelled and simulated seperately with the appropriate plant and efficiencies due to ASHRAE.
Ad a narrative in special circumstances in both campus projects or an additional document to explain the situation.
Which approach you even chosse, I recomend to clear and discuss it with USGBC/GBCI support in front of beginning.
Which software do you use?
regards arwid
Nikos Tsitsikas
2 thumbs up
October 1, 2020 - 9:04 am
Hi Arwid,
Thanks for the reply.
Yes, this is a v2009 project; however, we will be facing a similar situation on a v4 project in the near future, that's why I was wondering if the same principles would apply.
We are using IES VE for energy modeling - are there any specific tips you would like to share with us on how we could run this process on IES VE?
Also, we do not have CHP; hence, what you are suggesting is to build and run the models for the two buildings as usual - using the ASHRAE 90.1 guidelines - and then provide a clarification document which would explain our approach and strategy?
Am I correct?
Thank you.
Kind regards,
Nikos
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5912 thumbs up
October 5, 2020 - 2:16 pm
The v4 district guidance is incorporated into the LEED Reference Guide and there are some significant changes.