District thermal energy

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Hi friends,

I am working on a project which comes under "Required Treatment of District
Thermal Energy in LEED-NC version 2.2 and LEED for Schools", Version 1.0,
May 28, 2008 document.

My project is a hotel building (80% residential and 20% non-residential).
Hence as per my understanding the system type will be system 2 (residential,
as per table G3.1.1A and G3.1.1B).

I received a review comment which says that

Per ASHRAE 90.1-2004, tables G3.1.1A and G3.1.1B, the baseline system for
this project shall be System #2 ? Packaged terminal heat pump. Also, since
the project includes more than 20,000 square feet of non-residential space
in addition to the large residential occupancy, all residential spaces
should be modeled in the Baseline as System Type # 4 (if the total
conditioned building area is less than 150,000 square feet) or System Type #
8 (if the total conditioned building area exceeds 150,000 square feet).
Please include the requested information on the Template and revise the
Tables 1.4, 1.8.1, 1.8.2 and the model as appropriate.

My questions are:

1. The project will come under residential category or non-residential
category or both?? My system selection is correct??
2. Do anyone has the backup or support which confirms the line "since
the project includes more than 20,000 square feet of non-residential space
in addition to the large residential occupancy,"?

Thanks in advance.

Neeraj Arora

neeraj arora's picture
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Neeraja,

Here are some answers;

Question 1: The third footnote below table G3.1.1A says to use the
predominant condition when more than 1 system can be applied.

Question 2: ASHRAE 90.1-2004 Exception G3.1.1a is the source of the 20,000
sf comment.

Brett Fero's picture
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Joined: 2011-09-30
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Hi Brett,

Thanks for such a prompt response.

In my case total conditioned space is 2,69,920 sqft as per eQuest output
report LS-C command.

Out of which almost 36,000 sqft is non-residential space (corridors,
administrative offices, mechanical electrical spaces-all conditioned) and
rest (2,33,920 sqft) is residential space (guest rooms, dinning space,
prayer rooms etc).

Hence residential space is predominant.

This means I need to select:

Case1: system-4 PSZ-HP for non-residential space and system-2 PTHP for
residential space.

OR

Case2: System-4 for all spaces (residential and non-residential spaces)

OR

Case3: System-8 as the residential space is > 150000 sqft

OR

Case4: System-2 for all spaces, because residential space is predominant

Kindly suggest.

Thanks & Regards,

Neeraj Arora

neeraj arora's picture
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Joined: 2011-09-30
Reputation: 0

Neeraja,

Here are some answers;

Question 1: The third footnote below table G3.1.1A says to use the
predominant condition when more than 1 system can be applied.

Question 2: ASHRAE 90.1-2004 Exception G3.1.1a is the source of the 20,000
sf comment.

Brett Fero's picture
Offline
Joined: 2011-09-30
Reputation: 0

Hi Brett,

Thanks for such a prompt response.

In my case total conditioned space is 2,69,920 sqft as per eQuest output
report LS-C command.

Out of which almost 36,000 sqft is non-residential space (corridors,
administrative offices, mechanical electrical spaces-all conditioned) and
rest (2,33,920 sqft) is residential space (guest rooms, dinning space,
prayer rooms etc).

Hence residential space is predominant.

This means I need to select:

Case1: system-4 PSZ-HP for non-residential space and system-2 PTHP for
residential space.

OR

Case2: System-4 for all spaces (residential and non-residential spaces)

OR

Case3: System-8 as the residential space is > 150000 sqft

OR

Case4: System-2 for all spaces, because residential space is predominant

Kindly suggest.

Thanks & Regards,

Neeraj Arora

neeraj arora's picture
Offline
Joined: 2011-09-30
Reputation: 0