Mass Stretch Code: TEDI calcs

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Hi group,

Hope everyone is doing well. We are working on a school building in MA and need to perform "TEDI" models. I've read through the documentation and am a little confused if it's a load metric or an energy metric. The limits are expressed in kBtu/sf/year in the code language, but some of the supporting documentation about how to extract this from equest/IES/ energy plus makes me feel like it's a load metric. It has to be one the three and it seems like its option B

1. Peak Heating and Cooling load per SF
2. Sum of annual heating and cooling loads (annual) per SF - without efficiency accounting
3. Sum of annual heating and cooling energy per SF - with efficiency accounting

https://www.mass.gov/doc/updated-guidelines-for-tedi-and-ashrae-app-g-modeling/download

Appreciate your responses!

Thank you

Madhav

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MADHAV MUNSHI BEMP
Senior Associate
mmunshi at kohlerronan.com

KOHLER RONAN | Consulting Engineers
171 Madison Avenue, New York, NY 10016
212.695.2422

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Hi Madhav,

TEDI is a metric for the building envelope and ventilation load performance.
You can sum heating (ONLY) coil loads to determine the output. This is a
clip from the guideline we use in Canada (BC) that explains it. M.F.Area is
building area excluding unconditioned indoor parking area, but including all
other partially and unconditioned areas. So yes, the answer is option B,
excluding the cooling. It is not the peak (A) and does not include heating
system efficiency (C).

Shaun

Shaun Martin, BEMP, LEED-BD&C

Principal

Shaun Martin Consulting


smartin at shaunmartinconsulting.com

+1-604-789-1095

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Niknam Khosravani Fard LEED AP
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Option B is indeed the correct answer. The detailed energy modeling
guidelines for the MA Stretch Energy Code are about to be published. Till
they are out, I recommend checking out the version that was posted for the
public comments
.
Note that the modeling rules are quite different from Vancouver & Toronto
versions.

Thanks,

Maria

On Thu, Jul 27, 2023 at 7:07?PM Niknam via Bldg-sim <

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*Maria Karpman *LEED AP, BEMP, CEM

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Niknam Khosravani Fard LEED AP
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Thank you everyone for your responses. All of you confirmed that it is indeed Option B.

The MA 2023 Commercial Stretch code document (linked here) has a table on the TEDI limits
https://www.mass.gov/doc/225-cmr-2200-commercial-specialized-stretch-energy-code-redline-june-24-2022-0/download

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Based on this table, the TEDI for heating averages 2.5 kBtu/sf/year. From a site EUI perspective, it would mean that if this was a fossil fuel system the site EUI would be about 2.8 kBtu/sf/year and for an all-electric HP based system, the site EUI would be about 1.13 kBtu/sf/year or lower. And the models are expected to include envelope, infiltration, ventilation, and exhaust systems. It seems like envelope and infiltration loads are expected to be near 0. So, maybe its only ventilation and exhaust for heating loads.

But even then, aren?t these targets super aggressive? Is there any documentation that shows that this is possible to achieve in a real-world scenario?

MADHAV MUNSHI BEMP
Senior Associate
mmunshi at kohlerronan.com

KOHLER RONAN | Consulting Engineers
171 Madison Avenue, New York, NY 10016

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