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Questions/Issues with Parametric Analysis Tool (PAT )

asked 2015-07-14 19:58:44 -0600

updated 2017-08-20 15:05:06 -0600

I am using the PAT tool to evaluate some design alternatives, and finding some workflow questions/potential issues that I am hoping to get some help with:

  1. What is the rationale for not being able to combine Measures from the same Measure Group into one Design Alternative?

  2. On the Run Simulations screen, I can't select individual Design Alternatives and run them. Should I be able to do this?

  3. Creating a new Measure/Measure Group, or reordering of Measures, causes the Design Alternatives I created to be deleted. Is this a bug, or what is the rationale for this?

Using OS v1.7.0

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@DavidReddy I changed your bullets to numbers for referencing in the answers.

MatthewSteen's avatar MatthewSteen  ( 2015-07-14 21:18:28 -0600 )edit

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answered 2015-07-14 22:46:05 -0600

updated 2015-07-14 22:49:01 -0600

1) The intent is that a single measure with different values will constitute a single measure group. For example, the window-to-wall ratio measure could be used multiple times within a single measure group with WWR values of 0.2, 0.3, 0.4, and 0.5. You would only apply one of those variations in a single design alternative since they're mutually exclusive to each other - that is you wouldn't apply a WWR of 0.2 as well as a WWR 0.3 to your building. So when you go to the second tab, you can just click the "create one of each" button to quickly create a design alternative for each WWR. Hopefully that makes sense.

2) No. The expectation is that you're running all of the design alternatives that haven't yet been run when you poke the arrow button. The select feature is really best used when running with AWS when you want to download detailed results of specific alternatives from the cloud. You can also select alternatives to clear the results, which allows you to re-run specific alternatives.

3) Yeah, that's irritating right? The reason has to do with how PAT stores results internally within a database, and how the database is updated when alternatives are added. It's strictly a limitation of how PAT was coded. We know this is something people would like changed, and it should be addressed within the next year when we re-work PAT to integrate more of the capability built into OS Server. Stay tuned!

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Thanks very much for all the responses Larry. The rationale for 1) seems obvious from the perspective of applying measures to the whole building. However, it is not uncommon to break the building into smaller components, and have the same or similar measure for each component, allowing you to see the impact more iteratively.

DavidReddy's avatar DavidReddy  ( 2015-07-15 10:52:48 -0600 )edit

... For example, say you want to study WWRs as individual measures by cardinal direction (story, or section of a building are also scenarios we look ). If the measure groups were created by direction (0.2 WWR Group = 0.2 North Msr, 0.2East Msr... 0.3 WWR Group = 0.3 North Msr, 0.3 East Msr... ) and a whole building WWR Design Alternative was desired, it seems logical to just combine the measures within the one group. It is not that big of a deal to use a different structure, just something for users to think about when developing their measure groups.

DavidReddy's avatar DavidReddy  ( 2015-07-15 11:02:47 -0600 )edit

I certainly see your point, David. The PAT workflow was modeled on how practitioners were working within Xcel Energy's savings by design program, and it may not be optimal for all situations. That said, PAT's functionality will be expanded significantly in FY16, and it should support many more workflows. We'll be requesting input and design document feedback once that process kicks off in October.

ljbrackney's avatar ljbrackney  ( 2015-07-15 13:51:19 -0600 )edit

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Asked: 2015-07-14 19:58:44 -0600

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Last updated: Jul 14 '15