Ladybug_AdaptiveComfortCalculator-Issue

Replies to This Discussion

Permalink Reply by Abraham Yezioro on June 21, 2015 at 12:59am

Alejandro,

The uploaded file is "faulty". You internalized the HB zone definitions and now the file is not recognizing the zones definitions, just the geometry.

-A.

Permalink Reply by Alejandro Gamas on June 21, 2015 at 7:07pm

Thanks Abraham,

By checking the definition, I actually realized that I was overlooking the fact that the zones were set as "conditioned", which was enabling the ideal air loads to take care of indoor temperature.

I changed it and things are clearer, yet now I became intrigued by a discrepancy between what is reported by the "conditionOfPerson" and the "percentOfTimeComfortable" outputs. At first glance would seem that they are reporting the same thing in different manner, but they both provide different outcomes (See pic). 

Why is that the case?

Shouldn´t the "conditionOfPerson" output had to incorporate the values within the threshold of 80 or 90% (in case that is not happening)?

Any comments?...

PD: The AdaptiveComfortChart doesn´t provide any output data. Not that I wan´t to rush any one out to fix it, but I just want to report it.

Thanks!,

Alejandro

 

Attachments:

• AdaptiveComfortCalculator2.gh, 582 KB

Permalink Reply by Chris Mackey on June 21, 2015 at 9:48pm

Alejandro,

All answers to your questions can be found in my response below.  The adaptive comfort chart does not provide any output data because it is still a WIP.  As I mention below, it should be out of WIP by the next stable release at the end of July.

-Chris

Permalink Reply by Chris Mackey on June 21, 2015 at 6:17pm

Hi Alejandro,

The reason why you don't get values adding to 100 is because the original ASHRAE adaptive standard states that you are not supposed to use the adaptive model when the average monthly temperature is below 10C and you are instead supposed to use the PMV model in theses cases.  However, there is plenty of research that has applied the adaptive methodology to monthly temperatures that are below 10C and the correlations produced by this research are what you are seeing in the WIP adaptive chart.  Here is a recent publication showing these correlations as well (http://nceub.commoncense.info/uploads/22-01-05-Humphreys.pdf).

To clarify further why the percents on the component are not adding to 100, the percentOfTimeComfortable is always calculated for the whole year (including the months where the average outdoor temperature it is below 10C) and uses the correlations found in new research to determine a target temperature for these very cold months.  So this percentOfTimeComfortable corresponds to the comfortableOrNot list coming out of the component.  The percentHotColdAndExtreme is calculated counting the months where the average outdoor temperature it is below 10C as "extreme" and so comfortable hours in this extreme time are added to the percentOfTimeComfortable but not the percentHotColdAndExtreme's comfortable hours.  In other words, this percentHotColdAndExtreme corresponds to the conditionOfPerson list coming out of the component.

Personally, I find the expectations of ASHRAE to switch between Adaptive and PMV models for a cooler climate like New York's to be unreasonable, especially given the correlations found in new research.  I have wanted to switch Ladybug's Adaptive model over to one that uses these new correlations in every case (without a cold extreme period) but I did not want to place myself above the building code without good reasons.  Now that I see that it causes confusion on the forums here and I have tested myself to see that the new adaptive correlations for temperatures below 10C are closely in line with the PMV model anyway, I have decided to push ahead with this switch.  Attached, you can find a GH model with this change and the percents now total 100.

If anyone is concerned about strictly following ASHRAE, you can easily calculate average monthly temperature for a climate with the Ladybug_AverageData component and simply not use the adaptive model for those months.  Alternatively, you can use only the adaptive model in early design for your own sanity of not switching between comfort models and, if you have to later show code compliance, I have found that you can almost always get the hours that use the wintertime adaptive correlations to work with the PMV model by playing around with the clothing and metabolic rates.  ASHRAE has ignored this really useful research on the adaptive methodology for conditioned buildings for too long and, if they aren't going to revise the standard to account for it, it is about time that practitioners pushed them to.

I am going to be re-vamping of the adaptive chart up to the point that it gets out of WIP for the next stable release.  This re-vamping will also include correlations for air conditioned and mixed-mode buildings that are also not yet accounted for in the ASHRAE Adaptive standard.  I will keep you posted.

-Chris

Attachments:

• AdaptiveComfortCalculator_CWM.gh, 557 KB

Permalink Reply by Alejandro Gamas on June 22, 2015 at 1:10am

Hi Chris,

Thanks a lot for the comprehensive explanation and for sharing the resources!

I agree that the current adaptive standard feels a little tight and oversimplified.

Another argument of debate would be the fact of having 12 reference values (monthly means), to determine the comfort temperature for 365 days, where daily mean temperatures could be drastically different from one day to the other. It would be interesting to see how many more drops could be squeezed from the lemon of passive conditioning if using daily means instead monthly to get the adaptive comfort ranges in the year. But I guess that´s a whole different discussion.

Suerte en todo,

Alejandro

Permalink Reply by Mostapha Sadeghipour Roudsari on June 22, 2015 at 3:17am

If anyone is concerned about strictly following ASHRAE, you can easily calculate average monthly temperature for a climate with the Ladybug_AverageData component and simply not use the adaptive model for those months.  Alternatively, you can use only the adaptive model in early design for your own sanity of not switching between comfort models and, if you have to later show code compliance, I have found that you can almost always get the hours that use the wintertime adaptive correlations to work with the PMV model by playing around with the clothing and metabolic rates. 

Hey Chris, I agree with you and I can see your logic and I like your approach. My only suggestion would be to have a check for the input data and give a warning to the user if you are using the alternate method.

Permalink Reply by Alejandro Gamas on June 22, 2015 at 2:18am

Chris,

I tried the component that you send, I got some weird results with the hot conditions.

Hopefully it´s an easy fix.

Thanks!

Attachments:

• AdaptiveComfortCalculator3.gh, 565 KB

Permalink Reply by Chris Mackey on July 4, 2015 at 1:06pm

Alejandro,

I am sorry for responding so late.  It seems that you did not update LB_LB to the latest version in your attached GH file.  Below you can find a GH file where I have updated all of the components to the latest version and, as you can see, everything works fine:

Over the next week, I am going to be adding in several new capabilities to the Adaptive model in LB+HB that are not an official part of ASHRAE or ISO standards but they are endorsed by the experts and researchers who have helped build the standards.  Mostapha, I will be sure to have the component give a comment any time that these un-standardized methods are used and I will be clear that I have made them a part of LB because I have found these insights from new research to be particularly helpful to design processes for passive architecture.  Also, I think many of us recognize that both ASHRAE and ISO were initially founded to produce standards for conditioned or refrigerated spaces and that, understandably, they .  Among the features that I will be adding in:

1) You will have the option of using either the American ASHRAE adaptive model or the ISO EN-15251 model (see the CBE's comfort tool for a visual of the differences - http://comfort.cbe.berkeley.edu/).

2) In addition to a different comfort polygon, the European standard also uses a "running mean" outdoor temperature instead of the average monthly outdoor temperature.  This "running mean" is computed by looking at the average temperatures over the last week and weights each of the daily average temperatures by how recent it is.  This makes more sense to me than the ASHRAE method and addresses the issue that you bring up, Alejandro.  Needless to say, the updated adaptive model will allow you to use either a running mean or average monthly temperature with either the American or European polygon.

3) The WIP adaptive chart currently has an option for a "levelOfConditioning".  This input allows you to make use of research the was conducted along-side the initial development of the adaptive model, which showed that the findings did not contradict the PMV model when people were surveyed in fully conditioned buildings.  This parallel research ended up producing a different correlation between the outdoor and desired indoor temperatures and this correlation had a much shallower slope than the official adaptive model for fully naturally-ventilated buildings.  The levelOfConditioning allows you to make a custom correlation for full natural ventilation, full conditioning or (presumably) somewhere in between for a mixed-mode building.  This levelOfConditioning will become an official input for all LB components using the adaptive model (not just the chart at the moment).

At the end of all of this, I will put together a new video series on Adaptive comfort so that we are all on the same page about how to use the model.

-Chris

Attachments:

• AdaptiveComfortCalculator3_CWM.gh, 573 KB

Permalink Reply by Alejandro Gamas on July 6, 2015 at 10:50pm

Hi Chris,

That´s great, thanks for sharing!...and for expanding the frontiers of exploration towards a more sustainable built environment!,

Alejandro

Permalink Reply by Chris Mackey on July 8, 2015 at 9:41pm

Alejandro,

I am just letting you know that the re-vamp of the adaptive model is complete.  Now, all of the components related to adaptive comfort accept the input from a new "Adaptive Comfort Par" component.  This allows you to switch between American and European standards and gives you more freedom about what to do in the conditions that fall outside of those explicitly covered by the standards:

https://github.com/mostaphaRoudsari/ladybug/commit/418e642861145ca6...

Also, the adaptive comfort chart is now complete with all of its features and out of the WIP section:

https://github.com/mostaphaRoudsari/ladybug/commit/ccdf9a26d99ade20...

Enjoy!

-Chris

Permalink Reply by Alejandro Gamas on July 12, 2015 at 11:57pm

Cool, thanks Chris!