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2020-06-22 16:54:29 -0600 commented answer Failed to export gbxml?

@David - Yes @Julien - Please use this link for both OSM files and both GBXML files. Also, Do I need to install OS 3.0

2020-06-22 16:53:22 -0600 commented answer Failed to export gbxml?

@David - Yes @ - Please use this link for both OSM files and both GBXML fi

2020-06-18 20:26:37 -0600 answered a question Failed to export gbxml?

As a short term solution for those experiencing this issue, the GBXML data exported from the SketchUp 2019 using OS V1.0

2020-06-18 12:07:48 -0600 edited question Failed to export gbxml?

Failed to export gbxml? Having trouble importing GBXML from Sketchup and OpenStudio into other modeling tools. I get a

2020-06-18 12:07:14 -0600 edited question Failed to export gbxml?

Failed to export gbxml? Having trouble importing GBXML from Sketchup and OpenStudio into other modeling tools. I get a

2020-06-18 11:33:53 -0600 asked a question Failed to export gbxml?

Failed to export gbxml? Having trouble importing GBXML from Sketchup and OpenStudio into other modeling tools. I get a

2017-10-01 10:07:26 -0600 received badge  Popular Question (source)
2016-11-30 13:36:52 -0600 commented answer Apply Measure Now - Measure Output reporting info

That was my plan B as well. I only need to review one measure, so I will just mumble and gripe for the meantime. Thanks again.

2016-11-30 12:57:29 -0600 commented answer Apply Measure Now - Measure Output reporting info

Thanks Eric. I did see that that particular measure has the capability, but for other intensive measures, it would be nice to simply copy/ paste the text out of the measure screen instead of relying on measure authors to provide that functionality each and every time. Just my opinion.

2016-11-30 11:18:56 -0600 asked a question Apply Measure Now - Measure Output reporting info

Is it possible to review at a later date the Apply Measure Now - Measure Output reporting information? Ie. I cannot find a way to save the reporting information or even copy/paste out to review later when applying measures.

This is not needed for simple measures, but for the DOE reference building and create 90.1 baseline building measures it would certainly help in troubleshooting and in verifying the measure output step by step.

Thanks, Nic

2016-04-12 18:02:04 -0600 marked best answer How do I determine the sky conditions when using EnergyPlus/ Radiance in OpenStudio

Is there a way to determine sky conditions for a given date and time as interpreted by EnergyPlus or the Radiance package for OpenStudio?

Basically, I have narrowed down all the other factors regarding showing compliance for LEED IEQc8.1 and this is the only thing I cannot seem to get my head around.

For now I am taking the Radiance output > Space101map.ill file in the\1-Ruby-0\out\files\in\model\radiance\output\ts\Space_101\maps folder and ascertaining whether the space meets 2 single-point in time (3/21 9am & 3pm) metric of 10/500fc.

I know that the weather file is used to generate the sky conditions, but is there an ouput that tells me the exact condition for the hours chosen? If so, is there a way to override that condition to what is considered a "clear-sky."


2016-03-28 14:49:43 -0600 marked best answer How is simple ventilation controlled when using ideal loads in OpenStudio?

I usually rely on ideal loads when modeling during the earliest stages of any design for evaluating architectural configurations and envelope considerations. I recently discovered that providing a schedule in the OS:DesignSpecifcation:OutdoorAir object does not apparently impact the energy associated with ventilation for a project. This is admittedly only a quick test, but I could not verify any changes at all in the ABUPS report when swapping out schedules.

Is there another controlling factor such as population or an "Hours of Operation" schedule that controls this say during unoccupied periods? For example, Trane Trace 700 controls system operation around a threshold of 5% population.

I see that the "Minimum Outdoor Air During Occupied Hours" reads 0.011 ACH for Simple Venitlation and the "Average Outdoor Air During Occupied Hours" reads 0.695 ACH for Simple Ventilation. Clearly something is controlling the OA rate. I just do not know what that variable is.

Lastly, where can I look to see the actual simple ventilation during a given timestep? Or, should I just give up on ideal loads if I am looking for this amount of feedback from the model?

Thanks for any help.


2015-10-02 10:39:51 -0600 commented answer Multiple components for Air Distribution Unit

Appreciate the suggestion. I am interested in 8.4 for other reasons. I was using DesignBuilder, but will have to head into EPlus anyway to model desiccant dehumidification.

Only concern (as commented below) is the difficulty in reverse engineering the heat beam to act as a generic HW coil in the air stream. That is why I like the concept of the FCU with fan energy zeroed out. I'll try both to see which is the best fit. Right now the FCU has massive unmet hours.

2015-10-01 09:19:55 -0600 commented answer Multiple components for Air Distribution Unit

Thanks Aaron. I did look at the 4PipeInduction as an alternative since it is more fitting (over the central AHU reheat coil) with the zoning aspect of the branch reheat coil. My only concern there was whether or not it was a significant departure given the induction for both cooling and heating. Another solution was to zero out fan energy in a heating only FCU. I think I will try both and see what the outcome is. Thanks again.

2015-09-29 13:26:13 -0600 asked a question Multiple components for Air Distribution Unit

I am nearly convinced that simply modeling the system (diagram below) with in-zone equipment for reheat will be easiest, but I would like to see if anyone has feedback on alternative methods for modeling branch in-duct HW heating coils upstream of chilled-beams. Some zones also have perimeter HW radiant heating.

There is no simultaneous heating and cooling amongst the various downstream heating equipment and the chilled-beams.

Original Diagram (there is an inconsistency with the upstream supply fan location, but that is not at question.) C:\fakepath\AHU-1 Diagram.jpg

Alternative (Simple) method - radiant in-zone reheating equipment. C:\fakepath\AHU-1 Diagram - Simple.jpg

2015-09-11 16:19:19 -0600 received badge  Civic Duty (source)
2015-09-09 14:54:32 -0600 answered a question Can OpenStudio do LEED 62.1 multizone calcs?

I have not seriously attempted this with OpenStudio, but yes, there is an option to show compliance with Minimum Ventilation (VRP) using modeling software for LEED. I would caution that it is much more important that the air handling equipment schedule be the basis of the modeled ventilation rate rather than flicking the switch for VRP calculations in OpenStudio and toying around with the max Z ratio. The Min Ventilation credit is only to show that enough outdoor air is provided as scheduled. I have seen projects go through appeals in order to get this right.

I usually just fall back to using the 62MZCalc on suspected critical zones.

2015-09-03 14:57:50 -0600 commented answer Fan motor efficiency has no impact on energy consumption

If in reference to my post, sorry for any confusion. I was referring to a variance in heat gain based on the efficiency of the motor, not whether the motor was in/ out of the air stream. It does not appear to matter either way in David's answer since motor eff is already accounted for in Fan Total eff. It's just confusing now that it appears to prompt the user to account for motor eff twice. 1x in Tot eff and 1x in Mot eff.

2015-09-03 11:14:02 -0600 commented answer Fan motor efficiency has no impact on energy consumption

ANSWERED BY READING APARKER POST ABOVE. Would it impact the heat gain to the air stream if the motor efficiency became a referenced input along with the impeller eff? According to the OP simulation results, it appears that the current input for motor eff does not influence the rate of heat gain. (Correct me if I'm wrong.)

2015-08-21 16:41:16 -0600 received badge  Autobiographer
2015-08-21 11:55:00 -0600 commented answer VRF with variable fresh air supply

I sort of expected to hear this since the approach above models OA direct to the zones instead of upstream of the indoor unit as is the case with Richard's answer above. It appears that there is not a way currently to complete this in the OpenStudio application unless you create a measure.

Do you find this a common system design (without DOAS/ ERV)?

2015-08-20 10:25:55 -0600 commented question Does EnergyPlus need to be validated against DOE 2.2?

Learning opportunity for the reviewer:

Just out of curiosity, did the reviewer ask for the performance curve creation inputs (if you did not already supply them for the submission)?

2015-08-20 10:06:58 -0600 answered a question VRF with variable fresh air supply

Caution! Wild assumptions below.

Would it not be possible in OpenStudio to set up an Empty Air Loop without any coils such as an ERV (DOAS) system serving each VRF indoor unit? Obviously, the ERV would not be added to describe the system above. The fan and the AirLoopHVC Outdoor Air System are are the key objects you need. It should not matter, but is the indoor unit supply fan variable speed as well, or is it constant?

There is an attempt to model an ERV (DOAS) in OpenStuio in this forum question:

That post is discussing an ERV (DOAS) providing tempered or even conditioned outdoor air to each VRF indoor unit, which is common practice in my experience. There were errors, according to the original poster, when the loop was modeled without a setpoint manager. I am not sure how you could work around that issue if you are providing raw unconditioned air directly to the indoor unit, unless you ignore the many warnings/ errors associated with a loop setpoint manager without anything to manage. You could always schedule "OFF" the coils you place in order to get the simulation to run, but the warnings will likely be monstrous.

UPDATE: There is a MassFlowRate setting under Setpoint Manager Scheduled - Scheduled Deck Temp for the Control Variable. I am not sure if this fixes the fatal errors that are likely without the manager, but a good place to start.

2015-08-14 16:00:29 -0600 edited question Details about DOE commercial reference buildings

I can tell that the DOE reference buildings were created with data from 2003 CBECS. I am wondering how the individual space types were assigned. For example, the reference building for secondary school uses an air cooled chiller and packaged single zone units. I do not understand what rationale the modelers had for placing each HVAC type where? Why are certain space types cooled by the chiller, but others by the single zone units? How would I find this information? I am interested because I have to interchange HVAC equipment from these reference buildings, and would like some reference for where to put what types of HVAC in a building on a space type level of detail.

2015-08-04 11:49:09 -0600 answered a question Modeling plenum and handling floor thickness

I believe I remember seeing a method a few years ago in a simulation class for eQuest where the instructor modeled the FLR-FLR height as follows:

  1. Conditioned Zone (ToF to BoPlenum)
  2. Unconditioned Plenum (BoPlenum to BoSlab) Slab being the next level'sfloor/ roof deck
  3. UnconditionedPlenum (BoSlab to ToF) This is the floor thickness between two levels and completes the FLR-FLR dimension.

This way you get the correct volume for plenum and zone & the correct-ish surface transfer and height location for the construction accounting for any difference in insulation where the slab meets the exterior wall.

This always seemed like a lot of work when I saw it originally, but would be interesting to test the two cases.

P.S. I know DesignBuilder allows the user to draw the geometry based on Exterior Surfaces (walls, roof, floors, etc.) and then by way of construction assembly thickness can either simulate the "inner" (net) or "outer" (gross) floor areas, surface areas, and volumes indepently. But that is another skinned cat.

2015-07-31 07:37:33 -0600 marked best answer Warning - Calculated Relative Humidity out of range

I am constantly seeing this warning:

* Warning * Calculated Relative Humidity out of range (PsyRhFnTdbWPb) * ~~~ * Routine=CalcMultiSpeedDXCoil:lowspeedoutlet, Environment=RUN PERIOD 1, at Simulation time=04/12 13:00 - 13:10 * ~~~ * Dry-Bulb= 3.21 Humidity Ratio= 4.897E-003 Calculated Relative Humidity [%]= 101.01 * ~~~ * Relative Humidity being reset to 100.0%

Any thoughts on if this is something I can ignore?