Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question

JustinShultz's profile - activity

2018-08-07 10:51:59 -0500 commented answer OS Error:''For zone: it is not possible to calculate the volume from the surrounding surfaces so either provide the volume value or define all the surfaces to fully enclose the zone.''

@Raghda Derbel You are close but it would be more accurate to sum all the volumes and set that as the volume in the ther

2018-08-07 10:16:01 -0500 commented answer DView Loading Data Extremely Slowly

@anchapin please post the GitHub issue link when you do so that I can post my experience and keep track of the solution.

2018-08-07 08:02:13 -0500 commented answer OS Error:''For zone: it is not possible to calculate the volume from the surrounding surfaces so either provide the volume value or define all the surfaces to fully enclose the zone.''

@Raghda Derbel, you will need to define a new thermal zone for each kitchen.

2018-07-26 17:19:24 -0500 commented answer Best method to define individual space properties

Thank you for your answer. I should really learn Ruby and the OpenStudio SDK. It seems like I could automate a lot of my

2018-07-26 17:18:51 -0500 marked best answer Best method to define individual space properties

I am setting up an OpenStudio model for an architectural project and there are quite a lot of spaces where I have to define unique properties for occupancy and ventilation. More specifically they are labs with fume hoods.

I've defined high level information as space types and placed local properties onto the spaces in the "Spaces" tab. However, the space type definitions remain part of the calculations.

Space Load Properties

Zone Name        |  Floor Area {m2} | # Occupants | Area per Occ {m2/person}| Occ per Area {person/m2}  
THERMAL ZONE: 514 ADV CHEM TL    167.93    25.0           6.70                    0.15

Is there a way to override the space type properties when a local load has been defined in the "Spaces" tab?

What are the best methods and practices when it comes to defining properties for individual spaces in OpenStudio?

I found this old question here but it seems to no longer be relevant with new versions of OpenStudio.

2018-07-24 16:57:51 -0500 edited question Best method to define individual space properties

Best method to define individual space properties I am setting up an OpenStudio model for an architectural project and t

2018-07-24 16:56:45 -0500 asked a question Best method to define individual space properties

Best method to define individual space properties I am setting up an OpenStudio model for an architectural project and t

2018-07-24 16:39:35 -0500 commented answer Input people number in each space

I am hoping to define unique loads for many spaces throughout my building and assumed that a locally defining property w

2018-06-08 06:43:08 -0500 marked best answer OpenStudio Humidity Setpoint Not Met

Dear Modeling Community,

I have setup humidification and dehumidification setpoint schedules of always 35% and 70%, respectively. However, when checking the Zone Conditions Humidity table there are significant hours (~3750 hours) where the humidity is below 30%. This is strange because based on the setpoint the zone should not be allow to drop below 35%.

For context, the project is a Midrise Apartment so the occupancy doesn't drop down like office. I would suspect humidification to be necessary throughout most of the day.

I am using a PTHP, could it be that the system does not have any humidification/dehumidification functionality so although I have a schedule set there is no control to the humidity?

Any other suggestions why the humidity is uncontrolled in my space, despite defining setpoint schedules would be very appreciated.

Thank you, Justin

2018-06-01 09:47:10 -0500 commented answer COP of District Cooling Component

Thank you for your quick reply.

2018-06-01 09:47:01 -0500 marked best answer COP of District Cooling Component

I have recently run a simulation that used the DistrictCooling component to model a Central Chiller that is external to the building.

However, after reading the Engineering Reference Manual and Input/Output Manual, I am unable to determine if the energy consumption calculated from the District Cooling component accounts for a COP. My assumption is that the energy values are just that required to satisfy the demand, without a COP. Is that the case?

I would like to know so that I don't discount the energy consumed again if a COP was accounted.

2018-06-01 09:08:26 -0500 asked a question COP of District Cooling Component

COP of District Cooling Component I have recently run a simulation that used the DistrictCooling component to model a Ce

2018-05-30 09:00:35 -0500 commented answer OpenStudio/EnergyPlus Thermal Zone Outdoor Air Balance with Exhaust Fan Only and 100% Outside Air System

Thank you for your advice. I thought that might be the best solution, it is good to get confirmation. After specifying t

2018-05-30 08:57:50 -0500 commented answer OS Error:''For zone: it is not possible to calculate the volume from the surrounding surfaces so either provide the volume value or define all the surfaces to fully enclose the zone.''

For anyone interested in changing the volumes more quickly, you can also manually type in the volume into the *.osm file

2018-05-25 12:23:12 -0500 edited question Change IDF File After Setting Up OpenStudio Project

Change IDF File After Setting Up OpenStudio Proejct I started a new OpenStudio project in the SketchUp Plug-in by import

2018-05-25 12:22:15 -0500 edited question OpenStudio/EnergyPlus Thermal Zone Outdoor Air Balance with Exhaust Fan Only and 100% Outside Air System

OpenStudio/EnergyPlus Thermal Zone Outdoor Air Balance with Exhaust Fan Only and 100% Outside Air System I am attempting

2018-05-25 12:18:24 -0500 edited question OpenStudio/EnergyPlus Thermal Zone Outdoor Air Balance with Exhaust Fan Only and 100% Outside Air System

OpenStudio/EnergyPlus Thermal Zone Outdoor Air Balance with Exhaust Fan Only and 100% Outside Air System I am attempting

2018-05-25 12:15:47 -0500 edited question OpenStudio/EnergyPlus Thermal Zone Outdoor Air Balance with Exhaust Fan Only and 100% Outside Air System

OpenStudio/EnergyPlus Thermal Zone Outdoor Air Balance with Exhaust Fan Only and 100% Outside Air System I am attempting

2018-05-25 11:59:51 -0500 asked a question OpenStudio/EnergyPlus Thermal Zone Outdoor Air Balance with Exhaust Fan Only and 100% Outside Air System

OpenStudio/EnergyPlus Thermal Zone Outdoor Air Balance with Exhaust Fan Only and 100% Outside Air System I am attempting

2018-05-24 15:56:23 -0500 marked best answer Point of Use Electrical Hot Water Heater

What is the best way to model a Point of Use Electrical Hot Water Heater in OpenStudio?

I was thinking that I could setup several small electric hot water heaters with small water volumes and let them address the demand. Would this be appropriate or might there be a better solution?

2018-05-24 15:18:40 -0500 edited question Point of Use Electrical Hot Water Heater

Point of Use Electrical Hot Water Heater What is the best way to model a Point of Use Electrical Hot Water Heater in Ope

2018-05-24 15:18:11 -0500 asked a question Point of Use Electrical Hot Water Heater

Point of Use Electrical Hot Water Heater What is the best way to model a Point of Use Electrical Hot Water Heater in Ope

2018-05-18 10:46:08 -0500 marked best answer Access to Cold Water Supply Temperature for WaterUse:Equipment in OpenStudio

I have setup a WaterUse:Equipment component in my OpenStudio model following this tutorial. However, I would like to edit the Cold Water Supply Temperature Schedule Name input to the WaterUse:Equipment.

I am familiar with how to do this in EnergyPlus as it is simply the input below the Hot Water Supply Temperature Schedule Name, can you help me set this input within OpenStudio?

I noticed the WaterHeater:Mixed component has a Cold Water Supply Temperature Schedule Name that provides input to the boiler but the WaterUse:Equipment is not doing the proper mixing because the supply temperature is set to the default 10C.

Thank you,

Justin

Edit 1 I noticed that the Cold Water Supply Temperature Schedule Name for the WaterHeater:Mixed component does not appear to have an effect on the energy consumption of the Water Heater when elevating hotter or colder supply water. Am I missing something?

2018-04-04 08:39:50 -0500 edited question ASHRAE System for Server / Computer Room

ASHRAE System for Server Room I have a Baseline model with a server room. I was wondering what the prescribed system wou

2018-04-04 08:37:00 -0500 marked best answer ASHRAE System for Server / Computer Room

I have a Baseline model with a server room. I was wondering what the prescribed system would be following ASHRAE Appendix G?

A PTAC seems like the most straightforward answer but is there a baseline system type I should use for this space?

Currently the space is keeping a constantly load on the central chiller, producing 4000+ hour a year below a 10 percent part load, which is obviously unrealistic.

2018-04-04 08:36:59 -0500 commented answer ASHRAE System for Server / Computer Room

Thank you for your answer, this was the perfect response.

2018-04-03 17:08:14 -0500 commented answer Energyplus example error

The timestep in all the simulations need to match.

2018-04-03 17:06:42 -0500 asked a question ASHRAE System for Server / Computer Room

ASHRAE System for Server Room I have a Baseline model with a server room. I was wondering what the prescribed system wou

2018-03-28 10:31:00 -0500 marked best answer How does "autosized" work in EnergyPlus OpenStudio with External Inputs?

I am using a PlantComponent:TemperatureSource connected to a WaterHeater:Mixed which is then connected to a ZoneHVAC:Baseboard:Convective:Water. I had a few of these components set to autosize but realize they might not be receiving enough information during the design days. I am running the energy model in a co-simulation with another program that, during runtime, feeds in the temperature of the PlantComponent:TemperatureSource and the Mass Flow rate of a pump. Unfortunately, none of this information is passed during the design days.

My question is, how does EnergyPlus autosize equipment? Does it only look at the design days to find the most extreme conditions?

Additionally, because I'm not feeding in the temperature and flowrate values prior to the run period, is there anyway I can still have parts of the connected plant loops autosize?

2018-03-12 08:29:10 -0500 marked best answer DView Loading Data Extremely Slowly

OpenStudio now uses DView directly for data visualization instead of ResultsViewer. However, while trying to open data dview takes several minutes (sometimes 15 or more) just to open a small output file. Are there any fixes I can do to that will make this process faster?

In the meantime, I will likely need to use another results viewer because this is too slow.

2018-03-09 10:30:15 -0500 commented answer DView Loading Data Extremely Slowly

Hi Eric, I am on Windows 10. I am trying to open the sql file that is about 45mb and not converted to IP. Thank you for

2018-03-09 09:38:03 -0500 asked a question DView Loading Data Extremely Slowly

DView Loading Data Extremely Slowly OpenStudio now uses DView directly for data visualization instead of ResultsViewer.

2018-03-07 12:24:52 -0500 commented answer Heat Exchanger to Preheat Service/Domestic Hot Water

Julien, I am just seeing this response. Thank you for your time. I believe I understand now. It appears as though I can

2018-02-12 23:07:53 -0500 marked best answer FMU Export of Python Code or Python Interface with FMI Standard for Use in EnergyPlus Co-Simulation

My research group has developed python code for a new building component that we would like to co-simulate with EnergyPlus. For reuseability and market impact we would like this connection to be as easy as possible for inexperienced users and believe packing the model using the Function Mockup Interface Standard (FMI) to be the best option.

We have explored JModelica to test other Functional Mockup Units (FMUs) but found that it does not do FMU export of Python code for model exchange or co-simulation.

I was curious if there any methods for packaging python code as an FMU? If there is not, is there another way of linking Python to the FMI standard or connecting it to a building energy software like EnergyPlus?

The alternative to this would be exporting the building energy model as an FMU and import into modelica/jmodelica or using BCVTB. Although this would work for us we worry it would make it too difficult for inexperienced individuals to use our tool.

2018-02-12 13:49:00 -0500 commented answer What are some good programs/applications to use as a text editor for EnergyPlus models?

@eayoungs, would you mind uploading your syntax files again? The GitHub link you provided no longer appears to work. @

2017-12-07 09:46:41 -0500 commented answer Heat Exchanger to Preheat Service/Domestic Hot Water

I setup a PlantEquipmentList with the HX before the boiler but found that the HX still has no effect on reducing the nat

2017-12-06 19:22:11 -0500 commented answer Heat Exchanger to Preheat Service/Domestic Hot Water

I setup a PlantEquipmentList with the HX before the boiler but found that the HX still has no effect on reducing the nat