JustinShultz's profile - activity

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?

Large Single Story Building HVAC Systems We have a 450,000 ft2 single story mental health hospital that we are energy mo

Large Single Story Building HVAC Systems I have a 450,000 ft2 single story mental health hospital that we are energy mod

Thanks for sharing the baseline_model.rb files in lib. That seems incredibly powerful for quick setups. Thank you for

These are very helpful examples. Thank you for sharing them! I'll see if I can convert them to python for my application

Thank you for the suggestion. I was also looking for a Type method for the coils. Is there a similar method?

Does the addToNode(Node&) method required the creation of the splitters and mixers and other node components or are

I have 100 plus Coil:Heating:Water components that I would like to connect to the Heating Hot Water Plant Loop. Is there a method in the OpenStudio SDK for connecting a coil object to the plant loop object?

I think there is a way to do this in the SDK but I'm having trouble figuring out the method. I have returned a list of the coils and plant loops but can't figure out how to connect them. Examples in python would be my preference but others are welcome.

I was able to figure out the answer to this question. Though if others come up with a more creative solution, let me kno

I was able to figure out the answer to this question. Though if others come up with a more creative solution, let me kno

OpenStudio SDK Connect Coil to PlantLoop I have 100 plus Coil:Heating:Water components that I would like to connect to t

Hello,

I'm a bit confused regarding the wording of EnergyPlus's description for OtherEquipment. The part that confuses me is:

"Note, too, that this object does not have an end-use component - gains or losses do not show up in the bottom energy lines (except as influencing overall zone gains or losses)."

Does this mean that it will only affect the overall zone gains and losses in the output with no impact to HVAC loads (energy use) or will the affect on zone balance then eventually affect HVAC loads for the respective zone?

Thank you, Justin

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?

That is a really good tip! I didn't realize that render by thermal zone would select the thermal zones. I'll try another

I am attempting to write a Sketchup Measure that takes the selected Thermal Zones and applies a Multiplier to them from a user input.

The code is below but I am having two problems:

• (Solved) I am getting an end-of-file error that I can't figure out.
  • I discovered that a next if does not require an end.
• Defining the multiplier to the thermal zone is not working. I don't believe my method is correct.

I iterate through each thermal zone and try to override the multiplier using:

thermal_zone.multiplier = 2

Is this the correct method or does it operate more like:

thermal_zone.multiplier(2)

I have also tried:

thermal_zone.setMultiplier(2)

My code can be found here GitHub

EDIT 10/15/2019

The script is now working and can be found at the above GitHub link. The solution was a combination of factors. @Julien Marrec answer below helped find several errors and troubleshoot.

The biggest mistake was that it doesn't appear the runner.isSelection() works on thermal zones in SketchUp as the interface is highlighting spaces, not thermal zones.

Instead, I had to use the runner.isSelection() on a space and then get the thermal zone for that space. After getting the thermal zone I could use the .setMultiplier(int) function that @Julien Marrec highlighted.

SketchUp Measure Multiplier to Selected Thermal Zones I am attempting to write a Sketchup Measure that takes the selecte

SketchUp Measure Multiplier to Selected Thermal Zones I am attempting to write a Sketchup Measure that takes the selecte

SketchUp Measure Multiplier to Selected Thermal Zones I am attempting to write a Sketchup Measure that takes the selecte

SketchUp Measure Multiplier to Selected Thermal Zones I am attempting to write a Sketchup Measure that takes the selecte

SketchUp Measure Multiplier to Selected Thermal Zones I am attempting to write a Sketchup Measure that takes the selecte

I am modeling a fairly tall building with a booster pump that supplies pressured cold water to the building and make-up water to the water heater. I realized that the booster pump in the design could be a pretty significant load on the building but I couldn't find a way to model the cold side of a domestic hot water loop.

Is there a component in OpenStudio or EnergyPlus that represent the supply of cold water to the building that would capture the energy consumption of the booster pump?

How to Model a Cold Water Booster Pump for Service Hot Water Demand? I am modeling a fairly tall building with a booster

@rraustad thank you very much for your response. I was not aware that the equation inputs could be found in the Energy+.

I have the same question. The Indoor Air Dry-Bulb Temperature does not apply to a WaterHeater:HeatPump, can we set the s

I am attempting to model an outdoor rest station with two large bathrooms. Based on ASHRAE 62.1 the restrooms have an exhaust airflow requirement of 70 cfm/toilet. Additionally, I am modulating the CFM by the occupancy schedule since there is very low occupancy during the winter.

In OpenStudio, I am using a Fan:ZoneExhaust object in each thermal zone with the Maximum Flow Rate option matching the CFM for the number of toilets. Using a 100% outside air system, I was hoping that the system would supply the correct amount of ventilation air to the space to supplement the exhausted air, without specifying any ventilation requirements.

However, in the error report, I am receiving the message:

  ** Warning ** GetOAControllerInputs: Controller:MechanicalVentilation="CONTROLLER MECHANICAL VENTILATION 1
  **   ~~~   ** Cannot locate a matching DesignSpecification:OutdoorAir object for Zone="THERMAL ZONE: 1 FEMALE RESTROOM".
  **   ~~~   ** Using default OA of 0.00944 m3/s-person and 0.0 m3/s-m2.

and

   ** Severe  ** Controller:MechanicalVentilation="CONTROLLER MECHANICAL VENTILATION 1", Design Specification Outdoor Air Object Name blank
   **   ~~~   ** For Zone="THERMAL ZONE: 2 MALE RESTROOM".
   **   ~~~   ** This field either needs to be filled in in this object or Sizing:Zone object.
   **   ~~~   ** For this run, default values for these fields will be used.

Which appears to be applying a Design Specified Outdoor Air that doesn't really balance with the Fan:ZoneExhaust object.

My question is, using the Fan:ZoneExhaust object with the Decoupled mode and Unbalanced (as seen in the documentation), is my fan being properly balanced with the 100% OA packaged rooftop system?

Should I specify a 0 DesignSpecification:OutdoorAir or will this incorrectly size my system?

What is the best method to balance my ventilation and exhaust flowrates for these spaces?

What about when I add energy recovery ventilation? How do I force the exhaust air back to my central system while keeping the correct ventilation requirements for the restroom?

Hi @lutinfr, can you please elaborate how I can change my calculation method to ASHRAE in IESVE?

Hi Giorgio, troubleshooting that kind of problem becomes more challenging without additional information. I would recomm

I have done this with other systems and found the best method is through the use of a plant loop with a PlantComponent:T

I have done this with other systems and found the best method is through the use of a plant loop with a PlantComponent:T

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.

I have just started using OpenStudio on a 4k monitor and found that the graphical user interface elements do not appear to be scaling correctly. All of the buttons are super tiny and hard to click.

Is there a setting or configuration file I can change to scale the interface elements?

Hello Modeling Community,

I have set up a small building model (<2300m2) with zones for each of the interior rooms. After setting up the geometry I wanted to configure a baseline following ASHRAE 90.1-2010, which recommends a Packaged Rooftop Heat Pump system. I set up a Packaged Rooftop Heat Pump system in OpenStudio, replacing the SingleZone setpoint manager with a Scheduled:DualSetpoint manager. After a lot of head scratching and model iterations I discovered that the EnergyPlus documentation for the HVACTemplate:System:UnitaryHeatPump:AirToAir states:

This system may serve one or more HVACTemplate:Zone:Unitary objects. If this system serves more than one zone, only one zone is specified as the control zone.

Which may explain why my system was not properly autosizing for the entire building.

So my questions are:

1. How do I setup a packaged rooftop heat pump system for a multizone building?
2. Can I use the packaged rooftop heat pump system as a preheater/precooler and at the zone level use heating and cooling diffusers? Does this still follow ASHRAE 90.1-2010?
3. Is it possible to autosize a packaged rooftop heat pump system for a building with multiple zones?
4. Are there alternative systems I could consider for a baseline?

Thank you for your time,

Justin