Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question
7

Is it possible to use real time sensor data (of temperature in- and outside, CO2 levels, occupancy) in EnergyPlus instead of Schedules?

asked 2019-03-19 05:30:46 -0500

Eline's avatar

updated 2019-03-20 09:24:12 -0500

Is it possible to use real time sensor data (of temperature in- and outside the building, CO2 levels, occupancy) in EnergyPlus instead of Schedules? If yes, how? Which program to use?

edit retag flag offensive close merge delete

Comments

You should be able to use EnergyPlus' EMS (Energy Management System) feature to do this.

__AmirRoth__'s avatar __AmirRoth__  ( 2019-03-20 09:29:36 -0500 )edit

3 Answers

Sort by » oldest newest most voted
6

answered 2019-03-20 16:23:10 -0500

You can do this with a combination of two objects in EnergyPlus:

The Schedule:File object can be used for the following items in your original post:

  • Temperature inside the building: The closest you can get is by setting the heating and cooling thermostat temperature schedules to your sensor data -- there is no way to directly set zone air temperature in EnergyPlus (not even with EMS). These thermostat temperature schedules are referenced by various ThermostatSetpoint:### objects
  • Occupancy: Occupancy schedule referenced by People objects

The EMS objects will be used to override:

  • Temperature outside the building: The EMS actuator for Outdoor Drybulb. You could also create a custom .epw weather file to use in your simulations, although that will require updating outdoor humidity and other data in the weather file to be truly accurate. This would require an EMS sensor to read a Schedule:File object of your sensor data for outdoor air temperatures. There's a separate EMS Guide document for EnergyPlus because of the extra complexity required to set up EMS objects.

I didn't list CO2 levels because that is ... tricky. The People object does have an input for CO2 Generation Rate, but that's the rate it's added to the zone from occupants -- not the overall CO2 levels in the zone. You may need to create a Demand Control Ventilation system that brings outdoor air into the zone to maintain a CO2 Parts Per Million setpoint (which you can set using a schedule, so the Schedule:File object could work).

edit flag offensive delete link more
1

answered 2019-12-06 08:47:13 -0500

Maria Alonso's avatar

Is it possible to use moisture measurements?

Otherwise, how would you add loads of humidity from people, plants, combustion, etc.? In my case, adding moisture loads as a latent source does not seem to be so correct as I can only add moisture from people in the best case. I am interested in calculating RH levels as a result of different ventilation strategies.

edit flag offensive delete link more

Comments

1

@Maria Alonso if this is a new question that you would like people to help with, please make a new post. To get more information about how to do that, you can visit the help page.

Aaron Boranian's avatar Aaron Boranian  ( 2019-12-06 10:06:51 -0500 )edit

Maria, I am trying to figure out how to model/report humidity from these sources too....ecspecially indoor plants/vegetation. Please let me know if you have made any progress with this. Thanks!

mechyai's avatar mechyai  ( 2021-04-02 00:31:05 -0500 )edit
1

Sorry for my late repply, I did not see it! Moisture transport can be modeled using EnergyPlus. The moisture production schedules can be defined in EnergyPlus as schedules connected to “OtherEquipment” to account for occupant-generated moisture.

Maria Alonso's avatar Maria Alonso  ( 2021-04-27 06:29:21 -0500 )edit
1

answered 2019-03-25 07:13:05 -0500

You can also use the Building Controls Virtual Test Bed (BCVTB) to link-in real time sensor data from BACnet compliant BAS. Similar to Aaron's answer, you'll need to use EMS objects in EnergyPlus to override normal EnergyPlus behavior. But BCVTB gives the ability to pull-in real time data instead of referencing a static Schedule:File.

Although, be warned that BCVTB hasn't been updated since April 2016. It's been a while since I tried using it and I'm not sure how well it works anymore. Also, it is compatible with EnergyPlus 8.5.

edit flag offensive delete link more

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Training Workshops

Question Tools

4 followers

Stats

Asked: 2019-03-19 05:30:46 -0500

Seen: 534 times

Last updated: Mar 25 '19