Extract zone CO2 concentration


I’m trying to extract zone CO2 concentrations in energyPlus by adding additional outputs to the Idf file… EP seems to run fine but I can’t see how to extract it from the results file. Has anybody else tried similar and got any tips?

Unfortunately I’m a new user so can’t upload files but have added a download link here.


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Are you modelling natural ventilation (opening windows) in which case I have an example of setting the number of people indoors (producing CO2) and Setting the outdoor Ppm for CO2.

This may be enough?


I’ve found the solution. It was working fine, just needed to use the ‘honeybee read ep custom result’ component.

Hey, could you share a screenshot of your solution? I would like to use it in my model as well :innocent:

Hey Tessa

Does this help?


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Yes, thank you very much!

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Unfortunately, I have not yet been able to get it to work for me. Could you possibly share your file with me so I can compare it to my file? Thank you so much in advance!

Let me know how you go with the attached :slight_smile:

CO2_Extract.gh (86.6 KB)

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Yes, Thank you very very much. This will help me finish my model for my graduation. Turns out I was not using the correct additional strings.

That would be very helpful, @MichaelDonn
I did my own script like @l.hewton just setting the ppm to zero in [ZoneAirContaminantBalance] to account people co2 only

Hello everyone, @l.hewton @chris

I was working with previous version of ladybug and honeybee and I was using an IDF for measuring CO2 concentration in the zone. Due to I need to come up with multizonal ventilation, I switched to employ the Ladybug tool to do the same simulations, but the IDF file does not work. Could anyone help me in this case? Infact I would like to know it is because of EnergyPlus version or the Openstudio’s additional string section?

Thank you in advance,

final.gh (762.5 KB)

Hi everyone,

I am working on version 1.5 of honeybee and ladybug and want to calculate the daily/monthly CO2 concentration in a honeybee room. Is there a way to do this in this newer version?

Thanks in advance.