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How calculate time of high CO2 concentration?

asked 2022-06-25 17:03:52 -0600

K1nateghi's avatar

updated 2022-06-27 15:42:24 -0600

Hi, Is it possible to find the time (in minute or hour) that the CO2 concentration is higher than for ex 1500 ppm, during run period?

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answered 2022-06-27 06:37:32 -0600

In my opinion you shall report the CO2 concentration at hourly interval and then using excel you can easily identify when is higher than 1500 ppm (or directly on the graph)

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Thanks for the reply, Actually, I need only one number as an output to use in JEPlus+EA to optimize this value. JEPlus only accept one specific number as an output.

K1nateghi's avatar K1nateghi  ( 2022-06-27 06:43:07 -0600 )edit

answered 2022-06-27 10:20:59 -0600

You can use the Output:Table:Annual object where you specify "Maximum" for the Aggregation Type field. This will tell you both the maximum value and the time the maximum value occurred.

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Thanks for the suggestion. I think it would be useful. Is it possible to tell us the duration that the co2 concentration is more than a specific value in the run period? For example, 2 hours of the whole day, co2 concentration will be higher than 1500 ppm.

K1nateghi's avatar K1nateghi  ( 2022-06-27 10:32:11 -0600 )edit

Ah, sorry, I misunderstood that you want duration, not an instantaneous time. I think the only way to achieve this is to create an EMS program with a variable that increments when the CO2 concentration is above 1500. You could then request that EMS variable as an annual output variable. I believe you would also need to specify the EMS variable as an EnergyManagementSystem:GlobalVariable so that its value is preserved across each execution of the EMS program for a new timestep.

shorowit's avatar shorowit  ( 2022-06-27 11:02:34 -0600 )edit

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Asked: 2022-06-25 17:03:52 -0600

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Last updated: Jun 27 '22