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How to implement Gas Combined Heat and Power CHP system in HVAC using OpenStudio

asked 2018-08-24 07:02:43 -0500

updated 2018-09-06 10:52:01 -0500

Hi,

I am currently trying to simulate a building powered by CHP unit. But I actually have no idea about how to do that in OS (that I have just started to learn how to use it), I read a lot of comments/answers to questions related to this topic, but I didn't understand much ..


While looking in my OS library I found this component:

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Is this the CHP unit that I should add in the loop? Or is it more complex?


I also read that I should add ElectricLoadCenter:Distribution and ElectricLoadCenter:Generators measures, but I couldn't find them in the BCL library and I still don't know how to write a measure. Does anyone have the measure and can share it with me ?

Any help would be most welcome... Thanks


Edit: Here are some screenshots for what I have done so far with Capstone C65 (the component above) but I cannot get it to turn on in the result report (it is like there is only the water heater and the boiler).

PlantLoop1

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PlantLoop2

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AirLoop

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answered 2018-09-06 13:18:38 -0500

mldichter gravatar image

First off, the ElectricLoadCenter:Distribution and ElectricLoadCenter:Generators are not measures, they are objects in energyplus. BCL measures typically add many objects to a model, like everything necessary to make a plant loop, which is quite a few energyplus objects. It is very unlikely someone made a measure to add those objects by themselves. They also need to be connected to relevant objects in the simulation.

That being said, I'm not sure how to add an ElectricLoadCenter:Distribution or ElectricLoadCenter:Generators object using Openstudio. In fact, Openstudio may be unable to handle those objects. Last I checked, Openstudio does not have all Energyplus objects implemented.

What I recommend is completing as much of your model in Openstudio, then File -> Export -> IDF your Openstudio model to a .idf file. You can double click the .idf file and use the IDF editor to add in the ElectricLoadCenter:Distribution, ElectricLoadCenter:Generators, and any other objects you need to complete the model.

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Then you can simulate, with whatever weather file you want, the idf file with the objects you've added.

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The simulation will probably fail the first time you try to run your idf file. Then you can take a look at the errors energyplus generated, which you can usually look up in the Input Output Reference, find the answer on unmet hours, or the error is self explanatory enough to find the problem.

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Then keep fixing the errors until your simulation actually runs, in which case you may still need to fix warnings, like water pipes freezing or hot water heaters overheating or hvac systems not cooling sufficiently or etc.

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@mldichter thank you for your reply, I did as you said, but since it is my first time using energyplus I couldn't assign the nodes correctly (I didn't know which nodes related to the capstoneC65 to put in the corresponding boxes) and now I got this error Severe ** Plant Component Generator:Microturbine called "CAPSTONE C65" was not found on any plant loops. ** ~~~ ** Component, type="Generator:Microturbine", name="CAPSTONE C65" was not found on any Branch. ** ~~~ ** Look for mistyped branch or component names/types.

Raghda Derbel gravatar imageRaghda Derbel ( 2018-09-13 08:27:59 -0500 )edit

@Raghda Derbel I have no idea.

Can you post a link to your idf file from dropbox, google drive, or whatever. Then I can download it and take a look.

mldichter gravatar imagemldichter ( 2018-09-14 15:09:03 -0500 )edit

@mldichter, Thank you, but I finally knew how to implement it correctly after several trials (it's my 1st time using e+ so I didn't know how to correctly assign the new branches & nodes related to the CHP) and now apparently I have to deal with the results of EnergyPlus, whereas I would very much like to still benefit from the results of OS Do you know if it's feasable?

Raghda Derbel gravatar imageRaghda Derbel ( 2018-09-14 16:30:09 -0500 )edit

@mldichter, I still have a problem though, concerning the number of CHP. I am supposed to simulate the building with one CHP, but it seems like I need to implement 2 different CHP because I have 2 plantloops as shown above (when I tried to use just one CHP in e+, the simulation failed saying that there is one component that has different nodes). So instead of using one CHP with a power of 15kW, I am using two units of 7.5kW each, but the results won't be accurate. Do you have any suggestion that could help me with this ? PS: if you still want to check the idf, can I send it to you privately?

Raghda Derbel gravatar imageRaghda Derbel ( 2018-09-14 16:42:33 -0500 )edit

I just asked a question about that here

Raghda Derbel gravatar imageRaghda Derbel ( 2018-09-14 16:59:59 -0500 )edit

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Asked: 2018-08-24 07:02:43 -0500

Seen: 252 times

Last updated: Sep 06 '18