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Where can I change the site to source conversion factors?

asked 2016-04-19 15:19:56 -0500

JM's avatar

updated 2016-04-19 15:50:58 -0500

Hey, could anyone tell me where I can change the conversion factors for electricity and district heating?

Several conversion factors are shown at the end of the Result Summary tab but I cannot find the place where I can change them. Thank you in advance!

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answered 2016-04-20 09:39:03 -0500

updated 2016-04-20 09:47:53 -0500

The values you see in the standard report are default values for EnergyPlus. You can alter them using Fuel Factor objects.

FuelFactor objects are not currently directly supported in OpenStudio, so you would have to add these with an EnergyPlus measure. A valid concern I often hear when I mention this is that someone doesn't know how to or have the time to write an EnergyPlus measure if one doesn't already exist, and I don't think there is one for Fuel Factors.

But there is a very simple solution for this. There is measure on BCL named Inject IDF Objects. It takes a single argument of the path to the IDF object you want to import.

First download that measure, then make an IDF file, for example one named "MyFuelFactors.idf" that looks something like what is shown below.

FuelFactors,                 !  USA national average based on eGRID, EIA 1605
Electricity,             !- Existing Fuel Resource Name
kg,                      !- Units of Measure (kg or m3)
,                        !- Energy per Unit Factor
2.253,                   !- Source Energy Factor {J/J}
,                        !- Source Energy Schedule Name
168.33317,               !- CO2 Emission Factor {g/MJ}
,                        !- CO2 Emission Factor Schedule Name
4.20616E-02,             !- CO Emission Factor {g/MJ}
,                        !- CO Emission Factor Schedule Name
1.39858E-03,             !- CH4 Emission Factor {g/MJ}
,                        !- CH4 Emission Factor Schedule Name
4.10753E-01,             !- NOx Emission Factor {g/MJ}
,                        !- NOx Emission Factor Schedule Name
2.41916E-03,             !- N2O Emission Factor {g/MJ}
,                        !- N2O Emission Factor Schedule Name
8.65731E-01,             !- SO2 Emission Factor {g/MJ}
,                        !- SO2 Emission Factor Schedule Name
2.95827E-02,             !- PM Emission Factor {g/MJ}
,                        !- PM Emission Factor Schedule Name
1.80450E-02,             !- PM10 Emission Factor {g/MJ}
,                        !- PM10 Emission Factor Schedule Name
1.15377E-02,             !- PM2.5 Emission Factor {g/MJ}
,                        !- PM2.5 Emission Factor Schedule Name
1.10837E-03,             !- NH3 Emission Factor {g/MJ}
,                        !- NH3 Emission Factor Schedule Name
3.72332E-03,             !- NMVOC Emission Factor {g/MJ}
,                        !- NMVOC Emission Factor Schedule Name
3.36414E-06,             !- Hg Emission Factor {g/MJ}
,                        !- Hg Emission Factor Schedule Name
0,                       !- Pb Emission Factor {g/MJ}
,                        !- Pb Emission Factor Schedule Name
2.10074,                 !- Water Emission Factor {L/MJ}
,                        !- Water Emission Factor Schedule Name
0,                       !- Nuclear High Level Emission Factor {g/MJ}
,                        !- Nuclear High Level Emission Factor Schedule Name
0;                       !- Nuclear Low Level Emission Factor {m3/MJ}

Then run the "Inject IDF Objects" measure with the argument set to the path to "MyFuelFactors.idf". That file can contain one or many IDF objects. You can use this measure anytime you want to just add objects vs. altering existing objects. And since the path is an argument you can use it for a parametric study by selecting from a pool of possible IDF files.

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Also, source to site conversion factors for district heating, district cooling and steam are entered using the EnvironmentalImpactFactors object.

ericringold's avatar ericringold  ( 2016-04-20 09:49:24 -0500 )edit

Thank you so much. However, I am an absolute beginner with OS and e+. Could you tell me where or how I can make an IDF file? And I am only interested in changing the conversation factor for district heating to 1,0 (type of energy supply for DHW and heating) and the factor of electricity to 2,5 (lighting and equipment). Is it correct if the IDF file would look like this? FuelFactors, ! My fuel factor 2.5, !- Source Energy Factor {J/J} 1.0 !- Electricity Energy Factor {J/J}

JM's avatar JM  ( 2016-04-20 10:27:50 -0500 )edit

hi David, how can I find this measure back. Or there is another method to set the Fuel Factors

Yi's avatar Yi  ( 2021-10-29 11:00:24 -0500 )edit

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Asked: 2016-04-19 15:19:56 -0500

Seen: 1,084 times

Last updated: Apr 20 '16