Heating setpoint decreased by 2°C but the overall energy requirenment increses
Hello, I have concern about getting the cooling and humidification load increased drastically for the model by decreasing heating setpoint by 2°C.
IDF - https://drive.google.com/drive/folder...
I have just changed the class list - Shcedule:Compact from
Schedule:Compact,
Htg-SetP-Sch, !- Name
Temperature, !- Schedule Type Limits Name
Through: 12/31, !- Field 1
For: Weekends HoliDay, !- Field 2
Until: 7:00, !- Field 3
16, !- Field 4
Until: 14:00, !- Field 5
16, !- Field 6
Until: 24:00, !- Field 7
16, !- Field 8
For: SummerDesignDay, !- Field 9
Until: 24:00, !- Field 10
16, !- Field 11
For: WinterDesignDay, !- Field 12
Until: 24:00, !- Field 13
21, !- Field 14
For: AllOtherDays, !- Field 15
Until: 5:00, !- Field 16
16, !- Field 17
Until: 6:00, !- Field 18
20, !- Field 19
Until: 20:00, !- Field 20
22, !- Field 21
Until: 24:00, !- Field 22
16; !- Field 23
to
Schedule:Compact,
Htg-SetP-Sch, !- Name
Temperature, !- Schedule Type Limits Name
Through: 12/31, !- Field 1
For: Weekends HoliDay, !- Field 2
Until: 7:00, !- Field 3
14, !- Field 4
Until: 14:00, !- Field 5
14, !- Field 6
Until: 24:00, !- Field 7
14, !- Field 8
For: SummerDesignDay, !- Field 9
Until: 24:00, !- Field 10
14, !- Field 11
For: WinterDesignDay, !- Field 12
Until: 24:00, !- Field 13
19, !- Field 14
For: AllOtherDays, !- Field 15
Until: 5:00, !- Field 16
14, !- Field 17
Until: 6:00, !- Field 18
18, !- Field 19
Until: 20:00, !- Field 20
20, !- Field 21
Until: 24:00, !- Field 22
14; !- Field 23
but instead of decreasing energy demand it increased because of the sharp rise in cooling and humidification demand, even though rest of the setpoints have not changed.
Why is the increased cooling load ?
KR, Yagnik
@Yagnik can you upload your model to Google Drive, Dropbox, etc. and then share a URL for others to download? That would help others provide better solutions.
@Aaron Boranian here is the google drive link and i have also updated in the question above. IDF - https://drive.google.com/drive/folder...
Hello @rraustad, I don't understand the behaviour of the model. if I decrease heating setpoints, why is there drastic increase in cooling demand that eventually the total energy demand remains same after the decrease in heating setpoints too ? please make it clear for me. I have added the IDF link too..
@Yagnik is it a cooling demand increase or a dehumidification demand increase? My first guess is the lower heating set point allows the cooling coil to drive down the zone temperature when dehumidification is required. This makes it harder for the coil to dehumidify and the cooling coil needs to work morer. If you change Controller:WaterCoil from TemperatureAndHumidityRatio to Temperature you should see the results you expect. Then you can investigate my guess/assumption.
Hello @rraustad, both the cooling and humidification load got increased when I decrease heating setpoint. in fact, cooling and humidification demand increases that much that over pass the previous total deamnd too, when model run on normal heating setpoint (before decresing). so my question is after lowering heating setpoint, why is the overall load get increaed ? I am doing this experiment to assess the imact of decreased setpoint and how can it affect on overall co2 emissions ? but surprisingly, I got increased overall demand.