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2016-09-24 22:22:56 -0600 asked a question Zone Conduction Gain and Solar Gain Output Variables

Hi everyone,

I'm not sure if this question has been asked yet. But I'm posting it for help from you guys.

In EnergyPlus, I'm trying to let it out put the following two variables:

  1. Zone,Sum,Zone Transmitted Solar Energy;
  2. Zone,Average,Zone Opaque Surface Inside Face Conduction;

But after reviewing the RDD file, doesn't seem I have these two variables available. So I guess even I add the variables in IDF file, it still won't output them because RDD file indicates they are not existed. Is there anything I need to specify in order to make these two variables be available for output?

In general, is this the way how you guys usually look at zone conduction gain and solar gain?

Thanks for the help!

2016-09-22 17:56:27 -0600 asked a question Setpoint Reset and Single Speed Cooling Coil Control

Hi everyone,

I have a question about supply air temperature reset and DX single speed coil. Hope you guys can provide me with some direction.

Basically, I have packaged rooftop unit. I use SetpointManger to reset the supply air temperature to 65 using warmest zone control. Now if I model a single speed DX coil, based on my understanding it will only cycle on/off when it is not full-load. In this case, will this ignore the supply air temperature reset if it's just turning off when it's at partial load?

Thanks!

2016-07-05 19:26:03 -0600 asked a question EnergyPlus Results File

Hi All,

Does anyone know how to view the EnergyPlus simulation result hourly loads data?

Specifically, I'm using CBECC-Com to run a simulation. It'll generate a .csv file for me which contains hourly "cooling energy" use. But how do I look at the hourly load? Further more, how do I look at the load for each room or each system?

In addition, it there a way to look at different load component such as solar gain, conduction gain, etc.?

Thanks!

2016-06-29 12:18:03 -0600 commented answer Hourly Data From CBECC-Com

Thanks for your help! I agree with all what you suggested about the design day issue. I was also able to get some help from CBECC-Com team. Actually what happens is that I was using "Quick Analysis" to run the simulation, and this option only runs four weeks in a year, one week per season to minimize the difference compare to a normal 8760 hours simulation. The option just allows people to run the simulation and detect errors quickly, I forgot to uncheck this when I run a normal simulation. I appreciate your help!

2016-06-29 00:16:18 -0600 commented answer "NR SBD Performance" calculation in Energy Pro

Thanks, Anna. You are right, the SBD non-compliance mode uses DOE-2, and it even use DOE-2 for compliance mode as well, which shows a significant difference compare to E+ compliance mode. I haven't had a chance to look deep into this, but I was able to make it pass by fix some parameters. Your help is appreciated.

2016-06-29 00:04:58 -0600 asked a question Hourly Data From CBECC-Com

Hi All,

I have a technical question regarding viewing the hourly data from Title 24 simulation from CBECC-Com (essentially E+).

After the simulation, I opened HourlyResults.csv file to view the hourly data. It is basically showing only couple days in a year, I have cooling/heating/lighting/equipment energy use. Except those days, the hourly data are all just "0". This is a little bit odd to me. I assume it has something to do with the internal load schedule because it is not only for HVAC but also happens to lighting and equipment. But, isn't Title 24 use default schedule for all the internal gains (even if I don't assign any schedule to the space, it will still use the default)?

Have any of you ever ran into this problem before? Please advice if there is something I should check.

Thanks!

2016-06-09 12:35:43 -0600 asked a question "NR SBD Performance" calculation in Energy Pro

Hi all,

I have a technical question about Energy Pro specifically. Have anyone used "NR SBD Performance" Savings By Design non-compliance mode calc in Energy Pro before? I was trying to run Savings By Design calc to get the percentage of savings, but the result seems to be ridiculous. The results from "NR T24 Performance" calculation seems fine, it is showing about 15% better than Title 24 baseline, but the "NR SBD Performance" calculation results doesn't make sense to me at all, it became 28% worse instead. The fan energy use is ridiculously high.

I know that the Title 24 performance module uses CBECC-Com, how about SBD? The SBD only took 1 second to pop up the results for me..

Thanks for you help!

2016-02-09 23:46:25 -0600 commented answer Daylight Control-Energy Pro

Thanks! Is the baseline lighting controlled by any other options rather than daylight? Since I have been seeing a lower lighting energy use for the baseline although the proposed LPD is 80% of the baseline LPD (I put luminaire in each room). Any reasons why that happens? Thanks!

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2016-02-09 20:10:16 -0600 asked a question Daylight Control-Energy Pro

Hi, does anyone know how to model daylight control in Energy Pro? There doesn't seem to be an option for daylight control for each luminaire, there are only "Occ Sensor-Partial On", "Dimming-Manual", "Demand Responsive" and other, but no daylight control.

Is there any way to model daylight control in Energy Pro?

Thanks!