I think you should compare the output at different report time to compare.
Zone means for the whole zone or zone specific.
Average means that the value is averaged from the base calculated data.
These are not the official EPlus definitions. I observed some of these when doing the RVI example, where the spread sheet has the timestep, hourly, monthly and annual values.
For example, the OD temperature has one hour as the input interval. It is interpolated linearly for calculation at timesteps. The zone OA can also varies with height. So you have the zone value, the averaged value when the output is listed hourly again.
The input OA has only one decimal point, the output OA has more than one decimal points,even when listed as hourly. The WinterDesignDay values are not changed, because the range is zero at the input..
When you ask for daily, monthly, and yearly values, the output are all averaged values from the base data.
When I suggest that you should try to verify using the different time, is try to do the averaging yourself using different output data at different intervals.
"to multiply 190 w/m2 by 8760 hrs to obtain a value of 1664 kWh/m2 per year" is probably correct.
However, you can also ask for monthly average and average again to see whether the answer is also close to 190 w/m2. The number will not be exact, due to decimal point conversion error, etc.
For tropical countries where the solar incidence value does not change very much, the different numer of days in a month (28 and 31 days) did show some differencec, in the monthly listing.
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
From: ooi_kb3@xxxxxxxxxxx
Date: Sat, 25 Jun 2011 07:31:18 +0000
Subject: [EnergyPlus_Support] Re: Surface Incident Solar Radiation
--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, Ng Poh Khai <ng_khai@...> wrote:
>
>
>
>
>
>
Hi Poh Keat,
i followed your paras 1 and 2 and have the same question as in your para 3.
i believe your para 5 is correct. i have checked that for other variables during my work with EnergyPlus
all the best
ooi
> Dear All,
>
> I am trying to obtain the incident solar radiation for exterior surfaces such as the exterior walls (various directions) and roof.
>
> I understand that there is an output named: Surface Ext Solar Incident under the Output:Variable. I checked the EnergyPlus Main Documentation and it was listed as Zone,Average,Surface Ext Solar Incident [W/m2].
>
> What does the "Zone" and "Average" mean? Does "Average" means that the value given from the simulation is the average of the run period?
>
> I specified the run period to be an entire year and taking the output for my roof, it was 190w/m2.
>
> Does it mean that in order for me to determine the annual total solar incident energy, I will need to multiply 190 w/m2 by 8760 hrs to obtain a value of 1664 kWh/m2 per year?
>
> Thanks in advance for any feedbacks and suggestions.
>
> Best Regards,
> Ng Poh Khai
>
__._,_.___
Primary EnergyPlus support is found at:
http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx
The primary EnergyPlus web site is found at:
http://www.energyplus.gov
The group web site is:
http://groups.yahoo.com/group/EnergyPlus_Support/
Attachments are currently allowed but be mindful that not everyone has a high speed connection. Limit attachments to small files.
EnergyPlus Documentation is searchable. Open EPlusMainMenu.pdf under the Documentation link and press the "search" button.
![]()
__,_._,___
Zone means for the whole zone or zone specific.
Average means that the value is averaged from the base calculated data.
These are not the official EPlus definitions. I observed some of these when doing the RVI example, where the spread sheet has the timestep, hourly, monthly and annual values.
For example, the OD temperature has one hour as the input interval. It is interpolated linearly for calculation at timesteps. The zone OA can also varies with height. So you have the zone value, the averaged value when the output is listed hourly again.
The input OA has only one decimal point, the output OA has more than one decimal points,even when listed as hourly. The WinterDesignDay values are not changed, because the range is zero at the input..
When you ask for daily, monthly, and yearly values, the output are all averaged values from the base data.
When I suggest that you should try to verify using the different time, is try to do the averaging yourself using different output data at different intervals.
"to multiply 190 w/m2 by 8760 hrs to obtain a value of 1664 kWh/m2 per year" is probably correct.
However, you can also ask for monthly average and average again to see whether the answer is also close to 190 w/m2. The number will not be exact, due to decimal point conversion error, etc.
For tropical countries where the solar incidence value does not change very much, the different numer of days in a month (28 and 31 days) did show some differencec, in the monthly listing.
Dr. Li
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
From: ooi_kb3@xxxxxxxxxxx
Date: Sat, 25 Jun 2011 07:31:18 +0000
Subject: [EnergyPlus_Support] Re: Surface Incident Solar Radiation
--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, Ng Poh Khai <ng_khai@...> wrote:
>
>
>
>
>
>
Hi Poh Keat,
i followed your paras 1 and 2 and have the same question as in your para 3.
i believe your para 5 is correct. i have checked that for other variables during my work with EnergyPlus
all the best
ooi
> Dear All,
>
> I am trying to obtain the incident solar radiation for exterior surfaces such as the exterior walls (various directions) and roof.
>
> I understand that there is an output named: Surface Ext Solar Incident under the Output:Variable. I checked the EnergyPlus Main Documentation and it was listed as Zone,Average,Surface Ext Solar Incident [W/m2].
>
> What does the "Zone" and "Average" mean? Does "Average" means that the value given from the simulation is the average of the run period?
>
> I specified the run period to be an entire year and taking the output for my roof, it was 190w/m2.
>
> Does it mean that in order for me to determine the annual total solar incident energy, I will need to multiply 190 w/m2 by 8760 hrs to obtain a value of 1664 kWh/m2 per year?
>
> Thanks in advance for any feedbacks and suggestions.
>
> Best Regards,
> Ng Poh Khai
>
__._,_.___
Primary EnergyPlus support is found at:
http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx
The primary EnergyPlus web site is found at:
http://www.energyplus.gov
The group web site is:
http://groups.yahoo.com/group/EnergyPlus_Support/
Attachments are currently allowed but be mindful that not everyone has a high speed connection. Limit attachments to small files.
EnergyPlus Documentation is searchable. Open EPlusMainMenu.pdf under the Documentation link and press the "search" button.
Your email settings: Individual Email|Traditional
Change settings via the Web (Yahoo! ID required)
Change settings via email: Switch delivery to Daily Digest | Switch to Fully Featured
Visit Your Group | Yahoo! Groups Terms of Use | Unsubscribe
Change settings via the Web (Yahoo! ID required)
Change settings via email: Switch delivery to Daily Digest | Switch to Fully Featured
Visit Your Group | Yahoo! Groups Terms of Use | Unsubscribe
__,_._,___