Solar Analysis is not accounted in Energy Simulation (AC17)

[Anonymous]

It appears that Energy simulation in AC17 INT does not take into account solar analysis that was calculated for any openings in a project.

Test: as soon as you add a window to a south wall (for testing purposes the only window in the project) the Energy simulation ads a "Solar Gain" to "Project Energy Balance" tab, but it does not seem to be taking into account "Solar Analysis" calculated for that window.

Theoretically, (or at least according to the promotional material being distributed), after one calculates "Solar Analysis" for that opening, the "Solar Gain" under "Project Energy Balance" should change if this south-facing window is shaded by model geometry. It does not happen. Even placing a solid wall (properly recognized by Energy Model Simulation) inches in front of the window to completely block the sunlight and recalculating Solar Analysis to properly reflect total lack of solar irradiation makes no difference for "Solar Gain".

To make it clear, "Solar Analysis" works fine. It is the "Solar Gain" under "Project Energy Balance" that does not seem account for "Solar Analysis".

I hope this gets fixed, as this is one of the fundamental concept of solar design.

Thank you.

[Anonymous]

Gabor and Barry,

Thanks for looking this post.
I still used the build 5019, and I will follow Barry's suggestion to update. Thanks!
I will post the result on how it's going.
I saw Gabor's post works just fine on the West side opening.

[Anonymous]

Hi Everyone,

I updated my ArchiCAD 17 INT Edu to build 6004.
My result of the Solar Analysis didn't change.

I share my model here:
https://www.dropbox.com/sh/cxm7wxyxme92jbw/AAC6PW2RAwz2Otav3VirgbDIa

And these are my screen captures of solar analysis:
https://www.dropbox.com/sh/vui50ldfitpmafm/AAAGhN98KOO6MFYqo_hsGbiOa

This is even still happened with new file, new model which start from a scratch.
I'm using the Strusoft Server for climate data.

[Anonymous]

Additional capture:

The radiation on the North Window (and many others) stops at 12 - 1pm.

[Anonymous]

Additional capture:

The sun shines on the North from rises to sets, but the radiation stops at noon.


*Excuse me for multiple posts, the forum didn't let me share multiple images.

[Laszlo Nagy]

Quote from EcoDesigner Star User Manual:

7.5.1 Climate Data Source
Choose an option for the source of the climate data to be used for EcoDesigner STAR.

• Download from StruSoft Climate Server: With this option, climate data are obtained from the StruSoft climate website, at http://climate.vipenergy.se.

All StruSoft climate data are created from NCEP Reanalysis data provided by the NOAA-CIRES Climate Diagnostics Center, Boulder, Colorado, USA, from their website at http://www.cdc.noaa.gov/.

Here comes the important part:

• Use ASHRAE IWEC, TMY, WTEC2 file: Click Browse to select and import data from analytic weather files obtained from an external source (from open source e.g.
http://apps1.eere.energy.gov/buildings/energyplus/cfm/weather_data.cfm or purchased)

Note: Use analytic (“ideal year”) weather data whenever possible, as it usually represents a given location's climate better than climate data recorded in any particular year.

So you should be using analytical weather data (as recommended by Graphisoft) available from various sources (the above link is free, or open-source data) because that is the most accurate. As it seems the data you downloaded from the Strusoft Server is not accurate.

[Gabor Almasi]

Hi,

I could see that the weather data in that location provided by Strusoft is incorrect.
In general we recommend to use open source weather database e. g. http://apps1.eere.energy.gov/buildings/energyplus/weatherdata_about.cfm

[Andy Thomson]

At AC24, with ED (not STAR) this appears to have been completely resolved. One needs an accurate weather data file for sure, we have variously used from the following list:

https://climateatlas.ca/
https://climatedata.ca/download/
http://climate.onebuilding.org/WMO_Region_4_North_and_Central_America/CAN_Canada/index.html
https://climate.weather.gc.ca/prods_servs/engineering_e.html
http://apps1.eere.energy.gov/buildings/energyplus/weatherdata_about.cfm

When we switch on and off a large balcony, and hit 'recalculate' for the solar analysis first and then 'start simulation', we see a difference of solar gains on the order of 500kWh/yr on a single window, and the shading mask appears correctly. However, the analysis must be performed with the 3D view, shading items shown, (or not shown as desired).

[Andy Thomson]

Results from one model featured here. https://www.thomsonarchitecture.ca/2020/08/15/archicad-ecodesigner-and-passive-house/

We have 4 other projects going through EDEE for permit doc submissions just now. Will update the blog when we get further along and have our PHPP review as well.