BIM Coordinator Program (INT) April 22, 2024

Find the next step in your career as a Graphisoft Certified BIM Coordinator!

Sustainable design
About EcoDesigner, Energy Evaluation, Life Cycle Assessment, etc.

EcoDesigner and EcoDesigner STAR are unusable for design?

Anonymous
Not applicable
EDIT: As it stands today (May 2014, AC17 build 6004) this issue is still not resolved. It has been over a year.

EcoDesigner STAR does not appear to be AHSRAE compliant and should not be advertised as such.

As it stands today (March 2014, AC17 build 5019), both, standard EcoDesigner and a commercial version of EcoDesigner STAR have a fundamental flaw in a calculation of solar gain causing these add-ons to overestimate needed cooling by a huge margin, basically rendering these programs unusable for sustainable architectural design.

Moreover, this is not a new issue. It goes back for more than a year and started when AC17 was released in summer 2013.

I, personally, made this issue public back in summer 2013, shortly after the initial release of AC17, and brought it to Graphisoft's attention in this thread: Solar Analysis is not accounted in Energy Simulation (AC17).

However the issue is not resolved after 6(!) updates to the main program.


The root of this problem is very simple:

One of widely advertised features of AC17 is a, so called, concept of "model-based shading". The idea behind this concept is that a shaded opening (glass door or window) will not add to the solar gain calculations, thus providing architects with fundamental tool of sustainable architectural design.

In other words, if the window facing the sun in your project is shaded by model geometry (overhangs, adjacent walls or buildings, trees, etc.), EcoDesigner and EcoDesigner STAR are marketed as being able to account for that and subtract appropriate amount from total solar gain calculations. In reality - they do not.

Both, EcoDesigner built into AC17 and an expensive add-on EcoDesigner STAR, fail to calculate this issue properly, subsequently, grossly overestimating needed cooling equipment.

I did see a few threads in this forum asking questions about overinflated energy readings for buildings designed, but it appears people do not realize where these miscalculations come from.

Let me explain.

If you have any windows in your project receiving direct sunlight (How many of us have windows in our projects? All of us?) these windows will always be shown as unshaded no matter how you cover them up with model geometry.

Even a solid wall placed right in front of these windows will not prevent EcoDesigner or EcoDesigner STAR from showing these windows as being constantly exposed to direct sunlight throughout a year.

This basically means that EVERY AC17 project that uses EcoDesigner or EcoDesigner STAR (which is worse, as EcoDesigner STAR is a paid add-on, is expensive to own and supposed to be "Standard Compliant") will give erroneous results.

Interestingly, all windows in question are properly calculated and shown as shaded under EcoDesigner's or EcoDesigner STAR's "solar analysis" dialog accessible from "Openings" tab in "Energy Model Review" dialog box.

Moreover, kWh redings for any window shaded by model geometry is also properly reduced.

However, this reduction in kWh never makes it to the Energy Evaluation Report and every window is assumed to be unshaded there, thus ALWAYS showing exaggerated solar gain for any thermal block with windows oriented toward the sun, even if they are completely shaded by a solid wall built wight on top of them.

I am curious. This issue is around since AC17 came out, but I constantly see published success stories of architectural buildings being designed with AC17 and EcoDesigner and supposedly properly calculated in relation to sustainable design.

I wish I knew how they did it. Am I the only one here with this issue?

It is very easily reproduced and ANY project relying on EcoDesigner and model-based shading will ALWAYS give erroneous results.

Basically, until this issue is fixed, AC17 and EcoDesigner or EcoDesigner STAR are a dead weight in sustainable design.

Thoughts?
19 REPLIES 19
hampden
Booster
Re: EcoDesigner and EcoDesigner STAR are [NO LONGER?] unusable for design[!]

I just wanted to post a follow up on the issue I was having in previous versions and say that PHYSICAL SHADING IS NOW TAKEN INTO ACCOUNT IN THE ENERGY BALANCE REPORT in AC18 6004, though It's important that you understand how to update openings to make sure it makes it's way into the energy balance report (see screen shot below).

Unlike the zones which seem to know when something has changed and warn you that you should need to update the zones, you also have to refresh the solar analysis by recalculating any window which has had a change to it's solar exposure (size, shading, orientation etc), so while it's a bit clunky in terms of interface, it does now work if you change an overhang the solar analysis of model based shading makes it's way into the energy balance report - YAHOOO!

It would be nice if there was a one step refresh everything button for smaller projects, though I would guess as projects get larger having the ability to separately control what is being recalculated could become very important.

See attached screen shot of required step to make sure shading makes its way to the openings solar analysis / energy balance report.

I can't vouch for some of the other more detailed issues others were having since this was a show stopper for me to even start using the tool, but am hopeful that this is a sign of general improvements to the tool.

A shout out to Miklos and his team - thanks for making this happen in AC18! - I'm excited to start using it!

pallsopp42 wrote:
At the risk of repeating myself regarding EcoDesigner calculation issues and errors, have the following items been addressed in any updates to EcoDesigner in ArchiCAD 18?

1) When selecting higher performing window frames, the R value drops (not good)

2) Adding physical shading elements over windows doesn't seem to make any difference to the energy consumption calculations but selecting a "shade type" from a list within EcoDesigner does. If we are building physical models of buildings, EcoDesiger should account for the effect of shading devices located on the building. Otherwise the shading devices, while they do indeed throw shadows, become far less useful and more in line with arbitrary applied "aesthetics" - something we avoid at all costs.

3) Placing trees near a building can bring EcoDesigner Star to its knees as it calculates the shading effect of leaves on the building - yet actual shading devices seem to have no bearing on EcoDesigner's energy assessment

4) Are we ever going to get the range of typical HVAC equipment in used in the US? For example, will EcoDesigner ever link HVAC objects such as ductless split air distribution units or specific heat pumps for ductless interior devices so as to account for the actual power loadings and the actual cooling (or air-heating) efficiency of these systems?

It is CRITICAL to professional credibility to have accurate calculations come out of EcoDesigner and EcoDesigner Star (why have two variants by the way when only one of them does the job?). Thus far as a firm using ArchiCAD 18 and Ecodesigner in the US, our requests seem to have fallen on deaf ears. At least that's how it feels as a firm whose primary focus in using ArchiCAD is to create accurate and complete physical models of structures, and not as a quasi drawing system for supplementing the typical architect's design office processes.

If we knew what the status was of these fixes and where they can be downloaded - e.g. new HotFixes for ArchiCAD 18 - it would let us know how to proceed - use EcoDesigner Star or just return to a completely unlinked, standalone "guestimate" system not connected to the BIM model, the latter of which is very unsatisfactory.

Any light you can shed on these issues would be very much appreciated.

Thanks

Phil
____________________
Phil Allsopp, D.Arch, M.S.(Public Health) RIBA, FRSA

Principal
Transpolis Global: USA, Inc.
W: www.transpolisglobal.com
E: phil_allsopp@transpolisglobal.com
E: pallsopp42@gmail.com

Phil Allsopp, RIBA, FRSA
Principal and Trustee
Smart Pad Living, LLC
E: pallsopp42@gmail.com

Adjunct Professor
ASU Global Institute of Sustainability
E: pallsopp@email.asu.edu

M: 480-276-7707
S: philallsoppskype
T: pallsoppRIBAUSA

ArchiCAD 18
EcoDesigner STAR
MEP
CADIMAGE electrical

OS X (Yosemite Beta + OS X 10.9.4)
iMac (3.4 GHz Intel Core i7; 16GB RAM)

Screen Shot 2014-08-26 at 4.15.33 PM copy.jpg
Stefan Hampden
CAST architecture - Seattle architect
Laszlo Nagy
Community Admin
Community Admin
This is good news.
But one question: are you referring to AC18? Because that is at build 3006 at the moment. However the latest in AC17 is build 6004.
Loving Archicad since 1995 - Find Archicad Tips at x.com/laszlonagy
AMD Ryzen9 5900X CPU, 64 GB RAM 3600 MHz, Nvidia GTX 1060 6GB, 500 GB NVMe SSD
2x28" (2560x1440), Windows 10 PRO ENG, Ac20-Ac27
hampden
Booster
Good catch laszlonagy - you are right I had both 17 and 18 open when I was writing that. I tested it in 17 6004 and it was not working with that version / build - must have looked at the build number for 17 when I was talking about 18 - So to be clear - my comments below were regarding AC 18 build # 3006.

Stefan
laszlonagy wrote:
This is good news.
But one question: are you referring to AC18? Because that is at build 3006 at the moment. However the latest in AC17 is build 6004.
Stefan Hampden
CAST architecture - Seattle architect
Laszlo Nagy
Community Admin
Community Admin
Thanks, that is an important piece of information.
Loving Archicad since 1995 - Find Archicad Tips at x.com/laszlonagy
AMD Ryzen9 5900X CPU, 64 GB RAM 3600 MHz, Nvidia GTX 1060 6GB, 500 GB NVMe SSD
2x28" (2560x1440), Windows 10 PRO ENG, Ac20-Ac27
Anonymous
Not applicable
I set up a LinkedIn group (ArchiCAD + Passive House) where I posted specific questions relative to some of these issues.
A number of Graphisoft folks have kindly joined the group and several have recently visited the dropbox folder where I placed PLN's and other supporting data.
Hoping for a preliminary response from Graphisoft in the near future.
Feel free to join the LinkedIn group. Share your email address with me and I will send you a link to the dropbox folder.
Regards,
David Bitter - AIA, CPHC
SOLERA STUDIOS
(404) 272-7678
Anonymous
Not applicable
Our office has been trying to determine how to use ArchiCAD 18 EcoDesigner Star to produce an energy model for the LEED energy credit and integrate it into our projects at an early phase.

I am looking for help from an EcoDesigner Star user who has fulfilled the LEED energy modeling requirement in compliance with ASHRAE 90.1 appendix G.

I have created an energy model of a large commercial building and was wondering if there is anyone out there who can help troubleshoot through some of the differences between the requirements of ASHRAE 90.1 and the ArchiCAD software inputs.

Below are a few of the areas I am looking for help with.

1. How do I model the parking garage?

2. What are the systems input values for the baseline building, and for the proposed design?

Joseph Cox
jcox@rhodepartners.com
energy report snap.JPG
Miklos Sved
Graphisoft Alumni
Graphisoft Alumni
Hi Joseph,

I really need to know more about your project to give you a detailed answer but here are some generic thoughts that I hope will help you with your work:

1) Naturally ventilated/partially open parking garages should be excluded from the building energy model and only viewed as a shading object. Mechanically ventilated/underground parking garages are modelled as Unconditioned Spaces. With no heating or cooling equipment installed, the internal temperature is allowed to free-float (check whether it remains within the comfort range required for garages throughout the year). Mechanical ventilation system and lighting equipment should be modelled as their energy consumption must be included in the calculations.

2) For baseline system descriptions please reference ASHRAE 90.1 APPENDIX G Section G3
When preparing the energy model of your own design, follow the instructions of Section G3 as well but input the system design parameters proposed by your system engineer.

Best Regards,
Miklos Sved
Graphisoft Product Manager
Anonymous
Not applicable
Miklos wrote:
Naturally ventilated/partially open parking garages should be excluded from the building energy model and only viewed as a shading object. Mechanically ventilated/underground parking garages are modelled as Unconditioned Spaces.
Best Regards,
I agree it should be modelled in specialized CFD-fem Multiphysics software
You need to deliver live links to models and please dont waste time on static IFC conversions HTH
Anonymous
Not applicable
Thank You Miklos Sved and DesignEngineerBIM!
We have returned our license for EcoDesigner Star. Part of the reason was that as architects we do not have the MEP expertise to utilize the software. We are looking to IES for our next projects.
Anonymous
Not applicable
Treebranch wrote:
Thank You Miklos Sved and DesignEngineerBIM!
We have returned our license for EcoDesigner Star. Part of the reason was that as architects we do not have the MEP expertise to utilize the software. We are looking to IES for our next projects.
Pitty, you could have easily simulated the underground carpark air flow and contaminant flow in a fea- multiphysics programs like comsol, ansys, etc.
coupled with stress,strain,thermal,CFD, acoustics,etc..perfect for prelim analysis/presentations

https://plus.google.com/u/2/photos/114544938995916531570/albums/6122128602851164609

Comsol allows engineers/users to develope stand alone apps.

Interesting article here
http://www.engineering.com/PLMERP/ArticleID/9672/Multiphysics-for-the-masses-COMSOL-wants-to-democra...
Learn and get certified!