I am a student learning Grasshopper and Honeybee.
For my Thesis Project I am trying to quantify the Thermal Benefits of Green Facades.
Can someone please tell me how to make a Vertical Green Facade on Honeybee, so that I can simulate the cooling load reduction with Green Facade?
Is it possible to measure reduced cooling load by both shading and evapotranspiration?
Looking forward to your responses!
@Jameela ,
This example file show how to add a green roof to you Honeybee energy model:
http://hydrashare.github.io/hydra/viewer?owner=chriswmackey&fork=hydra_2&id=Green_Roof_In_Energy_Model&slide=0&scale=1&offset=0,0
You can use it to get an estimate of the benefits of a vertical green facade but you should read the E+ documentation on the roof vegetation object to understand its limitations since it says that the model isnāt really intended to model vertical facades:
https://bigladdersoftware.com/epx/docs/8-9/input-output-reference/group-surface-construction-elements.html#materialroofvegetation
Hey Chris.
Thanks for the response. I looked at the File you sent me, and I am getting an error when I tried to read the results. Can you please tell me what this error is for?
I am uploading a picture of the error message.
ā1. Solution exception:C:\Git\OS\openstudiocore\src\model\PlanarSurface.cpp@644 : Cannot create a surface with vertices [[0, 0, 0.003], [0, 0, 0], [0.01, 0, 0], [0.01, 0, 0.003]]ā
I also found a study regarding simulations of Green Facades in Energy Plus. A model for Green Facades was created for the study. This is the link of the study:
These are some of the properties for the Green Facade Model that were mentioned in the study:
Is it possible to change the characteristics of the Material Input in EP Construction to modify it for Green Facades? if so, should the values be modified in the Panel connected to the EP Construction or in the Energy Plus Library?
PS: I have watched all your tutorials on Energy Modelling with Honeybee and found them a great way to learn, thanks a lot for the detailed explanations!
I think the subject is far more complex than you think.
Plants cannot be modeled as simple objects. They indeed have influence on hygrothermal confort, but the building it self has influence on the plant behaviour.
Three suggestions to go further:
1 - read āmicroclimate, plants and faunaā writen by stoodjestike and barkman
2 - look for the thesis of Christian Kongsgaard, and his livestock component (on this forum and his personal website).
3 - Let keep in touch. Iām faƧade engineer for ten years now, and this thema is my subject of research as well.
With regards to your error, make sure that your Rhino model is in meters.
Oh yes ofcourse, my mistake.
Thank You!
@FrehelDenis
Thanks for your response!
I am studying Facade Engineering too, and this topic is very interesting for me.
You are right, I do realise the complexity of the subject.
I looked at the Livestock Component that you mentioned. It sure looks like a very useful tool, however I am a beginner with Grasshopper, and havenāt used much of Python. Do you think it would be advisable for me to use this component as a newbie?
I am trying to arrive at an approximate value for my present study, so could you suggest which would be the best way to achieve this goal?
Hey Jameela
How did it go with your project? Did you succeed in simulating both shading and evapotranspiration? We are two students who are trying to do some of the same stuff in our thesis.
/Christian
Iām a little late to the party, especially with 1.0 out on the town, but I made a component today that creates Material:RoofVegetation inputObj that feeds into HB EP construction.
@Jameela incase two years later this would be helpful,
@chrisoettinger my biggest error educing factor is typos and spelling error; incase this helps you in your ventures
I went down the omg but the physics rabbit hole this morning wondering how to explore green roofās when it comes to PHPP inputs.
** edit with the correct component
The component will RED BOX OF STRESSED until the first 4-5 inputs are given data.
GreenRoofGnome_1.ghuser (6.3 KB)
Hi, Iām trying to study the effects of plants on Microclimate Simulation, so Iām very interested in kongsgaardās research. But I couldnāt open kongsgaardās home page link to get ālivestock.ā. I donāt know if itās my network restrictions. If you can give me a new link, I will be grateful!
I am looking for the link too. The one shared on the portal is expired it seems.
@chris
Dear Chris,
Hope you are good
Kindly I have a question! After reading this conv can I understand that we can not do thermal or daylight simulation for green facades?? Not roof
If yes plz can you send any example for a green facade??
Thank you so much for your help or any other help
The latest development version of the LBT Plugin has a component called āHB Vegetation Materialā that can be used to account for the effects of a greenroof in energy or thermal comfort simulation. You can get the latest development version using the LB Versioner component or you could just wait a couple of months until the next stable relase.
Hi Chris,
I was testing out the āHB Vegetation Materialā but had a few issues. The problems I came across were from trying to use it as a ground material rather than roof material so maybe itās just that Iām using it for the wrong puprose but iāll post anyway in case itās useful for others.
First is that if I plug the Vegetation material straight into the Ground Component it comes up with an error because thereās no roughness value (see screenshot 1)
Since the Ground component didnāt work I built the ground zone from faces and assigned the Vegetation material to the Roof of the ground zone but when I run it through energyplus, shading context isnāt recognised (see screenshot 2&3). Iāve checked boundary condition is Outdoor for the roof and tried adding another soil layer underneath (as suggested in this post Surface Outdoor Temperatures - RoofVegetation (Grass) EP construction not affected by context shade? - #2 by chris)
Ah, thatās a bug. Thank you for finding and reporting it. I just pushed a fix and the component works well afterwards:
I donāt see any shade in either of your screenshots. Only a Room. But the vegetation material seems to be well accounted for in the energy and thermal mapping simulations. For example, comparing thermal comfort above an asphalt parking lot and a tree with grass on the ground:
Thatās a modified version of this sample here.
Oops yes when I said shading context I actually meant thermal zone that should provide shade. But anyway, all is working now. Thanks!
Dear Chris,
Thank you for your detailed insights; it is very interesting to learn more about green roofs and facades.
I have a question for you. The new version of HB for Vegetation Materials forgGreen roofs contains only a few parameters. However, in the older version where construction materials for green roofs were added manually contained more entries as shown in the sample file. How could I add more parameters in the HB Vegetation material node?
Thank you so much!
