Green Wall

If you can model external shading with a varying degree of transparency on a schedule (assuming deciduous plants) then you can simulate that benefit. I am not aware of modeling software that could account for the cooling effect from evapotranspiration of the plants however.

Perhaps I need to understand what you mean by a green wall. I am envisioning a cable system with vines growing on them. We are eQUEST users as well and have modeled that type of green wall as I described. You can account for the shading effect. The type of green wall I am thinking of or the alternative which is more densely planted really has no resistance to conductive energy loss. Same with a green roof - there is no real R-value. So there is no U-value associated with a green wall.

Materials in the model can be assigned a percentage of transparency. For example we attempted to simulate trees surrounding a recent project. We obtained tree heights and images of the surrounding woods. We created rectilinear boxes around the building at the proper distance. We then assigned a degree of transparency to the trees that we scheduled to change seasonally. I think we modeled something like 85% transparency in the winter and 15% in the summer. Not perfect be it should give us an idea of the effect. If you need more specifics let me know.

It is neither a blind or a wall or a window. Create a building shade and position it where the green wall is located. You can then adjust the transparency and change it with a schedule.