This is a 'green wall' - at Staffordshire University. There are a number of these around the site.
They are part of a project to see if the plants in them, which are irrigated through small pipes in the trellis, can help reduce pollution in the urban environment. The research is also looking at which plants can do the job best.
I guess the idea is, once that research has been completed, that they will encourage us all to put them up on our houses (etc).
Sounds good to me.