Ideas: Waste material as shade structures

I saw an article about cities doing various things to reduce heat, including lighter road surfaces and planting trees. Trees provide good shade and reduce temperatures, and are generally good for the environment, but can require quite a bit of water for dry areas. I got to thinking that we could build artificial tree-like structures to provide shade. But it would require a lot of material, and it would be undesirable cost-wise and environmentally to dig up new materials for this purpose. So I wondered about building them from waste materials.

Plastics have been considered recyclable for a while, but in reality success has been limited here. Separation and contamination have been major problems. China and other countries used to take care of this for the wealthier countries, but stopped. Glass has worked better, but has used a fair amount of energy and had other problems. My city, for one, has stopped taking glass due to the cost. I wonder if such materials that are hard to find a destination for other than a landfill could be purposed to make shade devices.

Perhaps plastic, glass, and/or some other otherwise waste materials could be roughly melted and pressed together to make some sort of shady structure for low cost and low energy. More care would have to be taken forming the exterior to create a more pleasing appearance.

The structure would not necessarily be in a tree shape, but any shape that’s tall and blocks sun, but doesn’t take a lot of ground real estate. It would have to be structurally sound though, especially against wind, so that it wouldn’t fall and damage things or injure people. I saw another article about steam-compressing waste plastic into blocks for buildings, so I’m sure it could be managed.