A conceptual model for a vertical composting plant
In the north of Munich stand the Highlight Towers — two glass office buildings along the Mittlerer Ring, now facing vacancy.
One highway exit further lies Munich’s composting plant, whose permit expires in 2026.
Our goal: to test and prove that a high-tech biogas and composting facility can exist inside a high-rise.
The concept model visualizes this process.
Project by Elina Tensi & Sonya Fritz — Studio Maciver-Ek Chevroulet
Before the design, we researched DIRT.
What is dirt? Why is something called dirty? What is soil — waste or source of life?
You can find our research here.
The Highlight Towers are a remarkable feat of architecture and engineering. Each tower stands on two steel trusses — no shear walls, only glass.
Dirty?
Inside, bio-waste moves up — soil moves down.
Gravity drives the process. The long open floors allow continuous production lines. Existing ventilation is reused and strengthened — benefiting office space too.
In the taller tower, waste arrives and is lifted to the top by an Archimedean screw.
There it is sorted; metal, plastic, and impurities removed. A bridge connects to the smaller tower, where gravity takes over.
Bacteria in the fermenter create biogas, heat, and liquid fertilizer. The soil drops lower for composting, mixed and aerated in rotating cycles. After three rounds, it’s sieved and ready for pickup at ground level.
Added weight requires new reinforcements, shown in the section.
Ventilation is redesigned: southern tips become solar chimneys pulling hot air up, while cool air enters from the north towers through a water-filled basement. This loop cools the building and improves the office climate.
The double-height fermenting floor creates a spatial openness that remains flexible for future reuse. Its structural system can inspire other floors seeking generous space.
From “dirty” to vital.
From waste to architecture.
From vacancy to renewal.