Midi’s Solar Chimney

The Midi Tower in Brussels and its open surroundings provided a fitting site for this unexpected marriage. The tower's ventilation system is removed and is then transformed using the solar chimney airflow dynamics, revealing the building’s unique and hidden structure. The collectors adapt to the site's urban conditions, creating a network of public spaces. While the scale of such efforts for one tower may be debatable, this project challenges the misunderstood spatial impacts of energy production, often produced outside cities.

Initiated through collective research on the relationship between sun and architecture, the strange yet fascinating invention of the solar chimney became our object of study. Patented multiple times, this low-tech device harnesses convective energy to generate electricity. Although promising, its scale made competing with other methods impractical. However, the solar chimney’s simple principles became the project’s foundation. The Midi Tower’s conventional ventilation system is removed, and its interior is restructured around new updraft ventilation shafts. Its roof is covered with a smaller set of chimneys that extract stale air, doubling as an accessible solarium. A much larger chimney uses the tower as structural support, channeling heated air and generating energy, while acting as a mirador for Brussels south station. The chimney connects to an atrium, creating a triple-height public space where constant heat offers a tropical public greenhouse. Scattered throughout the site, collectors adapt to soil conditions and urban functions. An urban wasteland is transformed into a productive and accessible garden, storing water in terracotta amphorae. A mineral zone is repurposed into a covered public space for the Midi market. A canopy shelters the bus station’s waiting area, with serpentine pipes running through its collector to provide solar-heated water for the tower. Although debatable in terms of its urban impact, the spatial deployment of this large-scale, low-tech production system serves as an opportunity to enhance and redefine the desolated surroundings of the Midi Tower. The whole functions as an intertwined world of techniques and public spaces, fostering intrinsic relationships between the two.