C40 Cities Challenge: Green Umbrellas

Freetown faces rising heat, poor ventilation, and overcrowded public spaces, making daily life uncomfortable for many residents. Our idea introduces a two-part solution: Green Umbrellas and the Cooling Cone. These interventions transform ordinary city spaces into cooler, greener, and more inclusive environments.

The Green Umbrellas reimagine traders’ canopies by covering them with lightweight planters that grow vines and small plants. This simple innovation reduces heat, provides shade, absorbs air pollutants, and brings greenery directly into crowded market streets. Above the busy flow of umbrellas, a continuous green canopy emerges, visually refreshing and environmentally impactful, while also empowering traders with an affordable, climate-smart upgrade.

The Cooling Cone is a public seating and water structure designed to absorb and release cool moisture into the air. Positioned in high-traffic areas, it doubles as a shaded resting point and a passive cooling device. The cone uses water circulation and natural airflow to lower surrounding temperatures, offering comfort to pedestrians while reducing reliance on energy-intensive cooling systems.

This concept aligns with the four green and thriving principles:

1. Complete Neighborhoods – By embedding greenery and cooling into markets and streets, it makes daily life more comfortable without requiring people to travel far for healthier environments.
2. People-centered Public Spaces – The Cooling Cone creates shaded, social resting spots, while green umbrellas improve the aesthetics and comfort of streets where thousands gather.
3. Inclusive Communities – Traders, commuters, and vulnerable groups all benefit, ensuring that climate solutions are accessible to everyone, not just the wealthy.
4. Urban Nature & Climate Resilience – Plants on umbrellas and passive cooling structures increase biodiversity, mitigate heat, and absorb pollutants, contributing directly to Freetown’s resilience.

Expected Impact: This project will reduce urban heat, improve air quality, and enhance daily life in Freetown’s busiest districts. It creates scalable, low-cost models that can be replicated across Sierra Leone and beyond, proving that small, creative interventions can transform cities into healthier, more resilient, and more inclusive places.