Two 17-year-old Kenyans, Fredrick Njoroge Kariuki and Miron Onsarigo, have been named the Africa Winners of The Earth Prize 2026.
Their solution, called HewaSafi (meaning “clean air” in Swahili), is a low-cost vehicle exhaust system. It captures harmful emissions using filters made from maize, agricultural waste, disposed batteries, coconut shells, and algae.
Fredrick’s personal experience with a serious lung condition (bronchitis) caused by air pollution drove the project. He grew up in Naivasha. Miron is from Kisumu.
According to the World Health Organization, air pollution contributed to an estimated 1.1 million deaths in Africa in 2019.
The HewaSafi prototype costs KES 16,288 ($125). It captures over 90% of particulate matter and reduces toxic CO2 and CO emissions. The system is designed for matatus (shared minibuses) and boda bodas (motorcycle taxis).
The team has already conducted pilot tests with a local matatu association. They plan to work with the Eastleigh Matatu SACCO.
The next phase includes a product family: HewaSafi Lite, HewaSafi Pro, and HewaSafi Mobile.
The Earth Prize is run by The Earth Foundation, a non-profit based in Geneva, Switzerland, founded during the School Strike for Climate in 2019. Each of the seven regional winner teams receives $12,500 to develop their idea. A public vote will crown the Global Winner on 29 May.
