Green Coal (Hariyo Koila) is a green enterprise currently in the idea phase, aiming to produce eco-friendly coal from human faeces collected from septic tanks. This innovative approach not only tackles the growing issue of river pollution, particularly in rivers like Bishnumati in Kathmandu, but also converts harmful waste into a sustainable energy source. The proposed product, Green Coal, will be tested for its potential to generate sufficient heat—specifically in applications like melting tar for road construction, where traditional methods rely on wood and rubber tires. By replacing these with Green Coal, the enterprise aims to reduce deforestation and chemical pollution, while also promoting proper faecal sludge management. If successful, the idea has strong potential to support both urban sanitation and circular economy goals.