Medellin is becoming the most modern green city and architects are certainly designing having in mind bringing back the green to the entire city, and people are ecstatic about it. The more greenery the better, right?
Belgian architect Vincent Callebaut has designed a conceptual transport system that would involve airships powered by seaweed. Called Hydrogenase, the project envisages that by 2030 there could be farms in the ocean producing biofuel from seaweed and acting as hubs for the aircraft. Here's a lot of text from Callebaut: “HYDROGENASE” ALGAE FARM TO RECYCLE