As the world — and its landfills and water treatment plants — get more and more crowded, future houses will have to cut down on their waste. Or they could just repurpose it. For instance, they could use household sludge to feed bioluminescent bacteria to light up a room. It’s so simple! Really!

This bioluminescent lamp is part of Philips’ Microbial Home concept, a self-sufficient closed-loop home that wastes not and wants not. The Bio-lamp is fueled by a methane digester, which itself forms the centerpiece of the kitchen (yes) and breaks down waste into a lovely sludge.