Bacterial bioluminescence

Bioluminescent urban lighting uses live biological systems — marine bacteria (Aliivibrio fischeri via Glowee) and plants engineered with fungal bioluminescence genes (Woodlight, Bioo, Light Bio) — to emit a soft, electricity-free blue-green glow for streets, buildings and public spaces, cutting the energy and CO2 footprint of conventional public lighting (worth roughly €2.41 B/year in France alone) at the cost of far lower luminous intensity and the engineering challenges of keeping a living light source alive outdoors.