I was thinking about something I use every day as a student, my desk lamp, and how much of an impact that it has every year. In Canada there are about 1 million tertiary students, and if they study a mere hour a day during the school year that's about 11760 giga watts using 60 watt light bulbs for the year.
I thought it would be amazing to use something that doesn't depend on burning coal or produce too much waste, so I thought why not utilize something biological.
I know though that this idea isn't really feasible since it hasn't been developed, and I'm sure that there will be many challenges in developing a bioluminescent light source, and it's definitely not something that's supposed to replace all lighting since the amount of light that these bulbs could produce right now would be only bright enough to light a desk but not a room.
Basically its a glass sphere that has a mesh filling it to provide a framework for the bacteria to grow on. Nutrient broth or another nutrient source is fed through the top every day and feeds the entire bulb with a small tubing system, the bottom allows the few excess drops to come out.
Different solutions could be used, a first one to inoculate the bulb with the bioluminescent bacteria, solutions to feed the bacteria and solutions to clean out the wh*** system; killing all the bacteria and resetting the bulb.