Indoor farms, especially in Japan, have been using LED lights for a while. Red/blue combos, in the pink/purple range, seem to work best.[1] The big advantage of LED lighting is not the reduced power consumption, but the reduced heat. The lamps can be closer to the plants without cooking them, which means the trays can be stacked closer and the density of the operation goes up. For most non-druggie applications, the plants aren't that tall. So small, distributed lighting units are used, instead of huge ceiling lamps.
Some plants can be overclocked. They do need a light/dark cycle, but it can be shorter than 24 hours. The life cycle of the plant is then sped up.
Indoor farms, especially in Japan, have been using LED lights for a while. Red/blue combos, in the pink/purple range, seem to work best.[1] The big advantage of LED lighting is not the reduced power consumption, but the reduced heat. The lamps can be closer to the plants without cooking them, which means the trays can be stacked closer and the density of the operation goes up. For most non-druggie applications, the plants aren't that tall. So small, distributed lighting units are used, instead of huge ceiling lamps.
Some plants can be overclocked. They do need a light/dark cycle, but it can be shorter than 24 hours. The life cycle of the plant is then sped up.
[1] http://www.economist.com/news/science-and-technology/2160219...