Tent lighting

200w. Think of it like candle power. 1 candle casts light, 2 candles casts twice the light. 100 candles can light an entire room. etc.. Candle power is the light output of 1 candle cast over 1 square foot of space. The more candles in that SQ, the more intense the light.

Watts stack up and it is 200W "dim setting aside assuming 100%". sound decibels do not stack. if you have two things making 30db of noise your not in a environment of 60db its still 30db till something more noisy comes along. Maybe that's where some of the confusion is from? or maybe the density of the photos emitting from the array? To further this. the 200W boards by spider farmer use to be two 100w boards placed side by side with a fancy connector and more streamlined board. They might both be 100W each but the combined total power they are pulling is 200w. and if you really want to break it down you have 100's of led's pulling 0.25w totalling 200W lol. Scrubbyjimbob makes a good point about the distribution of the light as well. 2x100w boards in 2x4 is fine but 2x100w in a 10x10 is dumb and if they are not stacking or overlapping you are still putting in 200w but its footprint is going to have massive cold spots and be the equivalent of 1x100W under each lamp as they don't connect. Another way of looking at that is by PPFD maps. as long as your hitting a solid number, lets say 800PPFD in 90% of the tent footprint then fuck how many watts it is. its near perfect. after your manage that then figure out its DLI and your balling. Good Luck!

The lights are really only half the equation, you're light footprint matters too. In your question if the two lights are covering the same footprint, then yes it's effectvely 200w-ish but if you spread those 2 100w lights out far enough then it's still only 100w or someplace in-between actually getting to any individual plant.

200 watts, 100 under each board...for a total of two hundred

Those who have 10000W setups, You think have them in one unit or multiple ? Someone needs to go back to school ;)) Or i didn't get the question ;)))