coreywebster
Well-Known Member
I remember citing that article from the last time we had this conversation. (Or the time before that )In actuality, however, plants do not absorb all incoming sunlight (due to reflection, respiration requirements of photosynthesis and the need for optimal solar radiation levels) and do not convert all harvested energy into biomass, which results in an overall photosynthetic efficiency of 3 to 6% of total solar radiation.
https://en.wikipedia.org/wiki/Photosynthetic_efficiency
Very small amount of light is converted, just consider watts as a measurement of heat since you can directly translate them into joules which can be translated into btu.
Taking into account the first 47% loss from photons in the non bio available range, as with our indoor lights.
That changes the leaf efficiency considerably, once recalculated it could be as high as 22% instead of 3-6%
So giving the differences in LED and HPS spectrum their must be a difference in leaf efficiency between the two light sources.
Albeit a small difference. ? But that would change the amount of light turned into biomass overall.