Another interesting aspect of growing with LED's is pulsing them. Photosynthesis actually can occur at 100% with LED's being pulsed anywhere from 0-100 nanoseconds, longer pulses than this reduces photosynthetic effect. So by doing this we can save energy as pulsing the LED's for 100us on and 900us off would only have a 10% duty cycle so 1/10th of the total energy would be required compared to constant lighting. https://mywebspace.wisc.edu/tsharkey...ght%201995.pdf
look at the top left corner of page 266 for a detailed graph