Daily Light Integral or DLI is the amount of photons that is received on a square meter for 24h. Plants convert those photons into chemical energy that is stored in carbohydrates and synthetize it with water and CO2. In other words DLI is the breakfast, the lunch and the dinner for plants. The DLI is measured in mol per day or million micromols per 24 hours.
As with all species, no plants are the same and different varieties require different amount of energy levels to thrive. For example, based on the extent research of Purdue University in the United States, to achieve high quality production from tomato and capsicum plants you will need to get at least 22 mol/d, whicle lettuce and common leafy greens would require 13-15mol/d.
Besides, plants cannot absorb unlimited amount of energy. The point after which blasting energy onto the plants is causing stress, is called light saturation point. LIght saturation point is a tricky measurement due to the fact that it also depends on CO2 and water intake.
With the information above, indoor growers can decide fairly easy how long the lights they are installing in their facility should be on. For example, 10 pieces of Flextech Gen 2 growing module are installed at 40cm distance to canopy, above a table of 1.2m by 2.4m. The master grower is using photon measuring instrument and see that the canopy receives 250 mmol/s/m2. The product being grown is boston type lettuce. This means that if the lights are turned on for 12h, the grower should expect to receive 10.8mol/d (250x60sec x 60min x 12h divided by 1 000 000)
For personalized lighting simulation and plan, please contact Flextech Sales Team. sales@flextch.com