Micromol (μmol/s), PPF and PPFD
Micromol
μMol/s (micromol) is the unit in which P.A.R. is expressed. This unit indicates how many micromoles per second a light source emits. μMol/s is one millionth of a mol (10−6 mol).
Photosynthetic Photon Flux (PPF)
This is related to PPF, which stands for Photosynthetic Photon Flux. PPF measures the total amount of PAR produced by a light source per second. PPF is also expressed in the unit μmol/s (micromol).
Photosynthetic Photon Flux Density (PPFD)
PPFD stands for Photosynthetic Photon Flux Density, which refers to how much PAR reaches the crop. The closer the light source is to the crop, the higher the PPFD will be. The distance from the light source to the crop determines: uniformity, light intensity, and light pollution. The best setup varies depending on the situation and is customized. We are happy to assist you in creating a suitable plan. PPFD is expressed in the unit μmol/s (micromol).
Example Case with
Willem buys a lamp with an output of 2000 PPF. This means that Willem’s lamp emits 2000 μmol/s (micromol per second). The distance from the lamp to the crop is 3 meters. Using a light sensor, Willem can measure his PPFD. He measures that 100 μmol/s (micromol per second) is reaching his crop.
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