You may have heard the terms PPFD, BPFD, and PAR being passed around in your field of awareness as a grower. Some of you have even asked about our own PPFD/BPFD charts for the Electric Sky lights.
That’s what this post is all about!
PAR vs PBAR
What are PAR values?
PAR stands for Photosynthetically Active Radiation.
This is a term used for the light that can be used by the plant for photosynthesis, measured in nanometers: = the space between waves of light. This was the result a study performed in the early 1970s by Dr. Mcree, and found a “range” of 400nm (blue) and 700nm (red). However, this study was not performed using multiple colors of light, as found in nature, but only a single color of light at a time.
Yes, but leaves out Infrared (IR) light which is used in Electric Sky lights.
It is worthy to note that plants use and need a broader spectrum of light to thrive. It would be more accurate to consider the PBAR; Photo-Biologically Active Radiation: a range of light between 300nm (UV) and 800nm (infrared).
The idea of building LED lights that emitted a full PBAR range was the foundation of the Green Sunshine Company!
Notice our Wideband Spectrum below, and how much light energy is created in the 700-800nm range (IR/Infrared) — almost 10%! Using a standard PAR meter would “miss out” on these readings. To capture all of the light output sent by the Electric Sky, we use a special light meter – the Apogee Instruments MQ-610 ePar Meter.
Due to the Emerson Effect, we know that the colors in the IR range enhance growth rates, leaf size, and overall photosynthesis when combined with PAR. So, think Infrared plus anything in the PAR range (blue through red) increases the growth rates when combined together…
What is BPFD/PPFD?
BPFD stands for Biological Photon Flux Density, measuring UV through IR light (300-800nm)
PPFD stands for Photosynthetic Photon Flux Density, measuring Blue through Red light (400-700nm)
These are both ways of saying how many particles of light are reaching a specific point at any given time, measured in micromoles per square meter per second (μmol·m-2·s-1). Photosynthetic photon flux is the variant range (or flux) of the light spectrum where photosynthesis takes place.
We refer to the biological photon flux because plants actually use more of the light spectrum for growth and development. This is why our Electric Sky grow lights emit broadband, full spectrum light.
If you want to dig a little deeper into the science behind this, check out our post on how plants use light!
What does adding Infrared do for Plants?
According to the Emerson Effect (below) when IR/Infrared light is combined with PAR, increases in yield occurs!
Additionally, the following results are continuously reported by our growers and science:
- High Yields due to the Emerson Effect
- Top-to-Bottom Plant Development (Infrared light penetrates beneath the canopy)
- Vigorous Branching — more colas reaching towards the light! (Infrared light promotes branching)
- Faster growth — Many of our growers see 1-2 weeks shaved off of their grow cycle
- Bigger Leaves — Infrared light encourages larger leaves to fill your plant canopy. Bigger leaves means the “solar panels” of the plant soak up more light, leading to more growth
- Flavorful Terpenes — Just like a well-balanced plate of food, if the plant receives a broader spectrum of light, it performs better and creates more terpenes
How do I read the charts below?
The numbers in the charts below are laid out in direct relation to a 5×11 grid we drew out on the bottom of a 2×4 grow tent. We took measurements for our Electric Sky 300 V3 and Electric Sky 180 V3, each at heights of 12″, 18″, 24″, and 36″. Each of the charts are labelled accordingly.
A good thing to keep in mind is the PPFD range of sunlight is between 500 and 2000 μmol·m-2·s-1.
Many of the readings are above 1500, even 2000, which is more intense than sunlight!
This means it’s possible to replicate the intensity of sunlight — indoors! That’s all there is to it…
If you want to start looking more into the science of how plants use light, and how we used our research to develop the first Electric Sky V1 grow lights, you can check out this post!
Now as promised, here are our BPFD charts:
Electric Sky 300 V3 (330W)
Electric Sky 180 V3 (200W)
PDF Workbook (All charts together w/note space)