Fingolito
New Member
Hi!
I thought I should share this information as there are many people with questions on whaat types of light and how much wattage to choose from. I have done some research over the last months and come up with a calculation that seems to be great to use as a guide when choosing what type and strength of light to go for!
The idea comes from an article talking about PAR watts rather than watts/lux/lumens. PAR watts refers to the amount of photons available to the plant at a certain distance, this measurement is much better as a guide since it's an objective value and really comes down to the type of light and its efficency in producing PAR (Photosynthetic Active Radiantion).
What Are PAR Watts? - Sunmaster is proud to publish PAR Watt information
As we all know alot of LED manufacturers names their models as for example 400w when it's in fact less and can be very confusing. Just to clear this out before we begin the 400w refers to their estimated OUTPUT wattage and not the INPUT which is what we are interested in. A typical 400w Led usually has a input wattage around 120w.
Now, that being said!
So, the amount of PAR watts we are going to use for this example, and that I would recommend using as a reference not final calculation, is 2.16W per cm2 and is a standard recommended value by manufacturers. What we need to keep in mind is to also make up for the loss of energy into the surroundings, LEDs has a PAR value at 65% efficency whereas most HPS lands between 20-40 so for HPS we will use 35% as a reference mark. This means that only 35% of the energy produced by a HPS is convertible into photosynthesis at a height of 50cm. LEDs on the other hand has a fantastic 65% ratio but as we can imagine the HPS with so much extra power will reach further down the canopy with brute force and that is probably why they are much better in penetration than LEDs.
So take the value 2.16 and add the loss of energy (35% for led) muliplied by the size of your grow space. A 4x4 tent thats 120cm would then require 2.16+35%=2.91. 2.91 multiplied by 120 equals 349.99.
So a LED with a minimum of 350 input watt would then have the recommended light output to cover a 120x120 (4x4) space.
Best is to calculate how much light you are going to need during flower since PAR decreases with height and can be controlled with either moving the light or regulating its watt input value.
Hope this will be of help to anyone with doubts!
Peace!
Sent from my SM-G935F using 420 Magazine Mobile App
I thought I should share this information as there are many people with questions on whaat types of light and how much wattage to choose from. I have done some research over the last months and come up with a calculation that seems to be great to use as a guide when choosing what type and strength of light to go for!
The idea comes from an article talking about PAR watts rather than watts/lux/lumens. PAR watts refers to the amount of photons available to the plant at a certain distance, this measurement is much better as a guide since it's an objective value and really comes down to the type of light and its efficency in producing PAR (Photosynthetic Active Radiantion).
What Are PAR Watts? - Sunmaster is proud to publish PAR Watt information
As we all know alot of LED manufacturers names their models as for example 400w when it's in fact less and can be very confusing. Just to clear this out before we begin the 400w refers to their estimated OUTPUT wattage and not the INPUT which is what we are interested in. A typical 400w Led usually has a input wattage around 120w.
Now, that being said!
So, the amount of PAR watts we are going to use for this example, and that I would recommend using as a reference not final calculation, is 2.16W per cm2 and is a standard recommended value by manufacturers. What we need to keep in mind is to also make up for the loss of energy into the surroundings, LEDs has a PAR value at 65% efficency whereas most HPS lands between 20-40 so for HPS we will use 35% as a reference mark. This means that only 35% of the energy produced by a HPS is convertible into photosynthesis at a height of 50cm. LEDs on the other hand has a fantastic 65% ratio but as we can imagine the HPS with so much extra power will reach further down the canopy with brute force and that is probably why they are much better in penetration than LEDs.
So take the value 2.16 and add the loss of energy (35% for led) muliplied by the size of your grow space. A 4x4 tent thats 120cm would then require 2.16+35%=2.91. 2.91 multiplied by 120 equals 349.99.
So a LED with a minimum of 350 input watt would then have the recommended light output to cover a 120x120 (4x4) space.
Best is to calculate how much light you are going to need during flower since PAR decreases with height and can be controlled with either moving the light or regulating its watt input value.
Hope this will be of help to anyone with doubts!
Peace!
Sent from my SM-G935F using 420 Magazine Mobile App
