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Light Planning Process: the Kroptek Difference

At Kroptek, our approach is to start with the grower. All our products and light planning services have one purpose: to deliver performance and real value.  

Our team of lighting engineers, horticulturalists and product developers help growers define the best solution and light configuration from spectrum to fixture layout, for whatever grow space geometry, crop needs, and budget. 

One of the main steps in helping growers achieve their goals is the light planning. But where to start? 


Understanding PPE 

Photosynthetic photon efficacy (PPE) is a complex concept often considered essential to measure the lighting efficacy of indoor growing environment. However, having the highest PPE does not mean having the best adapted spectrum for the crops or indoor space. 

“The photosynthetic photon efficacy (PPE) is the photosynthetic photon flux divided by input electric power. The unit is micromoles per second per Watt (μmol.s-1.W-1), or micromoles per Joule (μmol.J-1)” according to Hortidaily.

For example, a spectrum with lots of green & blue would have a lower PPE than a spectrum with high red. This is due to the high efficiency of Red monochromatic LEDs, and the low efficiency of LEDs to convert electricity into green photons. The main reason why white or full spectrum light is perceived as less efficient using this calculation is because it inevitably also includes green; compared to purple lights which are a mix of mostly red and some blue. However, this is not the full picture and is a perfect example of why light efficacy is not the key determinant when choosing the best lights. 


Why light efficacy might not be the best choice 

Plants grow healthily and most efficiently under a balanced light spectrum. When it comes to LED lighting, this type of spectrum is often referred to as full-spectrum LED, which is in contrast to the more conventional narrow-spectrum LED alternative. It is especially crucial to provide well-balanced lighting conditions to plants grown under sole-source LED lighting. LED grow lights with a spectrum optimized for plant growth may not excel in PPE due to the PPE variations among LED elements in different colours.” [source]

Some of our recent grow trials show that purple light does make the plant grow faster but ruins the taste. The market is seeing a gradual but definite shift from narrow lights to white lights for good reason. Kroptek started a decade ago as an R&D project studying the benefits of white light compared to the then narrow-spectrum lights. 

It then becomes more important to choose a light fixture not according to its PPE, but according to its relevance for a specific crop and its growing environment. This is one of the objectives that professional light planning achieves. 


Our approach to light planning  

Kroptek offers a detailed light plan and a customised LED grow light strategy using the industry gold standard simulator. This ensures maximum plant response and quality with high light uniformity. 

How do we do it? With a simple 4-step process: 

  1. We get all the specifications necessary from our clients. That includes the type of growing environment (indoors, glasshouses, polytunnels), its location and dimensions, the height or where the lights can be fitted, and the type of crops. We also focus on the grower’s objectives to make sure our light planning achieves them. Is it to get an early season harvest? To increase yields? To encourage certain morphological or organoleptic properties?
    Our experts can also come on site to collect data and provide support adapted to meet the grower’s requirements.
  2. We then choose the right light fixture for the application, cherry picking from our existing product range or proposing a custom solution if needed.
  3. Once the most suitable light fixture is chosen, our lighting and horticultural experts will advise on the required PPFD (Photosynthetic Photon Flux Density​) for the application. This is done thanks to the expertise we’ve acquired over many years developing and testing our different light spectrums.
  4. Finally, we’ll create a layout in DIALux, a top-of-the-line lighting simulation software. The rendering will be used to help growers install their new LED grow lights to ensure maximum uniformity and performance. 


“We make sure to take into consideration all of our clients’ requirements to offer them a solution that is really adapted to their needs. We also have the capacities to customise any light fixtures; so we’re able to give our clients the very best product, no matter their project”
Antoine Charvin, Kroptek Lighting Engineer.


Interested? Contact us for a free light planning today and get the very best for your crops.