Is LED more sustainable than HPS? Recent trials in European stadiums gave the answer.
The latest and most scientifically sophisticated test SGL were involved in has just been finished in one of Europe’s most popular stadiums. The results were educational and eye opening and confirming the recent insights of SGL.
For the last 10 years SGL have done extensive research with various light & heat sources and given an objective and thorough view on the technology and developments. This test has once more confirmed that the influence of warmth has often been underestimated as a growth factor. Although light is creating Photosynthesis, the temperature is crucial for the process and should always be in balance with the light. That is the most important difference between LED and HPS lamps, as with HPS up to 50% of the energy reaches the plant as radiation heat, where with LED also 50% of the energy is heat (convection) but it does not reach the plant.
Due to the fact that HPS lamps produce both PAR light and radiation heat, it cannot be controlled separately. The beauty of LED Systems, in combination with IR heaters, is that they have the ability to control light & temperature independent of each other. So in theory, you only apply heat when needed, and light as much as necessary. If you would assume that the lighting systems are used all year round, in many circumstances this could mean LED is more efficient. However, in practise in Europe the main “lighting season” is between September to March. These are the months that the amount of light is not sufficient for (quality) grass growth, but also the outside temperatures are often also not sufficient, so additional heating would be required at all times during these months.