Interesting topics on LED's and diffuse glass
Netherlands: Fairly suprising new results in GreenQ and WUR trials
At WUR it’s becoming clear that beneath Son-T, crops have developed more generative than under hybrid lighting. That, we believe, is due to the higher temperature in the top of the plant and the greater difference in day and night temperature under Son-T. The vine weight (fruit) is also slightly higher beneath Son-T.
Hybrid Exposure
The WUR greenhouses with hybrid lighting showed more evenly-developed crops. That can be contributed to the fact that the LED lamps between the crops emit some heat as well. Production in the hybrid greenhouse under clear glass is about equal to production in the reference Son-T greenhouse.
The difference between the hybrid greenhouse with clear glass and the one with diffused glass is fairly surprising; the diffuse greenhouse has so far produced over a kilo more than the clear greenhouse. In the winter months you wouldn’t expect that, as the natural light tends to be dimmer by itself. Of note is also that in the greenhouse with Son-T, around 10% more energy has been used for heating through the growth tube.
Difference
There is also considerable difference between the two crops under diffuse glass with hybrid illumination at WUR and GreenQ IC. We think that has to do with the fact that at GreenQ IC, virus has been inserted in the crop at the beginning of the cultivation. Propagation at GreenQ IC has therefore been much calmer from the beginning, something that is clearly reflected in the yield. It remains difficult to reach solid conclusions in this case.
A point of consideration is still Botrytis. The plant-affecting fungus has had a comparatively lower impact this year, but even a little is too much. This year we’ll be keeping a sharper eye on irrigation by adding water when the plant evaporates most. That seems to have a positive effect.
All in all it’s a hugely interesting experiment which shows us there’s still a lot to learn.
Source: http://www.energiek2020.nu