LED Testing
Below are the results of a grow test between a 400 watt high pressure sodium bulb and our
Procyon 100.  
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Procedure
Test plants were Lactuca sativa var longifolia (Romaine lettuce).  Procyon 100 and HPS bulb were positioned 24" above the plants.  
HPS bulb had a standard textured polished aluminum reflector.  No reflective coatings or materials were used on either grow
chamber.  Temperatures were kept between 70-80 degrees F.  Photoperiod was 14 hours.  Grow media was potting soil with
added perlite.   Additional soil was added around week 2 to help support the plants. Plants were watered every 1-2 days or as
needed.  Gram per watt calculations are based on "bulb" wattages, not "total" wattages (e.g. 400w bulb consumes 430-450w when
the ballast is included)  Grow test was ended early at 35 days due to overcrowding.  (Typical lettuce maturity is 50-70 days)

Observations
Plants under LED lighting grew much quicker than HID, which is most obvious in the first 2 weeks of pictures.  The leaves of the
plants under the Procyon 100 were larger in size comparatively.  The leaves of the plants under the HPS were smaller and thicker.  
Their added thickness could be a defense mechanism against the extra infrared radiation emitted by the HPS, specifically as a
consequence of added waxy epidermal layers to prevent water losses.  This could be a hypothesis for further testing.  

Data/Conclusions
Average weight of HID plants: 51.9 grams
Average weight of LED plants: 52.7 grams

Total power used for HID: 210.7 kilowatt-hours
Total power used for LED: 61.3 kilowatt-hours

Accounting for statistical variations between plants, the Procyon 100 provided approximately the same results as a 400 watt HPS.