Recently, we received a great question about lighting efficiency: “I use 1000 watt grow lights, but yours run at 1300 watts.How is that more efficient?” It’s a great question! How can a lamp that runs at 1300W be more efficient than one that runs at 1000W? At face value the numbers seem to tell it all- we’re used to thinking that lower wattage equates to efficiency. However, wattage numbers alone do not tell the whole story- the quality of the light also needs to be taken into consideration. Plants in particular need quality light and lots of it! But what does “quality light” look like exactly? The highest quality light has: The right spectrum How much of the light emitted falls within the PAR range (between 400 to 700 nanometers)? The PAR range is the light plants use for photosynthesis. Lamps that emit a high percentage of PAR light in ratios that mimic natural sunlight are more efficient, since more of it can be used by your plants to grow and thrive. This coupled with the sun’s full spectrum and some tweaking of specific colors can increase yields by more than 30% and the quality of the compounds within the plant by 3 to 5%. High flux density How many photons within PAR is the light actually producing, and how dense is the flow? Think of a high flux density as a tropical rainstorm of light, as opposed to a trickle. (When taking this measurement, consider the height distance between the lights and the plant, and take an average across the canopy to ensure consistent coverage.) Low heat output What kind of heat is coming off the lights? HID lamps put out 50% light and 50% heat, and LED’s generally put out 15% light and 85% heat, driving up cooling loads for air conditioning and ventilation equipment. The heat also means the lights need to sit farther away, which exponentially reduces the amount of light hitting the plants. As you can see, efficiency is not just about wattage. It is about how well a lighting system transforms electricity into value for your plants, the patients, and the growers. Our plasma system converts 75% of the electricity it uses into pure sunlight. It does this so well and so uniformly that two 1300W lamps can cover a 225 sq. ft. area evenly. You would need at least fifteen HID lamps (each 1000W) to cover the same space! I thought this was an interesting way to discuss energy efficiency when it comes to lighting. How efficient are the systems you're using?