Indoor horticulture provides a controlled environment that protects plants from pests and other external threats. The concept also allows plant growth regardless of the seasons and climate, since any environment can be simulated indoors. However, sustaining the right conditions for indoor growing is energy-intensive.
LED grow lights can achieve significant savings, since indoor horticulture requires a higher lighting output than other commercial applications. Conventional grow lights use fluorescent and HID lamps, and LED lighting allows savings of up to 50%. LED lighting is also a safer option with lower maintenance costs.
The output of a lighting systems is normally measured in lumens, but this is only useful when discussing lighting for humans. When dealing with plants, the concept of photosynthetically active radiation (PAR) is used to describe the lighting output. In simple terms, PAR refers to the amount of light that is useful for plant metabolism.
Direct and Indirect Savings of LED Grow Lights
As mentioned above, LED grow lights can deliver the same lighting output as conventional lamps, while consuming up to 50% less energy. However, the energy savings do not end there. LED lamps also emit less heat, and this reduces the workload on air conditioning systems. Since indoor horticulture has stringent temperature requirements, this is a significant advantage.
LED grow lights also offer maintenance savings, since they last much longer than fluorescent and HID lamps. The typical service life of LED grow lights is 50,000 hours or more, while conventional lamps are normally rated for less than 20,000 hours. This reduces the number of lamp replacements over time.
LED grow lights have a higher price than fluorescent and HID lamps, but their total ownership cost is lower. The energy savings achieved are significant, and their service life is much longer. Professional electrical engineering services are important to ensure that LED grow lights have reliable wiring and electrical protections.
Additional Advantages of LED Grow Lights
That to its reduced heat emission, LED lighting protects heat-sensitive crops. This allows the installation of LED grow lights closer to the plants, allowing a more efficient use of vertical spaces. Real estate costs are reduced when the available floor space is used more efficiently.
LED grow lights are also a safer option, since they can be manufactured without fragile materials. On the other hand, fluorescent and HID bulbs can break with and impact or some electrical fault. These lamps release shards of glass that can contaminate crops, and they also contain mercury. However, both issues are eliminated with LED lighting.
Another advantage of LED lighting is versatility. Consider that the lighting output of fluorescent and HID lamps has a fixed color output, and this is a disadvantage when growing crops indoors:
- The lighting needs for indoor horticulture change depending on the plant. With conventional lamps, different installations are required to grow various crops.
- Even if only one plant species is grown,lighting requirements change during its life cycle. For instance, vegetative growth has different lighting needs than the flowering stage.
LED lamps can be designed with an adjustable color output, which is a significant benefit in indoor growing applications. Instead of requiring a different configuration depending on the crop and its life cycle, the color of LED lights can be adjusted accordingly. Keep in mind that not all LED grow lights have this feature, however, and many are designed with a fixed lighting color.
Michael Tobias, PE, LEED AP, CEM.
Michael Tobias is the founder and principal of Chicago Engineers, an Inc 5000 Fastest Growing Company in America. He leads a team of 30+ mechanical, electrical, plumbing, and fire protection engineers from the company headquarters in New York City; and has led over 1,000 projects in Chicago, New York, New Jersey, Pennsylvania, Connecticut, Florida, Maryland and California, as well as Singapore and Malaysia.