LED tube lights on the OPCOM Farm Hydroponic GrowWall.
Food is a critical resource and a lot of work is involved in making sure supplies are resilient and secure. Adding local food production to a community through indoor agriculture can add an extra layer of protection to securing these resources. There are vacant warehouses and other buildings in many cities and towns that can be transformed into produce hubs through the addition of indoor agriculture technologies such as hydroponics and aeroponics. However, when taking these technologies indoors, one necessary component to plant growth must be addressed, and that is light. Plants need light to perform photosynthesis, which is the chemical process by which plants convert sunlight into energy for food. According to a publication from the NASA Technology Transfer Program, photosynthesis is the most important light-driven organic process on Earth.
Sunlight is composed of the full spectrum of light plants need to grow which includes infrared light, the visible colors of the rainbow (known as visible light), and ultraviolet light. Traditionally, providing this spectrum of light to grow plants indoors has consumed vast amounts of electricity. However, this consumption has reduced dramatically as advancements in the light-emitting diode (LED) have made it possible to grow produce using significantly less electricity in virtually any indoor environment. According to a report from the U.S. Department of Energy, the United States used 5.9 terawatt-hours (5.9 trillion watt-hours) of electricity for indoor agriculture lighting in 2017. The vast majority of that power was consumed by supplemental lighting in greenhouses. They also reported that if indoor growers used only LED lighting, there would be a 40% reduction in electricity usage for indoor agriculture throughout the United States. LED technology also brings additional benefits as it produces less heat, is considerably more durable, and can be configured to specific light spectrums and intensities. This method of light production has raised the bar for many indoor agriculture applications, providing another key to new, sustainable techniques and scientific discovery in indoor farming.
A light-emitting diode is a chip of semiconductor that produces light when electricity is added. The semiconductor material of the LED determines how much energy will be released as light and the color of the light that will be emitted. Some LEDs have been commercially available since 1962, but the ability to produce the full spectrum of light plants need did not occur until 1993. That was when the blue LED was invented and it became possible to produce white LEDs through the addition of a fluorescent material. The fluorescent material emitted additional spectrums of light, that when combined with the blue light, created white light. This led to full spectrum LED technologies that can simulate sunlight, making the LED well-suited for plants to perform photosynthesis. In the last decade, this technology has become more economically available and is viewed as a promising source of plant lighting for the indoor farmers of the future.
When a technology emerges, the things that make it impacting are the applications in which it can be used. Innovative ways to incorporate LED technologies for indoor agriculture include the use of solar electricity for zero energy food production. Solar panels convert sunlight into electricity that can be used to power LED lighting, which can then provide artificial sunlight to growing plants. This would essentially be an unconventional pathway for real sunlight to be converted into artificial sunlight for indoor plant growth. Looking beyond indoor agriculture on Earth, there are many that view new plant growing technologies, such as LED lighting, as essential to human space travel. NASA has and still remains "interested in technology for growing plants on long-duration space exploration missions, not just as a food source, but also to perform all the roles they carry out on Earth: eliminating carbon dioxide, providing oxygen, purifying water, and processing waste." LED technologies truly contribute to the sustainability of indoor agriculture, providing options that support and strengthen food supplies, increase energy efficiency, and open up new possibilities for how and where we can grow our food.