Chapter 1 Flashcards
One of the biggest factors limiting the market potential for LED grow lights until recently was the availability of LED emitters that produce the _______________of light needed for needed for photosynthesis, particularly__________________.
Correct spectra
660- nanometer (nm) emitters
______________measure the energy in light and describe how big (how small, actually) the _____________________is at various points along the light spectrum.
Nanometers
Wavelength of Light
The 660nm emitter emits light in the far end of the _____________and is particularly important for _________________
Red Spectrum
Photosynthesis
Newer LED lights offer significantly improved ____________and output ______________compared to earlier generations.
Spectrum
Strength
A second, huge area of improvement is the “_________________” being paired with LED emitters. These small plastic __________________ are positioned atop LED emitters to intensify the light and direct it downward and outward.
Secondary Optics
Focusing Lenses
Secondary optic lenses significantly improve the ________________of the light over the plants’ canopy and _________________ deep into the plants.
Evenness
Penetration
Fact: A ________________high-intensity discharge (HID) light running a 12-hour bloom cycle every day uses 4.3 megawatts of electricity in a year.
At SCE’s current peak rate of $ 0.36 per kilowatt-hour, it costs more than $ 1,500 per year to run one 1000-watt grow light,
1000 watt
Name 3 types of HID grow lights
high-pressure sodium (HPS)
metal halide (MH)
ceramic metal halide (CMH)
In this book, high-pressure sodium (HPS), metal halide (MH), and ceramic metal halide (CMH) are referred to as ____________________.They are similar and often don’t need to be distinguished from each other. All of them create unnecessary ____________and deliver a _______________manufacturer-determined light spectrum.
HID grow lights or HIDs
Heat
Single
HIDs produce lots of ______________ which are ____________________________________that can easily penetrate deep into a garden’s canopy.
Photons
A single packet of light energy at a specific wavelength
A 1000-watt HPS lamp is only about _______________efficient when it comes to growing plants: it produces approximately 400 watts of _______________________________ between 400nm and 700nm, plus 600 watts of “heat” energy above 700nm.
40%
Photosynthetically active radiation (PAR) between
A 1000-watt HPS lamp is only about 40% efficient when it comes to growing plants: it produces approximately ____________watts of “photosynthetically active radiation” (PAR) between ________nm and _______nm, plus ________watts of “heat” energy above ___________nm.
400 watts, 400nm and 700 nm
600 watts, 700nm
This heat comes from the method used to create the _____________.
HID lamps superheat a mixture of _________________until they glow.
Light
Mineral salts
The manufacturing process for LED emitters is expensive, and it produces a wide range of emitter quality levels from batch to batch. Like early computer chips, only a small number of LED emitters produced using current processes are top quality.
The manufacturing process for LED emitters is expensive, and it produces a wide range of emitter quality levels from batch to batch. Like early computer chips, only a small number of LED emitters produced using current processes are top quality.