„By maximizing green content and minimizing red content versus standard lighting LEDs, this LED color enables significant enhancements to luminaire cost and performance.“
I thought plants look green because thats what they reflect? Meaning that the other wavelengths are absorbed for photosynthesis.
Yeah that seems odd to me. Chlorophyll largely doesn't do anything with 500-600nm wavelengths, and that's where this LED outputs a lot of energy. If this was a bulb that could switch between red and green that might be useful for dealing with day/night cycles for plants, but this LED seems like it just outputs more green light than normal?
A graphic on the page notes that these are designed to be used with red 660nm bulbs. A lot of current grow lights are white, blue, and red bulbs. It seems these are aiming to create the blend of blue and white so manufacturers can blend them with red without worrying about the white/blue mix.
>In contrast to the significant effects of blue light, increasing green light in increments from 0 to 30% had a relatively small effect on growth, leaf area and net assimilation at either low or high PPF. Surprisingly, growth of three of the seven species was not reduced by a treatment with 93% green light compared to the broad spectrum treatments.
Seems like green light is not useful for all cases, but I would indeed like to know exactly why that's the case.
There's too much green light in sunlight, so to reduce free radical formation, most plants reflect most green light (something you may have noticed.) Converting light into chemical changes (splitting water, then sugar) without causing a lot of damage from free radicals is not trivial.
A joke on myself, too. I swear our associative minds, knowing that peeps who wear green clothes and buy green cars, like and want more green; decide plants aren't rejecting green light (the obvious physics) but that they must want, love and use green light. An error I made myself until fairly recently.
That, too. But it's also much easier to sell plants that look the right color to people perusing them. Ever see a commercial or resale garden center using fuchsia-tinted grow lights? No? That's because they're out of business.
That's assuming a wholesaler business that ships to retail. There are plenty of us out there who actually let people - even commercial customers - into our greenhouses in person. Until this development by Cree, all of our viable options for LED lighting were huge pains in the posterior (hence I'm still on fluorescent). This is much much simpler, and will definitely accelerate my own switch to LED.
In a way, you might say that until now, LED grow lighting was only feasible on a very very large scale, or a very small scale, and the medium-sized local nurseries and greenhouses were just out of luck. Cree seems to have changed that.
The red content is intended to be supplied by a separate red LED. A red LED produces red much more efficiently than the phosphor on a white LED, so it saves power to leave red out entirely if you know it will be paired with red.
Iirc chlorophyll has 2 very distinct absorption peaks [1] so it should be possible to design lights that target those frequencies. But knowing how LEDs work and the hacks with wavelength adjustment we use with phosphorus and others I’m sure it’s not easy.
Cree acknowledges this in the link, listing "Reduce complicated spectral analysis" as a feature, implying its just an easier way to achieve what is already done with multiple LEDs working together.
I mix 6000K/6500K (daylight) LED strips with 2700K (warm white) ones and plants seem very happy about it and it is OK for humans, too.
In fact I previously used only 6000K LED strips (in an insulated box so no other light at all) on cycad and other seeds and got very healthy plants.
I think the key for commercial applications like vertical farms is to optimise energy use by trying not to waste electricity on wavelengths that won't do much to boost production.
UV Ultraviolet light (UV-A, UV-B, and UV-C,) and near-UV "antimicrobial violet light" are sanitizing radiation.
Natural sunlight sanitizes because the radiation from the sun includes UV-* band radiation that is sufficient to radiate organic cells at this distance.
EM light/radiation intensity decreases as a function of the square of the distance from the light source (though what about superfluidic wave functions and accretion discs and microscopic black hole interiors (every 30km by one estimate) and Lagrangian points,).
> Short-wave ultraviolet light damages DNA and sterilizes surfaces with which it comes into contact. For humans, suntan and sunburn are familiar effects of exposure of the skin to UV light, along with an increased risk of skin cancer. The amount of UV light produced by the Sun means that the Earth would not be able to sustain life on dry land if most of that light were not filtered out by the atmosphere. [2] More energetic, shorter-wavelength "extreme" UV below 121 nm ionizes air so strongly that it is absorbed before it reaches the ground. [3] However, ultraviolet light (specifically, UVB) is also responsible for the formation of vitamin D in most land vertebrates, including humans. [4] The UV spectrum, thus, has effects both beneficial and harmful to life.
> The atmosphere blocks about 77% of the Sun's UV, when the Sun is highest in the sky (at zenith), with absorption increasing at shorter UV wavelengths. At ground level with the sun at zenith, sunlight is 44% visible light, 3% ultraviolet, and the remainder infrared. [23][24] Of the ultraviolet radiation that reaches the Earth's surface, more than 95% is the longer wavelengths of UVA, with the small remainder UVB. Almost no UVC reaches the Earth's surface. [25] The fraction of UVB which remains in UV radiation after passing through the atmosphere is heavily dependent on cloud cover and atmospheric conditions. On "partly cloudy" days, [...]
(Infrared light ~is heat.
There's usually plenty of waste heat from mechanical friction, exothermic chemical processes with gravity, lossy AC-DC conversion, and electronic components that waste energy/electron_field_disturbance//thermions/heat like steaming water towers sans superconducting channels wide enough for electrons to not start tunneling out without a ground or a negative)
Just a layman here but I know plants use color temp as a signaling mechanism (e.g. to help determine time of year - warmer color temp in spring/fall) so I'd expect some variation between species in how that signal is interpreted and used.
They also take advantage of different spectrum/color temp at different points in their lifecycle too. I was growing pre-led era and I'd swap bulbs for the weed growth phase and then flowering phase.
It's really complicated, because plants also use other bands of color for decisionmaking (e.g.: am I being shaded out by another plant? Am I tall enough? What time of year is it? Should I make flowers? etc). Growers and light manufacturers have found that adding some infrared and other frequencies help, even though they don't contribute substantially to energy absorption.
Also, there are multiple chlorophyll molecules, with slightly different spectra. Lots of fun stuff in this field.
when I went to farming school around 1998 - 2000 we once visited a local commercial greenhouse and one thing I remember is they told me they used to have chemicals (plant hormones possibly?) that they sprayed on the leaves of flower plants to stop them from stretching and develop a more compact form, but had stopped doing that and now just lowered the temperature in the room a couple of hours before sunrise to get the same effect.
I bought some grow lights last year. Monios. Lightweight. Hang 4' strip on string. Miracle of economic design. A finely tuned spectrum. Blazing fuchsia. Like aliens are landing. Plants like em.
Anybody in horticulture or botany knows what a BFD this is. Anybody else... it's major.
Those of you wondering about the green spectrum, try running a commercial greenhouse with fuchsia-tinted lighting. You'll have a paradise of lush, happy plants that never go anywhere (i.e. they won't sell).
Because humans are visual creatures, and we like our plant leaves green, and our flowers bright.
Rephrased, just like in cooking, presentation is very important in commercial agriculture and horticulture, too. People hesitate to buy things that don't look like they expect.
Nothing Cree is doing here hasn't been done before in terms of plant growth, but they've made it hella easier to have a horticultural/agricultural LED installation that fits seamlessly into existing business processes with minimal headache.
I think that this will impact interior and home decor as well. Here we want light that will render colors well and be healthy for plants and humans alike. But this was often expensive (thinking of Metal Halide lamps) or compromised on human comfort (thinking of Flourescent grow lamps). Cree has made it more affordable and healthy to bring living plants into human spaces as a general rule. Which is very exciting from a design perspective!
cannabis is fine with purple light. My begonias, however, which are supposed to have a bright multicolored foliage as their main feature, come out looking about as impressive as cabbage under purple lights. with a bit of extra "warm white" light they become colorful again.
"peak efficiency" is fine but the rest of what the plant is doing counts too and those less efficient processes may have benefits in the final product.
But does it matter what they look like in the indoor garden under purple lighting? I mean eventually you take them out and admire them in natural lighting. Unless, of course, you have customers visiting your garden...
it matters when i take them out to sell to people as decorative houseplants. they'll adjust to the light they're in in a matter of weeks anyway, but they need to look their best when being shopped to new homes.
You mean the purple color light physically changes the color of the plant? I didn't know that. I tried googling and can't find examples. Can you provide some evidence? It seems hard to believe.
I suspect the OP means, or at least the way I parsed it, is that they'll adjust to the changes to their lighting conditions, not that the light materially affects their physical coloration.
i.e. when someone buys them, they'll have to adjust to natural (i.e. sun) light, rather than the artificial growth lighting.
If it was true it would be easy to find photographic evidence online. The fact no one in this thread can provide any evidence makes me think this is a rubbish claim.
that's a big assumption, seems like you'd need to find a paper that did an experiment that compared color temps of lights effects on plant leaf color or do some analysis of levels of pigments present in leaves.
A retail greenhouse would tend to use Metal Halide lighting. It has a wide spectrum that covers human and photosynthetic portions of the spectrum, with a light that looks a lot like natural sunlight. But MH lamps are expensive, hard to install, and can cause fires or explode.
If these LEDs let us design LED fixtures that make both humans plants happy while cutting costs vs MH Lamps, then these lamps will gain market wherever we currently use high quality MH lighting on plants. This might let interior designers substitute MH lamps for plants displays in retail, office, or living spaces.
Likewise, broad spectrum light can reduce fatigue and boost the efficacy of visual plant inspections. If the new LEDs cost the same as the purple LEDs, then indoor farmers may choose the new LEDs to make their work more productive.
I recently became enamored with begonias. The four I’ve collected so far spent the summer outside under my patio and look gorgeous!
One plant was purchased online and arrived with pukey, neutral foliage. After a few months outside, it’s this beautiful, deep, iridescent red on a black border. My wife thinks I’m crazy for how much I fawn over them.
Cree, Nichia, Osram, and Samsung were already selling horticulture-optimized white LEDs. What seems to be new here is a choice between three options for blue/green ratio.
Cree is a part supplier to loads of manufacturers of commercial products. You can add Cree as a search term when looking for high quality LED lighting (and you'll get lots of knockoffs depending on where you're looking).
Digi-Key stocks CREE stuff, looks like they even have this product [1]. Obviously you need to roll your own board, or hand solder/wire them but that wouldn’t be too difficult.
I have yet to see a horticultural LED that cannot be bought by regular people. The indoor grow market, especially for cannabis, is humongous. If you can buy them in 10,000 piece lots as a business, they will have no problem offloading them to lower level consumers for a decent markup. Ive made a lot of money myself sticking bare LEDs to chunks of extruded aluminum heatsink and reselling them to growers, and even that makes me feel like im ripping them off because it is so dead simple to do yourself.
Digikey, Mouser, etc, all carry Cree parts. Rapidled.com also carries all the important parts used for DIY grow lamps, and probably will end up carrying them when they get released.
While these might be new to Cree’s offerings, LED grow lights have been widely available for a few years now.
They’re even used in “vertical farms” to grow herbs (other than cannabis) hydroponically indoors, exclusively in artificial light, with very little human intervention:
Pick the sci-fi scenario of choice here, the tech exists and is economically viable, at least for high value crops that place a very high premium on freshness.
They are new to Cree, who is a more mainstream manufacturer.
The growlights that power the vertical farms (which are, let's be honest, mostly weed farms) come from vendors (e.g. Fluence) that are more specialized, and therefore are fairly expensive. About $1500 per 4x4 foot grow area, last prices I saw.
I dunno if this will ever be economically feasible outside of high-value crops. A Spyder rig from Fluence draws about 630W. But yep, it is at least a step forward, and way better than the weird fluorescent/MH/HID options.
My point on the "sci-fi scenarios" was more for crewed exploration and settlement of space in the medium and long term future.
While there are plenty of other reasons to be skeptical about that, the ability to supply them with some fresh food without requiring magic biotechnology is certainly one barrier crossed off the list.
I think you might be confusing lighting fixtures (what fluence makes) vs actual leds (what cree does). I suspect fluence is probably using osram leds for their products.
How is $1500 per 4x4 area possible? My 4x4 tent is somewhat over-lit using brand new Samsung LEDs with a dimmable, low-heat, high-efficiency fixture and it cost me more like $800 CAD. What do these lights do that mine doesn't?
The actual power draw on mine is about 460W according to a kill-a-watt, which seems like plenty for a 4x4 space using high quality LEDs. 630W seems like far too much, but I'm also a relatively clueless hobbyist. This light certainly grows lettuce and herbs really well, but maybe it would be terrible for tomatoes/cucumbers/peppers.
has anyone compared energy using LED used in growing plants? sure sun is free but in winter conditions or at night for example? would it be more cost effective to keep plants in the sun during the day and give artificial light at night so that they keep growing 24x7?
Most plants need a dark period in order to grow well. You don't actually want 24x7.
A lot of northerly greenhouses use sun + supplemental lighting to keep the day length long for maximum growth, however, while not paying to keep the lights on all day.
The fixtures are sold as a for-product solution. They are set up to have flex connectors so the plants can be put on movable racks (with multiple levels) and share power supplies. They are definitely not a hobbyist thing. Think of them as the Cisco switches for growing dope.
There's also some woo-woo about specifically tuned frequencies. This may or may not be a Real Thing, that's not in my wheelhouse.
>630W
They have multiple watt ranges. Another set is more like 340W. The 630W is more for the flowering stage.
I have never grown or used weed at all, but I have done the electrical design work for a largish facility. It's all really fascinating, but it is also a niche market that has a lot of "dude, weed" guys at all levels.
The new development here seems to be that these are white LEDs that can be specced in terms of blue/green ratio, rather than metrics based around human vision (color temperature, tint, and color rendering index).
Cree and other manufacturers have been offering horticulture-specific LEDs for some time, both red/blue and red/blue-weighted white like these. Here are some of their competitors:
Benefits of white is it looks more natural for people buying/inspecting plants, think aquariums etc. Benefits of narrower band LEDs is it’s more energy efficient and cheaper, think indoor lettuce / pot farms.
I tried using these lights when I moved my plants into the garage one winter. The light from the blue/red is so harsh on the eyes. I totally hated it. I get the zero energy wasted on the light the plants don't need/don't use, but after that I assume that the savings from using LEDs was way more than the old full spectrum hot lamps so emitting more human friendly light is well worth it to me.
In my greenhouse I use half white, half blue/red lights. The resulting colour is not uncomfortable, and I can just turn off the blue/red lights when I want to inspect the plants in white light.
To be honest though, I have no idea whether it saves a noticeable amount of energy compared to using just white lights.
> I'd love to find out how they managed to stay on top.
Me too.
"In May 2019, [Cree] sold its Lighting Products division to Ideal Industries... In March 2021, the company sold its LED Business to SMART Global Holdings for up to $300 million... In October 2021, the company changed its name to Wolfspeed."[1]
I'm pretty confused by this announcement. How is "Cree" doing anything, when their name changed to Wolfspeed and they no longer have a lighting products or LED business? What gives?
I grant you, it is a confusing time line, but let me clear this up. Cree sold its consumer lighting products business (think LED light bulbs with "Cree" stamped on them) to Ideal Industries. Then, as the company expanded into other semiconductor areas, they rebranded as Wolfspeed. Finally, Wolfspeed sold the LED components division (think tiny LED chips that go into products) to SGH, effectively spinning it off as a new company called "Cree-LED".
How in god's name do you obtain this kind of intel? Putting together these kinds of corporate merger/acquisition narratives is always a major pain for me!
I think it is a pretty cool fact that because of the ability to use LED lights in this manner where they emit only the ranges of light wavelengths that are beneficial to plants, you can actually capture sunlight with solar panels. Convert that light to electricity. Then re-emit that electricity as light through these narrow range LEDs as well as store it and emit it over longer periods of time. You actually end up with more plant growth than would be possible if the plants were directly in the sun.
The bit about plants benefitting more from intensity is, as far as I understand it, false - plants are only sensitive to light in fairly narrow wavelengths, which is why grow lights aren't necessarily white. (Source: partner is a professional horticulturist who sourced grow lights for the botanic gardens he works at)
However, GP may be right about the conversion efficiency destroying any gains that you might get from re-emitting light in only those wavelengths. The energy conversion efficiency of even the most efficient LEDs seems to only be about 50%, with the rest emitted as heat. (Source: just a quick Google, so take with a grain of salt) And then you've got the solar panel efficiency on top of that, plus any necessary voltage conversion. Definitely quite a tough ask.
I don't think you are correct here. It may vary by plant species, but plants grown under grow lights in the correct spectrum grow significantly faster than a control plant in direct sunlight.
Talking out aloud here...could vertical farming help here? My theory is that we only use so much land because it needs access to the sun. If we use LED's and stack vertically, we can condense down the footprint.
>That is cereal crop agriculture, which can't be done in vertical farms anyways.
Then why even bother? Just go straight for artificial starch synthesis then. The saved land can be used to produce everything else on agricultural land.
It sounds ridiculous that people are proposing to basically build an VR arcade for plants.
> You actually end up with more plant growth than would be possible if the plants were directly in the sun.
More plant growth and less loss to pests. But the sun is free and agricultural land is cheap, so I know of few plants (other than the obvious one) that are economical to grow this way.
>The “farm” produces four harvests per year. With every harvest, enough wheat is grown to make one loaf of bread (580 grams), which has a cost of at least 345 euros.
>Calculated at a yield of 175 kilowatt-hours per square meter of solar panel per year, the indoor cultivation of 1 m2 of wheat requires 20 m2 of solar panels.
I don't think wheat is a good candidate. But also, that article is about an art installation and it doesn't appear to be using narrow band light emission as the light color directly over the plants looks rather natural.
Im surprised by the number of people here that didn't know Cree has been making horticultural lights for years or know that there are multiple other companies making high performance horticultural lights for many years. I was building grow panels and lighting setups for cannabis years ago to get people off from using shitty blurple LEDS or shitty sodium bulbs or florescent bulbs and whatever other super inefficient garbage that people have been buying.
I find it incredibly sad so many companies are scamming people selling 20+ year old lighting tech for plant growth. Oh sure they save 20% on initial setup costs, only to pay multiple times more than that "savings" in energy costs the first year alone.
Cree hasn't sold one tuned just for agriculture. Instead, people have been using two specific CRI90 variants of the CXB3590, which are quite generic (but the highest PPF/watt on the market until these new ones).
I don't actually know anyone who bothers growing cannabis with their setups. I see it online, but mostly I see people who just like growing flowers, herbs, cucumbers, lettuce, etc.
At the industrial scale I know cannabis is a significant driver of light sales, but I suspect growing food is a huge driver as well.
LED growlights have been commonly available for years. I was using them a decade ago for horticulture. I don't see how an LED company could even NOT be making them. The cannabis industry alone is huge. Seems like Cree is very behind the 8ball in this space if they are just now entering the market.
Question for anyone. I tried researching grow lights and I found mixed information regarding UV emissions. It seemed like maybe some or all grow lights emit UV based on some sources, and then other sources don't mention it at all.
Ideally, it would be nice to have a grow light that doesn't emit UV so I don't have to worry about eye protection and could have the light in common spaces. This is just for 'normal' house plants during winter, not for growing anything for consumption.
After over a decade of me griping at them to get it done.
They're late to the game and adjusted color range and adjustable color temp lighting has been done for over half a decade.
And Cree doesnt even manufacture their own stuff. You cant guarantee quality control, as I recently learned with their XHP35 series. Different color temps come from different manufacturers and the difference in quality of the top cover is drastic. One set, just touching the top cover causes the silicone to shear away, the other, you can rub and bump, nothing happens to the silicone.
Finally. People have been using Cree CXB3590 3000k CRI90 for flowering, 5000k CRI90 for veg for top tier grow rigs for a while now, nice for Cree to recognize that.
Also, they quote "up to 3.25 PPF/watt", which is kind of unheard of. That'd make it the most efficient product on the market by a rather large margin. The highest commercially produced finished products are only hitting between 2.75 and 3.0. Presumably, they're not taking into account efficiency loss from the power supply itself (which would put it closer to 3.0 in reality given your typical Meanwell HLG series PSU that virtually everyone uses).
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