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New ways to make vertical farming stack up
- dx7tnt 7y agoLink for those without the Economist: https://www.intelligentgrowthsolutions.com/the-economist-growing-higher-new-ways-to-make-vertical-farming-stack-up/ https://www.intelligentgrowthsolutions.com/the-economist-gro...
- sxp 7y ago>The biggest drawback of vertical farming is the high cost of the electricity required to run the large number of LEDS...One way of saving electricity is to use LED s that generate only the colours that plants require, instead of the full spectrum of plain white light. This is a big issue and I've been unable to get good data on it. Opponents of vertical farms say that the high electrical consumption doesn't justify the reduction in energy related to travel. Proponents say that it's possible to optimize LEDs and have continuous fake "seasons" which justify the cost of transportation & refrigeration for certain species of food. Does anyone have any good references that go into the details and provides numbers? Most of the pro-vertical farming information I've found is from companies who are investing in it so they consider the energy numbers to be a trade secret. But there must be some research group or open source team willing to publish all their data so that people can draw their own independent conclusions.
- nkingsy 7y agoNot sure what numbers you’re looking for. Lettuce with state of the art horticultural leds probably can be grown optimally with as little as 10 watts per square foot. Flowering plants need much more and more full spectrum.
- kragen 7y agoIn non-medieval units, that's 110 W/m², 9 times less than direct sunlight. Couldn't you get those low-light conditions more cheaply by stacking lettuce trays in a sunlit greenhouse, with lightpipes to shade the upper levels and get the requisite amount of weak illumination to the lower levels? (Edited to correct the calculated values.)
- TaylorAlexander 7y ago10 W/sq ft is 107 W/sq m.
- kragen 7y agoThank you for the correction! My calculation error (I had written "11 W/m², 90 times less than direct sunlight"), though unintentional, is an excellent demonstration of why using medieval units is a bad idea.
- Dylan16807 7y agoBeing off by a factor of ten is very easy with SI units too. Centimeters vs. millimeters for example.
- kragen 7y agoYeah, and I've certainly made that mistake more than once. (I try to avoid using centimeters or centi-anything for that reason, as well as deci-, deka-, and hecto-.) In this case, though, the calculation I biffed was a unit conversion from medieval units to modern units. It's harder to get calculations wrong when you don't have to do them at all.
- rini17 7y agoWeather would then affect the production, making schedules unpredictable. Plus, I am no expert but I guess you can't make plants actually use much more than 100W/m2 for photosynthesis, the rest of sunlight consists of unsuitable wavelengths. It ends up as waste heat that you'd have to cool away. Perhaps if you could efficiently convert green and infrared parts of sunlight to red/blue, that could help.
- kragen 7y agoYou mean because sometimes it's cloudy? Couldn't you solve that problem by turning on LEDs just when it's cloudy? Plants are pretty inefficient, it's true, but I don't think they're very efficient even with optimal wavelengths. But, yes, solar cells and LEDs can indeed convert green and infrared sunlight to red and blue, with about 3% efficiency under normal circumstances.
- bjelkeman-again 7y agoThat seems about right, based on our lighting plan for our pilot plant.
- deleted 7y ago[deleted]
- bjelkeman-again 7y agoThere isn’t much to be secret about really. When you ask any of the big LED suppliers, like Philips or Hortilux, for a quotation, they ask what you are planning to grow and they give you a lighting plan. The energy usage is relatively predictable, if you know how the building you are in is insulated and you know your ventilation requirements. It isn’t trivial, but it is possible to do the numbers. We will be publishing some data from our pilot installation next year (approx 250 m2 building, 100 m2 active growing area, 30 m3 water). It isn’t a vertical installation, but a Deep Water Culture (DWC) aquaponics installation. We are in the final stages of building it right now. Spent all day working on the decking around the fish tanks.
- cagenut 7y agoanything you share will be much appreciated.
- bjelkeman-again 7y agoIt will be shared over here (not much content yet and ugly, but release early etc.) Translations to come. http://cirkularodling.se/ http://cirkularodling.se/
- Razengan 7y agoOn a tangent, I gotta say I love HackerNews for getting to hear from people working on such projects.
- wallflower 7y agoOn a tangent, in case you missed this https://medium.com/invironment/an-army-of-ocean-farmers-on-the-frontlines-of-the-blue-green-economic-revolution-d5ae171285a3 https://medium.com/invironment/an-army-of-ocean-farmers-on-t...
- ajuc 7y agoI heard about a startup that does specialized artificial lighting for farmers: http://plantalux.pl/en/home/ http://plantalux.pl/en/home/ They have some data http://plantalux.pl/en/plantalux-ex300w-en/ http://plantalux.pl/en/plantalux-ex300w-en/
- lpasselin 7y agoYou might be interested in user superangryguy on Reddit. He experiments with led and has detailed information on LED and plants. He has a patent for growing smaller plants, by lighting with blue light on the stem.
- kragen 7y agodx7tnt responded with a most informative link: https://news.ycombinator.com/item?id=20905033 https://news.ycombinator.com/item?id=20905033 The “food miles” thing is insignificant nonsense; see notes/strawberry-miles.html in http://canonical.org/~kragen/dercuano-20190831.tar.gz http://canonical.org/~kragen/dercuano-20190831.tar.gz. I'm dubious about the economics of the thing. Let’s assume that the power source is solar. The 84% energy loss of solar panels, followed by the 80% energy loss of LED lighting, works out to about 3% of the sunlight harvested getting to the plants. That's a high price to pay for wavelength-shifting and time-shifting; it's hard to see when this would be a better solution than skylights, lightpipes, and colored filters, maybe supplemented by LEDs or low-pressure sodium at night. (Except, I suppose, to avoid violent reprisals for cultivation somebody doesn't like.) If the power source is fossil fuels or nuclear energy, it makes even less economic sense, except at extreme latitudes like those of northern Scotland or Norway, because those energy sources are even more expensive. In moderate latitudes with adequate civil rights, it would seem that the only reason for indoor cultivation with only or primarily artificial light would be an aesthetic taste for the artificial, like tailfins on 1950s cars or the bright blue LEDs on current shitty consumer electronics.
- kokey 7y agoI think at high latitudes the problem is not the total amount of natural light, but the number of hours it shines in a day. Also, other power sources like wind or hydro could be abundant in areas like this. I don't think these technologies make sense because they are better than having to transport food at longer distances, but for some crops it may be quite nice to have it really freshly available at the doorstep, especially crops that normally comes from quite far.
- Havoc 7y agoDid the sun start charging by kwh now? If not then I doubt this is a commercially competitive strategy. Much like coal vs solar it'll get there eventually but I'm highly skeptical of this working out right now.
- kragen 7y agoI don't think it'll get there eventually, unless I misinterpreted you? See my top-level comment for the reasoning.
- Havoc 7y ago>I don't think it'll get there eventually, unless I misinterpreted you? Controlled farming has advantages on pesticide use, water use, location, automation etc. So to my totally untrained eye...that seems like yes eventually that'll eat into the whole LED isn't free like sun advantage.
- kragen 7y agoSure, but as pointed out both in the article and my comment, you can get those same advantages with a greenhouse, except maybe for "location".
- Havoc 7y agoHonestly the whole...this discussion but also something I said somewhere else is a very irritating style. If you want to tell me something...do so. I have better things to do that dig through your post history to figure out what you reckon you might have referenced that is important in your eyes.
- kragen 7y agoOh, sorry about that! I meant https://news.ycombinator.com/item?id=20905366 https://news.ycombinator.com/item?id=20905366 --- I was writing on my hand computer where copying and pasting links is a pain.
- neonate 7y agohttp://archive.is/YwnHT http://archive.is/YwnHT
- decasteve 7y agoI’m a skeptic but vertical farming in the ocean might have more promise like the 3-D ocean farm project. [0] [0] https://www.bfi.org/ideaindex/projects/2015/greenwave https://www.bfi.org/ideaindex/projects/2015/greenwave
- noetic_techy 7y agoEnergy isn't vertical farmings only issue. The fact that you cannot grow staple crops like wheat, soy, or rice indoors is the major issue. Most of what these farms are best suited to grow can be considered "crunchy water" and not nutritious enough to feed a planet.
- hairytrog 7y agocrunchy water. nice.
- ColanR 7y agoWhat about potatoes? Seems like those are a fairly good staple crop.
- onlyrealcuzzo 7y agoNot sure, but I don't think root vegetables are good for growing indoors. They need a lot of soil depth. I can't imagine it'd be efficient, but not sure...
- kss238 7y agoyou can grow root vegetables (at least some) hydroponically
- jdc 7y agoSomebody should tell these "farmers" about sweet potatoes!
- kragen 7y agoIsn't that precisely the energy issue? Or is there another reason you can't grow those crops indoors, other than your light not being bright enough (because making it bright enough and then air conditioning the hothouse is too expensive)?
- elcritch 7y agoStaple crops like wheat, soy, and rice have been honed to near perfection and largely don’t need or benefit from vertical farming. However, you’re conflating calories with nutrition but they’re not the same. Once basic caloric needs are met, a variety of vegetables become crucial in a healthy diet. American diets are terrible for this. It’s often cheaper or easier to buy highly processed foods based on corn, wheat, and soy than vegetables in the US [1]. What’s needed in the US and many modern countries is precisely what vertical farms are good at growing, fresh leafy greens, peppers, herbs, green beans, etc. Shipping fresh vegetables degrades the available nutrients in these items (up to 30% in three days [2). Even then that crunchy water like lettuce plays a crucial role in keeping gut biotica healthy and balanced. Sure vertical farms won’t replace staple crops anytime soon or ever, but there’s an enormous need (in the US at least) for more fresh vegetables. Crunchy water also tastes pretty good if you know how to cook it. 1: https://www.forbes.com/sites/nancyhuehnergarth/2016/03/14/study-finds-nearly-60-of-calories-in-the-american-diet-are-from-ultra-processed-foods/ https://www.forbes.com/sites/nancyhuehnergarth/2016/03/14/st... 2: https://www.chicagotribune.com/dining/ct-xpm-2013-07-10-chi-most-produce-loses-30-percent-of-nutrients-three-days-after-harvest-20130710-story.html https://www.chicagotribune.com/dining/ct-xpm-2013-07-10-chi-...
- akeck 7y agoCan you do vertical farming with light pipes?
- vf3orfeas 7y agoYeah that's a tricky one. First of all it has been settled that white light is the way to go in order to enhance taste and other characteristics. The game is in making led more efficient and plant factories or vertical farms more automated. It also has to do with location, check Japan and China. What you are looking for is research from luuk graamans. He has made some slight errors on the light intensity needed but still. In any case vertical farming now is not there yet in Europe and the US but it will get there. We also did some research on photovoltaic use with some good results :/
- aaron695 7y ago> Each of the nine-metre-high towers Anyone who's not a child knows the OH&S on this in any developed country is a nightmare. But then they would know all the issues that mean vertical farming doesn't work. BUT if you want to push it forward, work on a cheaper medium. This is where it's at. Looks good, feels good, easy on the back, easy on the hands, easy to use AND really cheap. All these attributes are done but not all together, there's no reason they all can't be done together. LED's, designs, plant breeds, electronics are all going full speed ahead. This is where it's stagnating... medium.
- natmaka 7y agoIs it possible to use fiber optics, conducting the light (and UVs, maybe even screening out unwanted ones) obtained from some dome-shaped collectors installed outside (probably on the roof) to the culture? https://en.wikipedia.org/wiki/Light_tube https://en.wikipedia.org/wiki/Light_tube