Arctic farming: Town defies icy conditions with hydroponics
hosted.ap.org
hosted.ap.org
Averaged over a day, the sun provides > 12kWh per m^2 in farmable regions (estimated). It takes 70 days to grow cabbage, so for 1m^2 of cabbage that would amount to 168$ at 20cents/kWh.
Indeed. Some harsh places do have lots of essentially free energy, though: 100% of Iceland's electricity comes from a combination of geothermal and hydropower; 99% of Norway's from hydro (source: Wikipedia). I've been wondering for a while if they could use that for this kind of agriculture. Looks like it might work.
In Iceland many greenhouses can grow tomatoes and bananas because they have direct access to hot water from the ground bellow.
But 12kWh/m^2 is for direct sunlight which cabbage etc. probably do not need, as they will have had some thoughts into that, also other hydroponic farms like in Singapore have the same problem. Also the light is tinted more violet and thus more efficiently usable for the plants. And I would not count with 20ct/kWh, as they probably pay industrial rates (though I have no idea how much that is over there).
Also, it's possible to use LEDs tuned to the absorbtion spectra of chlorophyll, as you say.
If my back of the envelope calculations above are wrong by more than an order of magnitude, it might in fact be a commercially viable option for farming.
Is this [1] the Singaporean project you were refering to? They probably don't need heating, but nonetheless their quoted energy needs of 3$/month/structure are astonishingly low.
[1] http://permaculturenews.org/2014/07/25/vertical-farming-sing...
This isn't true. The majority of light from an HPS light is green, yet huge crops are grown using that light all the time. Plants utilize almost every visible wavelength (and some invisible wavelengths) to some extent. LEDs generally just focus on the wavelengths that have been determined to be efficiently utilized. It is all however still 100% crop-dependent. Some plants simply hate LED lighting because of the missing spectrum (like my orchids.)
Except for the lamp, it is just like growing plants in pots outside, except there are 90% less insects and no hungry critters to snack on your crops.
I did some experiments with adjusting the lamp timer and long days didn't keep my beans from producing. Some plants want "seasons" but mine didn't seem to mind.
Now I have a wife, and a basement again, and we are both interested in starting a small "farm." LEDs are viable now and I want to look into this.
I've been looking for a change from outdoor gardening and a high density 1 m^2 indoor plot with 100W red/blue LED + 100W panel + automatic watering system sounds like a fun combination. Plus I can finally try growing tropical fruit and vegetables.
This is interesting - do you have more information on it?
* 45% of sunlight is in the photosynthetically active wavelength range
* Solar cells are 20% efficient
* Red LEDs are 39% efficient and blue LEDs are 35% efficient
So no, I was kind of off base there. Straight sunlight is still 6x more energy for plants. But it is close! 40% efficient panels exist and my LEDs efficiency numbers were from 2012 so the gap might be smaller. If you do this calculation yourself, remember to ignore lumens. They are a human perceptual unit and are completely meaningless for plants.
Now for human-visible light it is a little different. With the most efficient solar cells and white LEDs we can do better than the sun. (Straight sunlight is 93 lumens per watt. A 40% solar cell and 250 lumen/watt LED outperforms the sun.) Maybe this is what I was thinking of.
They must have forgotten about thermodynamics. Even with LED lighting, there's still a fair amount of generated heat to deal with. Also, with LED lighting, you reduce the amount of light actually required for growth as you focus on the more actively-utilized wavelengths of light.
As long as they use the diesel for controlling atmospherics, the rest of the place could easily be done on solar + sufficient battery bank. Arctic and Antarctic insolation is actually much higher than a good portion of the globe. [1]
[1]: https://en.wikipedia.org/wiki/Climate_of_the_Arctic#Solar_ra...
I will add that the article only briefly touches on the lack of roads in Alaska. Alaska has something like six times as many pilots per capita as any other state. Due to the extreme weather during the winter, flying is a common form of travel. This adds to the logistical challenges -- and expense -- involved in trying to import new technologies of this scale.
This is such a wtf.
If wind power was lower in cost, why wouldn't everyone use it over diesel?
It's always a huge warning sign to me.
A project, that looks exciting and new, also powered by renewables.
The meme of funny stories about economics professor wears a bit thin really. Its a harder degree than many people who create these stories have.
If these $20 bills pay off then do it for real not on top of another risky project of picking up a $50 bill for $45
By that reasoning, it makes no sense to install wind power anywhere, because surely in most other cases there were existing power plants, too.
They are stupid people who study at university who reduce brain capacity.
Maybe I'm stupid too but, if wind power worked there then that can be the project, no need to add the agriculture on top of it.Why the hell make it harder and use it on only a untested (For viability) growing machine that might make peoples lives better?
The difference is installing wind power for general purpose use, vs installing it specifically for a single project.
Installing some new power source specially for one project is a red flag, exactly like he says. If it was a good idea it would be installed for general use.
He's saying that installing some new unproven power source at the same time that you are installing some new unproven hydroponics system is a red flag.
You don't do two risky things at the same time when you don't have to.
Much like how solar is super useful on bright hot summer days in the south... It gives the most power when you want the AC on the most
A better example 'might' be plants can take random times of darkness in their stride so random blackouts don't matter. But given the high cost of the setup I doubt you'd want to screw with efficiency.
But probably isn't the word you want when your whole town is dependent on that power source. So you start small, fix the problems that will arise, gain a knowledge base, and THEN move on to bigger things.
Both of these things have changed and large amounts of money have subsequently been invested in renewable energy sources, making them cheaper (mass-produced) and more reliable (better technology).
If you were to re-build the town today, wind farms and battery storage may well be the most economic choice, but to switch to wind, it not only has to be cheaper (and more environmentally friendly) but also so much cheaper that the initial investment costs are returned in a reasonably timeframe.