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WWII Bomb Shelter Becomes Hi-Tech Salad Farm
asjk points out a story of how a World War II bomb shelter, situated 33 meters beneath the streets of London, has been turned into a high-tech hydroponic farm. "The growing system uses energy-efficient LEDs instead of sun, no pesticides, needs 70 percent less water than growing plants in open fields, and less energy than a greenhouse." The computer-controlled environment is designed to shorten the growth cycle of plants like coriander and radishes. They're currently only using about a quarter of the gear necessary to fill up the shelter, but they can produce 5,000-20,000 kilograms of food per year, depending on what they raise. Co-founder Steven Dring said, "We've got to utilize the spaces we've got. There's a finite amount of land and we can grow salads and herbs — which start losing flavor and quality as soon as you cut them — in warehouses and rooftops in cities near the people who will eat them. Use the rural land for things like carrots, potatoes and livestock."
The article (or shall I say shameless advertisement) goes out of its way to talk about how much they shower the growing plants with "nutrients," but says not one iota about the nutritional content of the final product and how it compares to organic or conventionally grown produce.
Use the rural land for things like carrots, potatoes and livestock.
Tell that to the real estate developer who wants to build $1B in homes on a flood plain, gives contributions to the politicians to make it happen, and won't be around when rising sea levels wipes out the homes that homeowners will expect taxpayers to pay for.
ls?
ITS PEOPLE!!!!
Someone you trust is one of us.
Ok, main place I started being skeptical was the LEDs vs the SUN. Now, MAYBE its possible that the LEDs are efficient enough that the electricity cost of running them is offset by the decreased water, other energy needs, but....
The sun is a lot of energy and plants convert light to sugar.... they need light, so converting it to something else and back has to be less efficient than letting it shine on them directly. But....
"no pesticides"....no way. None to start maybe but, plant pests will get in and they will require pesticides to remove. Might get your first crop or two pest free, but without pesticides or a complete sanitary cleanout between crops, its not going to last.
"I opened my eyes, and everything went dark again"
Greenhouses are supposed to trap, and therefore produce energy, not to consume it.
Nae king! Nae laird! Nae yurrupiean pressedent! We willna be fooled again!
child: Father, do you ever think that some day our humble shelter will grow lettuce and fresh produce for people who cant use bicycles with any gears on them?
father: how do you mean, my child?
child: Well, i just want to know, do you think some day people can grow organic vegetables here to sell at a little weekend market that also sells expensive soaps, honey, and pita dips to people who ride broken bicycles
father: Jesus god put your mask on child! the germans are attacking with GAS that makes your children MAD!
Good people go to bed earlier.
a World War II bomb shelter, situated 33 meters beneath the streets of London, has been turned into a high-tech hydroponic farm.
"We had very little work to do to get it going, as it has been being used as a high tech hydroponic farm, wink, for decades."
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
For as much as you all claim that metric is so easy, you sure do screw it up a lot.
"5000 to 20000 kilograms" is inefficient and stupid. It should be 5 to 20 megagrams.
But I'm just a US-dwelling everyday user of imperial measurements, so what do I know? Oh, wait, yes, that's right, I know how metric works! And your failure to use it properly belies its lack of usefulness. So quit bitching about imperial measurements.
There is a bomb shelter built under I-5 near Greenlake in Seattle, that was built in the early 60's (ok, fallout shelter). It was touted, I believe, during the 1962 world's fair in Seattle. Here's a King5 video about it: http://www.king5.com/story/new.... It is a circular room with bathrooms under the freeway, with a small entrance. Later, it was used to issue driver's licenses. I got one there myself in the early 70's. Now, it is a grown-over place used as a City of Seattle municipal records storage center for a few years, and then abandoned. A massive cement structure like a bomb shelter doesn't go away, nice they can be reused in peacetime. What could be more peaceful than marijuana :).
A hidden bunker 100 feet underground with great plumbing and electricity, and you're growing FUCKING LETTUCE??
SJW's don't eliminate discrimination. They just expropriate it for themselves.
The intention was to re-use these tunnels after the war as part of an express underground line. Never happened, unfortunately, as the Northern Line could do with more capacity!
So it's a hydroponic farm secured beneath the streets of London and they're growing "salad"...
I wonder if it's the same sort of "salad" that's starting to get legalised in many American states ?
ls?
Olympis sized swimming poo?
ew.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
In addition to "soil" and water, plants need CO2 to grow. Do they have to do anything to make sure that there is enough CO2 for the plants? That far underground with only the occasional worker providing CO2, I would think the plants would quickly convert the available CO2 to O2. Does enough filter in normally or do they actually have to used forced ventilation? Any idea?
Anyone able to add input on that? My information was that HPS was MORE energy efficient than LED if you went with the correct bulb and wattage... that is... bigger bulbs with the opposing leads.
I'm not an expert but that was my understanding. Naturally the HPS lights can't be near the plants. You ahve to back up. But they cover a much wider surface area.
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
It's pretty hard to get good numbers on this from manufacturers, because almost everyone gives specs in human vision units (lumens, lux, foot candles, etc) if they give any information at all. For growing plants, photosynthetically active radiation (PAR) units are required to make sensible comparison. PAR consists of wavelengths between 400 and 700 nm. Conversion between the measurement systems is not trivial and can only be done accurately if you know the power of each wavelength in the spectrum.
It's also very important to include the ballast power for HPS. When you see something like 600 W or 1000 W HPS, that does not include the ballast. Same goes for including the driver power for LEDs.
A typical efficacy for HPS is 3 mol (PAR)/kWh. We are starting to see LEDs with efficacies above that. But there are other considerations. HPS is basically a point source where most LED fixtures are rectangular panels or strips. This is a concern in a greenhouse because you want the luminaires to block as little of the sun as possible, and current LED fixtures shade a lot more than an HPS system of equivalent light output. Putting strip LEDs directly under the structural members might be viable, but then they would need to be more powerful and/or have lower ceilings. Lower ceilings can cause issues with ventilation and temperature control. LED fixtures are several times more expensive than comparable HPS systems.
In either case it's pretty difficult to get a uniform spread of light intensity over the whole canopy. Specialized software and sometimes custom reflectors are needed to do this optimally.
Upgrading from fluorescent to HPS is a no-brainer. But HPS to LED, the picture isn't so clear (in agriculture). I think LEDs look very promising in the long run, but they aren't quite there yet. There's a reason why nearly all big commercial greenhouses use HPS.
We've barely scratched the surface in researching this area, especially the subject of what effect different wavelengths have on plant growth. At Cornell we have some upcoming experiments that will be studying the growth of vegetables under several types of LED and HPS lamps.
CO2 assimilation rate depends on concentration and species. For example, at 400 ppm, butterhead lettuce would assimilate about 0.38 lb of CO2 per ft^2 per hr. Whether greenhouse or bomb shelter, CO2 could be replenished through ventilation, infiltration (i.e. unintentional ventilation) or supplemented (e.g. from tanks). There are benefits to increasing CO2 concentration above ambient, mainly that the plants need much less light to achieve the same growth. Experiments at Cornell have shown lettuce needs about half the light if you increase CO2 to about 1600 ppm.