Where's the cooling aspect of the food computer


I understand about the rooftops but we have to consider ALL available space to determine the boundaries of the system, what works what doesn’t. A goal is to same what kind of adaptable,economical,insulated growth area can we place where and what will it’s probable output capabilities be. That’s the one of the points of getting reliable telemetary from a small space ( farm computer) then seeing what it takes to scale it up to larger spaces, what materials do what, how does the growth medium work under different temps, water quality,even pressure ( coffee tastes better grown at altitude ) etc. Once you have some idea of the effects on an area you can find which bill of materials will be suit your budget and goals. Right now we have people growing lettuce out of gallon milk jugs with a cheap T5 light from home depot. The goal here is to get people thinking about this in offices ( yep they are growing there as well), school etc. It’s a system called Kratky ( see videos above) and is low maintenance.

Solar energy is market driven so the day it becomes economical to use it will be the day you see it grow like a weed, low oil prices ( and probably staying low for some time) aren’t going to help it’s case, ho hum… As to the conference, please try and attend there are some excellent speakers and Dr Nate Storey seems to have some interesting ideas, that may bear on your apartment space issue. He grows UP not sideways using grow towers, you could make one yourself ( just an example ) https://www.youtube.com/watch?v=663kBnFLBBM&list=PLbiYoiwgZY248_LGpNI872VHAWmZPxHm6


As a hydroponic grower also, I would urge you to reconsider your ideals on TDS and pH, both of these pieces of information are invaluable, and should be measured as often as possible. TDS and pH should first be measured when evaluating your water source for any: hydroponic, coco, aeroponic, or soil grow. In the best of circumstances a reverse osmosis system should be used to to get your PPM down to an acceptable baseline, but I have seen many water sources where it was not needed (without this measurement you are flying blind). Without getting your baseline PPMs at an acceptable measurement you will be robbing crops of valuable available nutrients before you even start. The advantage a PPM measurement gives during the growth cycle is a window into how effectively the plant is up-taking nutrients, and how much nutrient solution should be added to the system. Without this piece of information the grower is simply taking guesses on how much solution should be added to the reservoirs and may be inadvertently locking out nutrients.

PH is the other variable in this equation, as you well know pH is the driving factor for nutrient uptake into the root system. In order to determine how much acid is needed an initial measurement of the water source should be taken, and of course measurements as the pH is adjusted. For the systems I have built the electronic pH meters have been a great value. The value add the electronic meter brings is repeatability, with the advent of newer pH meters with less requirements for recalibration a constant stream of pH data is not only inexpensive and accurate, but imperative to optimizing and notifying when a problem arises. A hydroponic grow can turn south rather quickly if the pH of the system fall out of balance the sooner the problem can be identified the less stress on the plant. Creating a hydroponic system that just grows is not a hard task, but for the low cost of sensors there is no reason not to have an optimized hydroponic system.


This baby is sitting in my living room until I finish it :sunglasses:


OUTSTANDING! I wish you well with your enterprise. If you get a chance swing by that conference to chat with the speakers. I’m betting that they would be very encouraging AND, more practically, might be able to help you get some components to finish this off. Many labs have parts they don’t know what to do with and sometimes just give them away. The speakers are the people with the contacts in the universities. Never hurts to ask. Remember their mandate is to educate and stimulate. WELL DONE.


Nice discussion guys, in my opinion you are both right since the cost effective part is important but also the self-feed-capacite-skills is important. I’m now 10 years experience in the greenhouse industrie and in my opinion it survives because so far is the best option that exists, however in energy use is completely inefficient, except for the closed greenhouses, but the investment is huge € 1,5 million Euro/hectare just for the greenhouse an equipment and still you have to move the product al over the world producing huge amount of contaminants and in my opinion the worst of all monopolizing the food producing.
The PFC initiative in my opinion gives who is interesting the tools to start learning about producing their own healthy food in order to escale it eventually to a food server and become independent in at least vegetables fruits and some grains. The thing of making it cost effective will depended on each one, since each area have their own problems/advantages.


Regarding the temperature control, besides geothermal energy, it is also possible to give a peek to developments presented by participants in the solar decathlon contest (solardecathlon.gov). Eventhough that contest is focused on housing, the aim is similar: temperature control in a space.


It appears the cooling aspects for PFC v2.0 has not yet been determined. The Build of Material for version 2.0.0-beta2 that was posted 4 days ago does yet not list a part number. The description lists a “Kipp Kitt Chiller Compressor” but when visiting the manufacturer website, the price is prohibitively expensive (USD $5,000). Thus, I believe that they are still looking to source a small footprint chiller (which apparently is is challenging).


thanks for bringing up this conversation. I think it’s critical to have critical voices - especially from those with a strong background in growing hydroponically. I concur with @135711 - both aspects are important.


For folks who haven’t seen this stuff, more information about cooling for the PFC v2 design is available now:

  • Jake’s forum post on 6 Jan 2017, “OpenAg™ Personal Food Computer v2.0 (beta) [Documentation Release]”, mentions that:

    The Chiller Unit is being made by an awesome maker named Kipp who has been experimenting and innovating on small scale DC chiller units for a few years (among doing many other awesome things). He has been helping us achieve 200-300W of cooling so we can more precisely control the temperature in the food computer chamber in an energy efficient way (compressor based instead of thermoelectric cooler based). He is currently in the process of scaling up his operation to make this unit more accessible. This unit is interesting because while many plants will grow fine in ambient environments, being able to actively control the temperature and go beyond the ambient temperature range is a key feature for the personal food computer to be a precision agriculture device. If you want a very near term solution, mini fridges / freezers and water coolers also have to solve a similar cooling problem.

  • On GitHub, the OpenAgInitiative/openag_pfc2 repository has design documents and build instructions including:
    - The main build instructions document
    - Build instructions for the chiller sub assembly including a photo of the chiller unit
    - Sub Assembly bill of materials including a "Chiller Assembly " tab


This Compressor based Aquarium Chiller seems like it would work well at a reasonable price - except it won’t fit in the food computer frame.

Building, growing and designing in Riggi's "garden"