Food Computer Cost Analysis


Hello I’m wondering if anyone has done a cost analysis of their food computer system evaluating the cost to build and run the food computer compared to the produce harvested from it. As well as determining how long it will be before the break even point, in other words the point where you were able to grow enough produce to have saved enough money to pay for the food computer build itself.


@HomeHydro: I’m afraid that your break even point will be at around infinity…:wink:
You should not be building the PFC to save money as it will not happen. Build it to contribute to a new way of thinking about food production, food safety, food quality and independancy. It’s more like charity than economic profit.


It’s the exact same think from big industry today: Business Equity!

One day, after always fallow business target and not common interest, much of the world will fall.

It’s not the spirit for start this initiative :wink:


I don’t think you’ll see a cost analysis for a personal food computer and you’ll probably have to wait until food servers are more popular or cost efficient to see one for them.


I have already been growing hydroponically for many years, in fact I have a website that’s all about promoting hydroponic growing methods for food production. As well as helping people build their own hydroponic systems, understand how hydroponic systems work, understand the different type of systems, and basically help them grow successfully.

However my focus is on growing economically, By economically I simply mean for the same or less money that I can buy it for at the store. If it costs me more to grow then to buy, then it’s not really economical to grow. So I’ll either change the method or design in how I planed to grow it to meet that goal. Now I don’t exactly expect to break even on the very first grow, but I do think about it like a business and getting a return on the investment. While I enjoy growing plants, there is a purpose for the plants I grow. Saving money at the grocery store first and foremost, then better taste because I can let them ripen on the plant, and the ability to have a supply of off season produce.

From what I have seen on this forum what you guys call a Food Computer is basically a small climate controlled grow room. Besides what I figured was an expensive and complicated build, I don’t see it really big enough to produce much produce, and even that would only be small plants like greens or herbs. Which is what really led to my question about the cost effectiveness/analysis.

Even if the concept of the food computers are simply not cost effective, I’m hoping perhaps I can take away something from your designs and methods, and be able to apply them to what I do in an economical, cost effective way to improve some common issues and challenges of growing hydroponically for most home growers.


I have to admit that as I built mine it piqued the business major in me. But the fact is the food computer is a proof of concept and It’s purpose is not for growing food on the cheap, If you haven’t watched the TED talk you should do so to gain a better understanding of the overall vision.


Thanks for the video.
I’m very familiar with controlled environment agricultural. Most home growers call them grow rooms. Commercial growers call them greenhouses. Home growers usually turn some unused space or room, basement, etc. into a grow area. But instead of needing computers and data points to control the environment, they just do it manually. Even for those that want to get a bit more automated, there are far cheaper ways to do it. As an example a standard household thermostat can be modified to turn on and off fans, AC, heaters, even open and close windows, etc. to control temperature, humidity, air circulation. My concern as well as growers isn’t in how to control the environment that’s easy, but in doing it cost effectively. In other words energy efficiently.

The major barriers for indoor growing are in heating and cooling efficiency, as well as artificial lighting efficiency. Yes I know LED’s are making strides in energy efficiency, but in reality their far from cost effective yet. Yes I know there are hydro farms growing under LED lighting, but home growers don’t have the ability to get the same price for buying in those quantities, Even so it still takes 3-5 years to break even in electrical cost savings compared to the higher up front equipment costs. For home growers the break even point is typically closer to 5-10 years. Making standard lighting options much more cost effective.

While most home growers simply circulate fresh air into their grow rooms to replace co2, simple cycle timers can be used to turn on and off co2 generators if needed. Even though it’s not necessary, if you wanted to continually monitor pH, EC/TDS/PPM, and/or water temperatures there are already continuous monitoring devices you can get ranging from $50 for one, to $200 for a three in one unit.

Yes the three needs for the plants roots are nutrients, water, and oxygen/air. In fact what makes each of the 6 types of hydroponic systems different is how they delver these to the plants roots. Most of the watering cycles can easily be controlled by simple light timers, but for some systems like a high pressure aeroponic system where very short and frequent cycles are needed, again a simple cycle timer will do the job.

I’m guessing that one of these 2 foot by 3 foot food computers cost somewhere in the neighborhood of $2,000 to $5,000 to build. But for around the same cost there are already computer controls systems available that have a complete array of all the environmental sensors and controls, nutrient injection systems, pH adjusting injectors etc, All the data is fed into and controlled by a computer system, and can even be set to notify you if any of the factors goes beyond set parameters. While not really cost effective for home growers, these computer control systems are common pace in commercial grow operations… For nearly the same cost you can already computer control an entire room or green house to grow within set parameters, compared the the 2-6 square feet in a food computer.

I guess I’m just a bit lost on the concept of overly complicating things, as well as the excessive cost to get so little return on investment. I mean it doesn’t really mater if you can grow the worlds most perfect tomato if only the insanely rich can afford to buy it.

The concept of plant biology and nutritional value and favor is currently being studied and there is a lot of information on that already. So finding information on understanding how nutrients (both necessary and beneficial), water quality, oxygen in the root zone, pH, light intensity (par/lux), light wavelengths, co2, temperatures (both water and air), humidity, beneficial microbes (bacteria, fungi, micro flora, nematodes etc.),. affect plant quality and flavor, and how their all intertwined and affect each other is already available.

What would make the concept of growing hydroponically within a controlled environment, and able to produce year round more attainable is energy efficiency. Making d=current methods of controlling that environment cost effective. That would have a far more reaching and beneficial affect on global food production. I’s not that growing within a controlled environment is a new concept, it’s that the current methods of controlling that environment limit how cost effective it is to do so.

If you can figure out ways to improve the efficiency of heating and cooling the air and water temperatures, as well as improve the efficiency of artificial lighting methods. That will go a lot farther in advancing hydroponics for food production than anything else, because those are the two biggest issues facing hydroponic growers, both home growers, as well as commercial growers.

There is another point where I think technology can be improved. Currently EC/TDS/PPM meters can only tell you the total dissolved solids in the water. That doesn’t tell you anything about the balance of mineral salts in the water. Currently the only way to find out the balance of specific dissolved solids in the water/nutrient solution is through costly lab testing. If you could design a relatively inexpensive handheld meter that could tell you the specific elements in the water, and the specific amounts of each, that would go a long way in diagnosing nutrient issues and improving plant quality for the average grower.


I am not going to argue with you HomeHydro as you seem to have far more knwodledge about growing than I do. You are concerned about the cost efficiency of the system in order to make it available to many and I agree with your concerns, however, it is up to those who can afford these ‘unefficient’ new methods in order to refine the product to make it available to others. Think of Tesla who came up with an extremely expensive model that had no other benefits than ‘being green’. The succes of the model made the development of a new model possible that will be available to many more.
I am convinced that household appliance makers are already looking at this market and they will launch products that will do what our PFC does in a much more efficient way. It’s just a matter of time…
The current bottleneck for the costs is the high price of sensors and actuators. These will come down as soon as the volumes are increasing. The price of the RPI is futile and the software will at some point be more user friendly as it is now. For the energy cost: this is something we cannot influence. LED maybe slightly more efficient in the future but that will not have a dramatic inpact on the ROI. It is also very depending on your geological situation. Some need to heat ip, others will need to cool down. In some areas energy is abundant (Scandinavia or Middle East) in some ares it is expensive.


Hello Peperoni,
No, I’m not concerned with making the food computer design affordable in order to make it available to many people. Nor am I concerned with building them to sell. I’m sure some day there may be a practical and cost effective application for larger versions. Even now they have very similar grow rooms (food computers) on the international space station to grow fresh food that would be otherwise extremely expensive to ship to them. Antarctica research stations are another example where small computer controlled grow rooms are used to feed the people station there since shipping in fresh produce is risky and expensive.

But building grow rooms are already common practice and easy to build, the only real difference in what’s already being done on a cost effective level for home growers, and in a cost effective computer controlled level for commercial growers, and between the food computers that I can tell is the food computers use small test grows to take data extensive samples. Like test subjects. Their not really practical for growing food, but their main propose and primary function is collecting data.

The question is will that collected data help advance hydroponics? I’m sure it will since the more we learn about how plants respond to their environment helps us to grow them more efficiently and cost effectively. That’s why there are already many university’s doing controlled environment agriculture as well as regular study’s and publishing their findings. Their teaching future farmers a greener more environmentally friendly way to farm productively and cost effectively while using less water and land resources .

My main interest in the food computers isn’t building them and growing in them, making them available to the public. or even in the data your collecting. But to use your Tesla analogy, perhaps there is some technology your using or can develop that can benefit existing methods. In other words instead of building a whole Tesla car, there may be parts of that car (like an alternator system or radiator system) that can be applied to already existing cars to make existing technology and methods more efficient. My interest is trying to understand your systems, and if there is a way to use the technology to make what’s already being done more efficient/cost effective.

I don’t know what your using for your heating and cooling systems to heat and cool the air as well as nutrient solution. I don’t know if you are testing the nutrient solution for each and every mineral salt, and monitoring the ppm values of each specific element. Much less if that could be made into a hand held version of such a device. In fact I don’t know much about anything to do with you electrical systems and environmental control systems for your food computers. But I’m hoping there might be some things you have developed I’m able to adapted to help make standard methods more cost effective and productive for some of the more problematic issues in growing hydroponically. The three major hurdles hydroponic growers are:

  1. More cost effective/efficient ways to keep the nutrient solution temperatures under 80 degrees, even when outside temperatures are over 100-110 degrees.
  2. Reducing electrical costs from artificial lighting needs when growing inside, as well as water cooling systems.
  3. Being able to test the PPM levels of each specific element in the nutrient solution without costly lab testing to identify nutrient deficiencies and toxicities.


@HomeHydro: I totally agree with you that the purpose of this forum should be to improve the design of the PFC and power consumption is defenitely something to take into consideration. Having said that, I also think that we will never (not for a long time) be able to bring down the energy costs to a level that vertical farming becomes a commercial alternative for industrial farming… unless the price of ‘industrial farming’ will be calculated in a fairer way: Now the costs for government funding of agriculture, the ‘sponsoring’ of transportation costs and the abuse of land by monoculture etc are carried by the tax payers and not by the consumers. As soon as we can change that I am convinced that small scale (urban) farming becomes more and more attractive.
Coming back to the more tangible topics:
There are three methods to reduce energy costs:

  1. lower purchase cost (indeed: solar power, wind turbines etc)
  2. increase efficiency: for that the hardware suppliers should put more effort in making their products more energy efficient, like the led lighting, the fans and the heater.
  3. use less energy: Your question about cooling down air and water temperature (something I don’t need here in NL, yet) brings a technique into my mind that was already used by native americans: a wet cloth in the wind on top of a chimney was an air cooler avant-la-lettre in yesterdays. You could consider hanging a cloth in front of the circulation fan and dip it in a small bucket of water. The water is soaked into the cloth and evaporated by the air that is sucked trhough it by the fan. This will bring down the temperature of the air and increase humidity at the same time. I don’t know if anyone tried this before in the PFC but it is certainly something to consider, I guess.

About your point nr.3: I guess we either have to wait until someone comes up with more affordable sensors or start developing them ourselves. I know that the HAS (Higher Agricultural School) here in NL is actually working on an all-in-one sensor that monitors the water for a very affordable price. It will take years though before is enters in production phase. Mayby MIT is looking at this as well ?? it will be one of the drivers for the succes of the PFC.


Hello Peperoni,
OK, well I can only assume that with all the money you guys spend on the “food Computers” that either you don’t have any systems and control’s in place to control air and water temperatures, nutrient, etc. or your not just willing to share information about how you go about it and how effective it is.

I live in Arizona and controlling air and water temps is essential to healthy productive plants dealing with the elements, and I’ve been researching and designing cost effective methods of doing just that for over 8 years. In fact I have even written an article called Nutrient Solution Temperature is Important describing many ways to keep nutrient solution temperatures under control.

The wet towel over a fan technique is really just based on a swamp cooler, and I have built many swamp coolers. Swamp coolers are a common method of cooling in commercial greenhouses. I have even built a subterranean cooling system, which is essentially a geothermal air conditioner that uses the cool ground to pull heat and moisture out of the air as it circulates through tubing underground so it comes back up cool and dry, while using no more electricity than a simple fan to circulate (pull) the air through the tubing.

Just because I’ve learned many ways to control the growing environment doesn’t mean I plan to stop looking for more cost effective methods, and/or ways to improve on current methods. I was hoping since you guys put a lot of time and money into your food computers, I might be able to learn something from what you guys have done and are working on, but I’m getting the feeling that either there isn’t anything to learn from this forum, or the people here aren’t willing to share with outsiders.


Hi HomeHydro

I am very sure that there is no secrecy here - on the contrary.
But, the concept is fairly new, with not a lot of FCs built yet.
So, it might take some time before revolutionary designs see the light of day.

I figure most here are pretty new to growing anything indoor, and thus on a learning curve, where a lot has to be figured out. Tech interest, and food security interest. And maybe not choosing the most efficient solution.

BTW, useful that you put the economy of the project in perspective.
I have used your webpages a lot, they are very useful.

kind regards
Øyvind Strøm


Hi Team –

Does anyone have a ball park figure for what it would cost to hack this space as food computer / server ?



Hey guys,
As I mentioned in a post on another thread, I am a high school student from Canada who is working with a team of teachers and students to build a PFC. Last week, I went through the Master BOM and added the prices specified by the links, getting a total of about $3200 US ($4300 CAD, not including shipping). However, this is well beyond our budget. Does anyone know any hacks or cheaper materials we can use in order to reduce the price of the PFC and get it within our budget of about $2000 CAD ($1500 US)?