Sustainable bioreactors to feed the planet and generate wealth.

A few days ago, there was a post on the /r/soylent subreddit that caught my interest and got me thinking (in case you don’t know, Soylent was designed to be a nutritionally complete meal replacement, much like Keto Chow is, but with much higher carbohydrates and sugars). The original post was talking about how Rosa Labs, the manufacturers of Soylent, had changed and lost the original vision of the founder. Among other points, they talked about how Soylent no longer used oils made from algae. One of the comments REALLY got me thinking:

I want soylent to be made entirely from algae and synthesised efficiently and sustainably in bioreactors in huge factories thereby providing cheap healthy food for everyone.
-VividShelter

So I started thinking what would be an ideal set-up for synthesizing food that would NOURISH people: have ample amounts of quality proteins and fats, along with vitamins and minerals. Ideally, I’d want it to sequester carbon and build soil health as part of the process. Here’s what I came up with:

1. With algae, you need a lot of water and sun exposure, that’s a little hard to do with much of the surface of the planet. I think a better approach would be to grow cellulose and use microbes to process it. We have huge areas that are covered in trees, rocks, and grass that isn’t farmable. When you see graphs of the land usage in the United States, the biggest part is in pasture/rangeland – that would be perfect for this since it’s generally rocky and hilly or too dry for farming anything but grasses.
2. By using grasses, we get the benefit of carbon sequestration and soil building. When grasses are cut down and then grow back, they not only grow UP, they also grow DOWN into the soil. This added biomass is what made the rich soil of the great plains. Growing crops like corn and wheat tend to deplete the soil (which is odd, since those are grasses too). Regardless, it’s a way to build the soil, shove carbon into the ground, and produce cellulose for our bioreactors.
3. Using grasses like this, it would be a good idea to have the bioreactors mobile. They would go around from area to area with a harvesting mechanism to cut down the grass and then start it processing. Cutting the grass is important because you need to either cut it or burn it or it won’t grow (and build soil and all that). The movement and harvesting would be best powered by the fermentation process of the reactor so it’s self-sustaining, just needs a little maintenance and some water to move the reaction along.
4. The reaction that’s going on and the byproducts of it will likely produce some “greenhouse” gasses – but the cool thing is that any produced will be the result of previously sequestered carbon. Everything going into the reactor used to be water, sunlight, and carbon from the air. If some comes back out, it’s really not a big deal since it’ll get captured by the grasses again anyway.
5. This is a perfect use for the grasses because vertebrates (like us) cannot break down cellulose – no vertebrate makes the enzyme necessary to break the bonds and turn cellulose into simpler sugars, thus we use microbes that can easily do it! We don’t even need to genetically modify these since they already exist in nature.
6. Here’s an important part: when you talk about protein in vegetable/plant sources, that’s what’s called “crude protein” and it’s measured by looking at the total amount of nitrogen in something and ASSUMING that all nitrogen in it is part of amino acids. Well, that’s a frankly stupid assumption because you can often have nitrogen in other molecules or in proteins that us humans can’t utilize unless it’s processed by a bacteria or other specialized microbe. The nitrogen in the grasses will be converted into amino acids by the microbes in the bioreactor. Research that I’ve seen on the subject indicates that there’s a greater than 100% return, meaning that for every unit of crude protein you put into this sort of reactor, you can potentially get 1.2 or higher back. It’s like printing your own money! Except it’s protein. Whatever.
7. If we’re dreaming big, it would also be ideal to have mechanisms in place so that (again, powered by the reaction with water, oxygen, cellulose, and some salt and stuff) we can have the reactors self-replicate. It would probably require the use of biological reaction vessels and other stuff that could be made from the byproducts (proteins!) of the reaction because self-replicating metal isn’t really a thing.
8. Once we have them replicating like that, they would be an amazing way for less advantaged people to generate wealth and improve their lives. These reactors really are like printing their own money! Once people have them and are enjoying the benefits that come from them, it would be a pretty stupid thing for people in more affluent countries to tell them they should stop using the bioreactors because they somehow, inexplicably damage the environment. That’s ludicrous! They only way you could possibly claim they were damaging the environment is if you claimed that the amount of water used by the reactors included ALL of the water that falls on ALL of the grassland used to grow the grass, and you looked at carbon emissions without accounting for the carbon going into the reaction in the form of cellulose. Seriously not an honest conversation here.
9. Because the reactors are mobile, storage of the reaction byproducts is going to be a challenge. Aside from the waste =) we’re talking about the human USABLE byproducts here, we’ll get to the waste in a second. Some of the byproducts will be coming out in a liquid form that’ll have proteins and fats and all that, but some of the byproducts would be used to form the chassis and other structures of the bioreactor – every so often you’d be able to “harvest” the older bioreactors.
10. OK, the waste: again, they’re mobile so the majority of the solid and liquid waste from the reactions would be deposited right back onto the grassland so they can be utilized by the grasses to… grow more grass. It would be all of the stuff that the bioreactors didn’t use but that the grass needs to grow. Pretty much a perfect match!
11. Dreaming big here again: let’s fit them with a sensor package and rudimentary Artificial Intelligence so that they can avoid obstacles, do the harvesting autonomously, handle the self-replication, and more – all without needing humans to do very much at all except maybe transport them around if needed. In fact, a few would probably get lost and eventually “go wild” – just imagine free-roving autonomous bio-reactors wandering around breaking down grass and water into more bio-reactors. It’d be a sight to behold. Having the AI might cause a bit of a moral dilemma for people that have qualms about harvesting something with any intelligence – it’ll create some interesting discussions – just so long as we don’t get bogged down arguing about supposed environmental issues, that was covered in #8

So, sounds like a cool project right? I suspect it would take quite a bit of R&D and time to get it working just right, but once we have these free-roving autonomous bio-reactors working it would be an amazing thing. Until then, we should probably just better utilize ruminants.