Home Photobioreactors: Growing Algae for Food and Profit

[Justin Boland]

I have no idea what kind of operation John Todd is running at UVM, perhaps this is already underway in Vermont. This is a roundup from a few days research and reading:

My first introduction to the concept was this DIY Photobioreactor plan courtesy of InventGeek. This was an excellent read, but it's a very specific project -- which doesn't even grow edible critters! For a more detailed background, check out this study from South Dakota University's Agriculture and Biosystems Engineering department. Their intro is pretty remarkable, considering it was written in 2000 and eight years probably hasn't changed things very much:

In the summer of 2000 research was initiated to evaluate the feasibility of scaling up the prototype PBR. Research revealed that little is known quantitatively about how the different subsystems interact and affect algal biomass production in PBR.

In other words, this remains a pretty wide-open frontier for home scientists. Not surprisingly, after 3 days of research, the single best page I found on the subject was written by some high school kids. This guide to building in-home Chlorella growing system is also from 1998! Excellent, detailed writing and clear instructions.

The good news is that initial research is promising: this has a high potential to work beautifully. Even better, you can get living culturs of Chlorella for $6.25 from Ward's Natural Science. That's "35 Students Worth" -- definitely enough to get a modest operation started. Also worth checking out is AlgaGen and especially Aquatic Ecosystems.

FURTHER READING: First and foremost, the Wikipedia entry is unusually informative. Tuberose has a very detailed rundown of the medical and nutritional data on Chlorella. Earthrise Farms is the largest Spirulina farm on Earth, and Varicon Aqua has information about the purchases you'll need to get started. Slightly off topic, but still fertile info: a detailed rundown on commercial seaweed farming operations. Finally, there's useful facts (and much sarcasm) at Google Answers and here's the publications list from South Dakota University.

[George Lisi]

Fantastic Justin. Thanks! Growing algae, along with raising edible insects, "microlivestock", are under-known ways of producing serious quantities of high quality protein, cheaply and at home, that are available to folks right now. For many of us, of course, this may be an example of how we may need to stretch our cultural definitions of relevant foods and resources as we transition.

[Justin Boland]

Good call on "cultural definitions," because it had never even dawned on me to raise edible insects. Thank you for that.

[George Lisi]

About edible insects - well first of all, they've been, and in some cases still are, important or even central to many trad peoples' diet. Anyway, webwise, I think eatinsects.com has the basics. There's some entomology prof, now quite old, who has been the doyen and champion of "entomophagy" (I think that's teh term) for many years. I think he has a website as well. Mealworms and Crickets are your basic "starter insects" apparently. They are actually supposed to be quite delicious and very satisfying, properly prepared. Bon appetit!

[Justin Boland]

Great Stanford project, building a photobioreactor from recycled water bottles:

[George Lisi]

Nice video. Get's the basics across clearly and simply. If you know anyone locally who is actually experimenting with growing algae for food or oil on a home scale, let us know! Replicable, cheap, easy to assemble and run home systems would be a fantastic boon. Algae, edible insects, these ideas for producing high quality food cheaply, right in your home, will seem much more attractive as everyone''s resources become more constrained. Be great to have as much knowledge assembled and ground truthed now, to be able to offer folks when the demand for alt solutions goes up. Thanks for this, Justin.

[Keith Morris]

Hi George,
We were growing Algae in labs at Johnson State and UVM in 2000-03, when I was producing biodiesel there. I'm not sure if the projects have been kept up or not (besides the company Scott mentions below)- I'll look into it.

[Scott Sawyer]

Hi Justin,

I just saw this discussion. sorry for coming in late. I hadn't heard of DIY photobioreactors geared toward food before. I had only focused on algae as a biodiesel feedstock. Figuring out a way to commercialize algal photobioreactors for biodiesel production is now a multi-hundreds of millions of dollars proposition. There are a lot of university-business-government partnerships that are trying to figure this out. There is really only one business-UVM partnership in Vermont that is testing a prototype algae production facility. it is connected to a methane digester and the algae uses the emissions as a food source. The algae gets harvested, sent through a centrifuge, and the oil can be converted into biodiesel.

They call this stuff second-generation biodiesel as it can be grown in spaces that don't 'compete' with food production and enormous volumes can be produced. Theoretically, the U.S. could replace all of its petrodiesel use with algal biodiesel.

[George Lisi]

Hmmm. Justin and Scott, do you know if anyone is keeping an eye on whether there is a danger of the DIY and small scale community level technology/processes becoming corporatized and legally unavailable?

[George Lisi]

Scott said: "Theoretically, the U.S. could replace all of its petrodiesel use with algal biodiesel." Do I take it that algal biodiesel is functionally similar to petrodiesel, mirrowing the functional distinctions between petrodiesel and gasoline? Any remarks on what this might mean vis-a-vis current liquid fuels and their uses, and the societal level potential of biodiesel would be great.

[Scott Sawyer]

corporatized? sure, anyway to make a buck. Legally unavailable? I have no idea why that would be the case. Yeah, biodiesel replaces petrodiesel, with a few modifications.

I'm completely unfamiliar with the DIY algal photobioreactor movement (if there is one), but i'm completely fascinated by it. I think i was indicating that algae into energy is soon to be a very major business. Here are a few examples of companies:

► Aquaflow Bionomic Corporation: http://www.aquaflowgroup.com
► Aurora Biofuels: http://www.aurorabiofuels.com/aurora_algae.html
► GreenFuels Technology Corporation: http://www.greenfuelonline.com
► Green Star Products, Inc: http://www.greenstarusa.com
► LIveFuels Inc: http://www.msnbc.msn.com/id/15250836
► PetroAlgae: http://www.petroalgae.com
► Solazyme: http://www.solazyme.com
► Solix Biofuels: http://www.solixbiofuels.com

The challenge that these kinds of businesses are trying to figure out have to do with what strains of algae to use and facility design/operation. It's still R&D phase. Why algae is viewed so favorably has to do with the volumes of liquid/material that can be produced. As an example, one study indicated that one type of microalgae produces, on average, 14,642 gallons of oil per acre. Compare this to, on average, 127 gallons per acre for canola. So, if someone was interested in cutting Vermont's diesel consumption (123 million gallons) in half, and if it was possible to get such high algal yields, then you would need 8,400 acres of space. This is equal to .68% of acres currently devoted to agriculture in Vermont. I'm not saying that photobioreactors need to be set up on farms, but .68% of space for 60 million gallons of renewable fuel replacement, with the other half eliminated through conservation, efficiency and other renewables, sounds like a bargain to me.

[Keith Morris]

Believe it or not, many of the most promising species of algae being used for this are the same species that proliferated during the Carobiferous Era, creating our fossil fuels in the first place. There isn't really any organism better suited to creating a carbon chain through photosynthesis, or at least not as simply.

The problem, however, is there presently does not exist anyway to extract the oil outside of a laboratory, or at viable scale. The norm is with Hexane.

One of the most promising applications of this technology are as smoke stack scrubbers on coal burning power plants. They are literally building 'bongs' that filter the smoke, keep the water moving, and supplying carbon through emissions that would otherwise be released directly into the atmosphere. Makes much more sense than the giant lakes they are building in the desert (algae only grows in the top few centimeters). They are showing up to 80% emissions reduction in full sun. I'll dig for the actual studies if your interested.
(I don't know why photos don't seem to work for me in replies, but here's a link:)

http://3.bp.blogspot.com/_ePegY5W6NIQ/RdarbUWNCqI/AAAAAAAAADU/eZjlM..."/>

But yes, home scale's where's its much more fun!

I only want to caution our thinking about 'energy substitution'. I don't think I'd want to 'sustain' the present motor vehicular dominance of the landscape- even if they were running on water. I'd much rather have vibrant, local food systems, than algae biodiesel shipping Mexican, Californian produce. (and I'm not saying you're suggesting this)

Good tool for our 'energy descent culture', but its important to keep things in context...

[Scott Sawyer]

That's a good caution and a suspect most people on this website have it written into their DNA at this point. When i think of a shorthand way of talking about sustainability, at a minimum it includes three basic, interacting concepts:

1) get off fossil fuels asap
2) relocalize the means of production
3) build resilience against system disturbances (e.g., climate change and peak oil)

so, we could take any example of a product or service and run it through that scenario. Algal biodiesel could fit the criteria of getting us fossil fuels asap, no matter where it's used. But if it's used to ship, say, the majority of goods and services into Vermont from out of state or out of the country, then it's not really relocalizing the means of production (e.g., food production). And if it's used to ship the majority of goods and services into Vermont from out of state or out of the country, then it's not helping Vermont build it's resilience (i.e., we're still dependent on outside sources for the majority of our food).

So, in my mind, this is A) what's fun and powerful about sustainability as a theory and set of practices; B) what's fun and powerful about Vermont as a laboratory for crafting the best kinds of local solutions.