*And it's grown in household urine, which is hard to beat for efficient.
http://shareable.net/blog/is-algae-the-shareable-answer-to-food-energy-crises
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AC: What's so great about algae?
AB: Algae is a way to grow really high quality food in a small area, on the surface of a body of water or in wastewater. Or you can grow algae in dilute urine which is an easy way to get the right nutrients and reduce your impact on the environment.
Most marine biologists consider that the number one danger to marine life is utrification, an excess of nutrients in the water from agricultural runoff due to application fertilizer. When it hits the ocean or lake, there are massive algae blooms. When they decay, they wipe out oxygen and everything dies.
If you can find a way to keep nutrients out of water, you reduce the size of dead zones. You can create controlled algae blooms, harvest algae and eliminate nutrients that way. Or you can take wastewater, give it to algae directly and absorb nutrients. You come out with clean water, fuel, food, fertilizer and extra oxygen. And on a small scale in your own house if you grow it in dilute urine, you reduce the fertilizer load on the local ecosystem.
AC: Tell me about algae as food. Why are people so into it? (((They line up around the block, in my neighborhood.)))
AB: The idea was first proposed in the 1930s in Germany. They were trying to develop it for growing food. You can grow a lot of food in a small area. It's extremely nutritious on a gram-for-gram basis. You can mix it in with other food. It didn't take off until spirulina in the 1970s. Now there's chlorella.
Normally you get spirulina in a powder or pill form. It's grown in large outdoor ponds normally, and you sieve it out of water. It's kind of special. It grows in corkscrew filaments making it relatively easy to strain out of water using a special fabric. Most other kinds of algae are too small and roundish, very difficult to filter.
Algae as a food is extremely healthy. It's high in complete protein, antioxidants, omega-3 fatty acids, and it's effective against infections. It has defenses against viruses and you can acquire defenses as well. It's good to protect against environmental toxins. There were dozens of experiments where they fed rats a regular diet and another group with spirulina. They exposed them to mercury, lead, pesticides, radiation and mutagens and found that spirulina-eating rats do much better.
In powder form, spirulina's great, but when you want to eat a blueberry, you don't want it powdered. You want it fresh. You can eat fresh spirulina that's basically alive. It tastes better.
AC: What does it taste like?
AB: The problem with most algae is it tastes like seaweed. A lot of people are not turned on by that taste. I think it's really good in certain dishes. When you eat it live, fresh, the taste is much lighter, creamy, and buttery. You can spread it on crackers. We mix it with brown rice and guacamole so it's vegan. (((Personally, I prefer "freegan" algae salvaged from strictly anticapitalist puddles of wastewater.))) The easiest way is in carrot juice....

(((The thing I like best about algae (among its many enticing benefits) is that it might be a "crop" you could successfully automate.)))