Introduction: Algae in Space
(Entering in Professional Category)
Space is a very interesting place. In space gravity is technically negligible so you and other objects float as though weightlessly. In reality there will always be gravity pulling matter towards matter and the international space station is actually affected by a good percentage of earths gravity. Interestingly the space station, and most satellites, are in constant freefall (a very complex system of inertia that keeps an object moving, yet not plummeting to earth) as it orbits the planet. This freefall makes it seems like there is no gravity and provides weightlessness. This causes a number of problems with everyday tasks such as brushing your teeth, going to the restroom, eating, and growing food.
Microgravity makes growing plants difficult, growing seed plants are even more difficult. Soil will not stay in place, which means plants root systems will not have structure for growth, they wont be able to absorb nutrients naturally, or keep warm. Water coagulates into globules in microgravity and there is no guarantee that the plant will absorb them. With everything floating you have to get creative with your materials, either by strapping them down, or modifying them so that floating does not affect its use. You also want to utilize there bare minimum of materials, the more things there are, the more likely they are to break. On top of that, everything you bring has weight and also has to be stored, keeping it low profile helps cut down on the weight the spacecraft needs to carry and allows space to be used for other things at different times.
Keeping your soil, plant and water all inside a tight-knit container might be able to fix the problem of weightlessness, but that might not be space and material conservative. You could fill the box completely with soil and inject water into it and try and grow potatoes, but eventually the soil would become depleted of nutrients and nothing would grow. My solution solves all these problems and more.
Growing food in space will help two things. One it will provide a change in meal for the astronauts in space and help diversify their nutritional pallet. The second will turn carbon dioxide back into oxygen allowing longer trips to be held. Admittedly this will not go far in the aspect of replenishing food stores or oxygen levels fast enough to stay in space much longer but it will help pave the path towards the goal of extending space exploration time limits.
My reasoning for developing this idea is not for space though. This way of farming is pretty much vertical farming which turns 1 1/2 square feet of (land) into about 20 square feet of land. I hope different agriculture companies will see this and utilize it in their own practices so that we no longer have to use 60% of our land just for farming and ranching. If every farm utilized this practice, or something similar we could turn that 60 percent into something more like 10% or even less. The rest of the land could go back to natural forestry and actually be of use to our planet then. On top of that, this type of farming could be used literally anywhere, in the city, a desert, or as you can see, even in space. This gets rid of the problem with distribution of food and accidental waste. This solves so many problems yet I have only seen about two countries using vertical farming on a large scale.
Please, Please use this information and make your own gardens based off of it. Our Planet Needs Your Help
15 - 18" x 18" Sheets of plexiglass
10 - 1.6" x 17.25" x 17.25" plastic bags with nipple connectors
11 - 54" full spectrum LED strips
Several cloth strainers with stopgap valve
Minerals (Sodium bicarbonate, salt, potassium nitrate, calcium chloride, urea, iron and ammonium and magnesium sulfate)
1 - Compact water pump + aerator
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Step 1: Overview
Now to the real project. My design utilizes algae, Spirulina to be exact. I chose algae because it is a very resilient organism. Not only is it resilient but it is also an incredibly simple organism. Algae multiplies at an exponential rate yet requires less resources than most other plants. You can reuse the water it grows in and spirulina is practically a superfood. Growing algae solves all problems mentioned earlier especially the water one. Placing the algae in bags prevents the water from going in random directions. LED strips encircling the entire ecosystem will provide light and heat if needed. Having a controlled environment (the plexiglass box and bag) you can inject nutrients whenever needed or harvest as much as you want as often as you want. There is also no need for soil and you get the best usage of space compared to growing ANYTHING else. On top of that, you can completely empty everything and break down the garden so that it is COMPLETELY flat, saving space when not in use. The materials used are acrylic so they are naturally shock and heat resistant which is good for resisting liftoff and the heat created for the full spectrum LEDs. The tubes will be able to have a strainer attached so you dont lose any resources when harvesting. LEDs save on power usage and if you use an aerator it will help the growth process more. Natural vibrations/aerator circulation promotes growth of the algae.
Spirulina grows more quantitatively, grows exponentially faster, makes the best use of space, does not need soil, can reuse water, requires less nutrients, is a superfood and provides many nutrients, and is 400 times more efficient turning CO2 into oxygen than almost all other plants
Step 2: Measurements/Design
The dimensions for my prototype are only 18X18X18.25 which allows space for other items to be put on the sides like LEDs and the aerator, or in case you would like the hoses to be attached on the outside, or motors attached so that the algaes growth is promoted more.
There is a total of 15 precision cut pieces that fit together like a jigsaw puzzle. The material used would be acrylic because it is heat and shatter resistant. Acrylic is also inert in solid form (less likely to have chemical problems) and does not yellow, which means the photosynthesis quality will not degrade over time. Another perk is it is classified nontoxic under OSHA regulations, safe under most ambient temps but softens at higher temps but wont melt until 320 degrees and easy to clean.
There is one Front Piece that has a opening slot that can be used to open of the box. The Top and Bottom are the same solid pieces. The last three Sides are also the same pieces that have slots in them every 1.5 inches. There are also nine Dividers that have cut notches cut out to size to fit into the slots of the Side pieces.
All the pieces are .25 inches thick, could be made thicker but that will change the design some. All other dimensions are in the included files.
In between the dividers there will be plastic bags, made to fit with nipples so that nylon tubes can be attached. These tubes will then be able to be guided through the slots in the Dividers to the aerator that can be optionally attached. The bags will be filleted rectangular prisms to maximize how much algae can be harvested. The bags will be about 17.5X17.5X1.5 inches which means there will be abour 7.5 liters of water/algae there.
LEDs will be attached on the outside of the box facing in from 3 sides encouraging growth on each of the ten levels
Overall this is an incredibly simple design that maximizes the amount of space that can be used and when not in use can be taken apart and stored in a space of about 18.25X18X9 inches. Also if anything breaks it is easily replaced or fixed with what is already aboard.
Step 3: Spirulina
Spirulina is a biomass of single celled microbes called cyanobacteria (Blue-Green Algae) that can be eaten. Just like other plants it creates energy from the sun through photosynthesis. It is a incredibly nutrients dense superfood that has vitamins, minerals and proteins and almost all of the essential amino acids. Algae like this has more protein content in it, gram per gram, than other meats or protein rich plants. Some minerals that it contains are Magnesium, Potassium, Calcium, Niacin and Iron, all of which are required for a balanced diet. Even though it is packed with nutrients, it must still be paired with other food so the body will absorb it more equally, so it is not a replacement just yet.
In addition to being nutrients rich, spirulina can grow in extremely harsh climates with extremely alkaline water that nothing else can live in. Of course in order for human consumption you would need to make the water safe again but allowing the spirulina to grow in harsh conditions means that other potentially harmful organisms like other algae that produce toxins or bacteria wont survive. Harvesting it is as easy as using a cloth strainer, and eating it as is, or drying it to be used later. With each of the ten bags having a volume of 7.5 liters, a total of 75 liters means it will take about 2 weeks before you can harvest. This is based off a standard that is set by using a one liter started kit being put into 2.5 gallons of water. It takes two weeks for it to become thick enough before you can double the culture (put more water and volume in the tank). We are doing everything multiplied though, we will be using several smaller cultures so it will take only two weeks before harvest for ALL of the spirulina. In reality for your daily diet you would only need to harvest about ten teaspoons MAX which you could do every other day, for the entire crew.
Growing like this would be safe up until about six months or so when the waters pH will have risen too high for decent growth. But no worries, all you have to do is harvest the spirulina, and switch it to a new medium (different water) and add some chemicals to lower the pH of the old water. Also when harvesting the algae, you would need to add a bit of iron, and base nutrients to the culture for better growth.
In summary, Spirulina grows fast, grows densely, doesnt require anything other than light, nutrients mix, and water, and is literally one of highest nutrients packed superfoods ever discovered. Plus it goes great on toast.
Step 4: Standard Operation Procedure
First off the box comes flat stacked, you just put some of the sides together, put the shelf dividers in and then put the rest of the sides and front on.
Put the bags into the shelves and attach the tubes to the and to some ball T-Valves and to the aerator (if you have one) or the pump (which promotes growth)
Fill the bags with water and the Spirulina starter culture (one liter). Each of the bags should have one liter spirulina mixed in with about 6.5 liters of spirulina.
Attach the 11 LED full spectrum light strips around THREE sides leaving the front clear so you can access the bags. Technically you could use more or less LEDs but i figured "two" strips per level would be more than enough.
LET IT SIT AND DO NOTHING ELSE. Ok you can do that, but it would be good to take a small sample of your spirulina and look at it under a microscope to make sure nothing looks fishy. That and check on the pH level to make sure that everything is ok on that front too. If the pH is too high or low, the spirulina wont grow as fast, and it can sometimes allow something harmful to grow alongside it.
When ready to harvest (two weeks for this volume) open up the ball T-Valve and attach a strainer to it and filter out the spirulina from the water. Close the ball T-Valve up again (this time opposite of where it initially started) and inject the water back into the system.
Repeat for up to SIX MONTHS
After six months passes, harvest the spirulina, and then switch the water with nice and fresh water and put some spirulina back in
Participated in the
Growing Beyond Earth Maker Contest