Over the last few millennia farming and the production of harvestable plants has grown in leaps and bounds. Starting from simply planting seeds to developing wheat and corn through ‘preferential’ planting to today’s controversial GMO techniques, the world is now able to feed more people than ever before. However, there is one aspect of farming that is still relatively underdeveloped, the implementation of growing in three dimensions. While it may be true that some cultures still use a tiering system to overcome the bounds of limited flat ground, this in of itself still doesn’t take full advantage of using vertical space. But with recent developments and social movement behind it, this new idea of pushing agriculture towards the sky is changing the way the world thinks of farming. The following is an overview of the design and prototype building processes that are a culmination of two years’ work for the EPICS team associated with REAP

The EPICS team immediately planned for space within the greenhouse to be devoted to a vertical growing solution that would be able to grow with a system as needed. It would need to do this all the while being: cost effective, made of easily accessible materials, and easy to construct with limited knowledge and tools. Taking inspiration from the many different iterations which can be found online, the established water team came up with an initial design and parts list. Great care was considered to prevent any infringement upon any intellectual property which may be copyrighted, or sold for monetary gain. The intention wasn’t to simply copy someone else’s work but to create something that would work for the situation unique to Tolani Lake’s needs. The resulting model is shown below:

 

 

Consisting of basins in staggered, or masonry style, orientation each tower would consist of a 10-inch diameter PVC pipe. A primary basin would hold the associated pump and all basins would be plumbed together. Water distribution would be handled with a PVC manifold being feed by the pump. Gravity would then be the force behind the output of the manifold and internal steel lath would force the incoming water towards the sides, providing the plants with water and nutrients. The implementation of such a design for the purposes of Tolani Lake, however, was quite simply not feasible. In fact, nothing worked on the initial design. After another 5 months and other iterations, water distribution became a matter of optimization rather than proof of concept. Iterations up to the current model can be found below.

Idea

Status

Status Note

 1. Steel Lath w/ PVC

Failed

Water fell straight through lath

 2. altered PVC manifold

Failed

Not enough water pressure for application

Drip Irrigation

 3. Drip Irrigation Couplings

Failed

Too source pointed / Not enough Uniformity / Multiple Variants

 4. 3/8" hose punctures

Failed

Not uniform / reproducible enough

 5. 1/4" hose punctures

Failed

Not uniform / reproducible enough

 6. Drip Irrigation Soaker Hose

Failed

Not enough pressure / Multiple variants

 7. Drip irrigation 360° Emitter

Semi success

Prone to failure

8. Epoxy Puty

Semi fail

Prone to leakage

8. Larger Pump

Semi fail

Still not enough pressure

9.Different Emitters

Semi success

Clogged Easily

10. Y filter + Pressure Gauge

Semi success

Too low pressure

11. Larger pump / Different reservoirs

To be determined

 

 

While the water distribution was being resolved the team needed to find out a way to hold the plants on the side of the ‘towers’ themselves, this meant cutting holes at a 45-degree angle on a curved surface. After futilely trying to cut the holes with a hole saw connected to a drill a decision needed to be made. Since the PVC manifold for the water had already failed it was decided that the team would use the left over 2-inch PVC piping and cut them into lengths that would accommodate a 45-degree angle. Instead of trying to use just a drill, the 45s were used as a template, holes were drilled then templates cut out using a skill saw. The team then used a combination of PVC primer, PVC glue and silicone caulking to attach the ‘45s’ to the side of the tower. While this is not ideal and will most likely not be the final technique used, it will suffice for the prototype. Finally, after hooking everything up we have some preliminary results to show proof of concept.

 

The current implementation is organized in a linear fashion, instead of staggered. This means that the greenhouse could potentially allow for more towers due to a more functionally modular design. In addition, the cost of materials and the knowledge to use said materials is also greatly reduced. The prototype, as of this writing, has a water system that is ran by drip irrigation tubing and commercial mister emitters which spray in a full 360-degree pattern. This means the water setup takes a matter of minutes, not hours for the glue to dry and cure. Future work will be focused on optimizing the system as other problems have surfaced. Additional update blog posts will be released during the refinement process, so stay tuned.