1  #+TITLE: aeroCAES
 2  
 3        #+begin_src markdown :file ./README.md :exports code :results silent
 4  [MCAES](https://www.lowtechmagazine.com/2018/05/ditch-the-batteries-off-the-grid-compressed-air-energy-storage.html "Low-Tech Magazine") (Micro-Compressed-Air-Energy-Storage) is a young idea and has yet to inspire any proof-of-concept *in the field*, as it were.  To this end might we attempt to formulate something of a self-contained system with a limited set of considerably deterministic parameters--a *limited case proof-of-concept*.  One such formulation might be had by simply switching focus from the voracious complexity of human life to the simple necessity of botanical cultivation.  In short, if one were to store only enough energy in the form of compressed air for the purposes of semi-autonomus botanical cultivation of a given scale, one could well and quickly determine or demonstrate the efficacy of MCAES more generally.  Aeroponics is exceptional among agrarian techniques in its capacity for both boosting production and conserving resources, and by virtue of its manner of accomplishing both does it even manage to decouple a crop's production from most environmental considerations, suited as it is to climate-controlled auspices; owing to this among some of its more technical particularities, it is perhaps the most uniquely suitable means by which to assess the viability of MCAES.
 5  
 6  Such a considerably deterministic application offers ample opportunity to tailor its approach in a way more optimal than merely exceeding a household's maximal energy demands in perpetuity (invariably the foremost consideration of the popular imagination), but our arrival at this alternative is not so simple to elaborate and would prove indeed quite tangled up with the considerations of MCAES more generally.  For instance, the availability of energy (electrical or otherwise) can only be reasonably assured by the systemic and perpetual dissipation of a kinetic form thereof (usually thermal, such as in the case of combustion, steam driven turbines and so forth), but other more intermittent sources of energy production can be had freely and in great abundance, yet *only* whensoever they *can* be had; such intermittent sources of energy production are seldom so generally applicable not to require some form of conversion at some stage of a given system so complex as that required by botanical cultivation (certainly as regards particular climes and scales), and so already must we consider what form of energy is most common to the entire system, much of which is indeed kinetic in the sense of requiring air pressure.  Our system therefor stores pressurized air (whether pressurized in a way powered by photovoltaic means or otherwise) in the most manageable way possible (say, in multiple small tanks) that it might serve as a continuous source of energy in a way very much akin to the more usual manners of continuous energy supply, such as battery banks, but rather more spartan and integrated.
 7  
 8  Admittedly, we have come at this problem somewhat backwards (the typical *solution in search of problem*, but applied very much unironically) and decided upon the system prior to any consideration of its application, and since that system would gravitate around compressed air, we are given directly to determine all of the various conversions involved or available thereto and thus arrive at perhaps the most narrow utility conceivable.  Indeed might we imagine even the heat of the compression process or the sapping of heat owed to the expansion of that air into its various duties as even proving of some utility if well managed by passive or otherwise mechanical means (likely an easier feat in small or partitioned spaces than large open ones, and we shall undoubtedly revisit this consideration).  In any case, beyond the specifics of climate control, all we are left with is the need for electricity (for powering sensors and automation) and pressure (for water and nutrient cycling as well as for oxygenation), and of these two, the latter should prove the most intensive, but also fortunately the most *direct* energy requirement of the entire system, despite the former having commanded the most consideration among the pioneers of MCAES.
 9  
10  Let us then simply illustrate in rough detail one possible template for designing such a system:
11  
12   * A solar panel coupled with an air-compressor, ideally suited to 100% duty-cycle. (a scroll air compressor, for instance)
13   * The solar/compressor assembly should include a low-power computer and a pneumatically powered generator of some sort. (air compressor used in reverse? turbine? flywheel?)
14   * A terrarium *master module* built off the back of the solar/compressor assembly with a sufficiently sized battery of receiver air tanks determined largely by the volume of plants contained therein.
15   * The receiver tanks being of optimal size to maximize output (small and numerous) and connected through solenoid valves to the solar/compressor.
16   * The aeroponic approach of watering/feeding/oxygenating through a microfog atomizer nozzle, controlled by its own solenoid.
17   * Additional terrarium modules, each with their own batteries of receiver tanks, connect to the "master" module which is fixed to the solar/compressor assembly and all receive air, power, and control (solenoid coordination, for instance) from that assembly, as well as each making its own relevant sensor data available thereto.
18   * Modules can also share air and water if necessary, passively in the latter case (probably merely a common reservoir in most cases where distance only accounts for a negligible inefficiencies in pressure) but possibly requiring fans and or controlled louvers in the former.
19   
20  To recap briefly the most relevant elements of this configuration, air expansion serves two purposes, one periodic and one intermittently based upon conditions of energy availability: the former consisting of the simultaneous watering, feeding, and oxygenization of plants through the pressurization of a single nozzle for each module; the latter consisting of the generation of electricity pneumatically to power various computerized duties shared across modules, to include the control of solenoid valves.  Such a system could well be tested in isolation from all other considerations using conventional sources of electricity in order to determine the optimal number of tanks to supply it for given lengths of time without power available to the air compressor.  This sort of testing should prove suitable to indicate the viability of this system in a given place and season, whether or not such needs should exceed feasibility (in terms of the volume of receiver tanks required and the ability of a single compressor to sufficiently fill those tanks), although in such cases, a higher ratio of "master modules" might suffice to mitigate this likelihood.  Alternatively, other or supplementary power sources could be utilized. (supplementing solar with wind or even hydro power in higher latitudes, for instance)
21        #+end_src
22        
23  *** resources
24  **** [[https://www.lowtechmagazine.com/2018/05/ditch-the-batteries-off-the-grid-compressed-air-energy-storage.html][Low-Tech Magazine]]
25  ** component candidates
26  *** [[https://axiomsafety.com/solar-powered-air-compressors/][Axiom Solar Air Compressor]]
27  
28      This seems to have most, if not all of the features desirable in this system; however the feasibility of this option is uncertain, given that the targeted market seems well outside of the scope of this application, and meaning that a more bootstrap approach may prove necessary.
29  
30      - Air Compressor Standard Duty:  100% Duty Cycle at 100psi and 72°F
31      - More than 3,600 hours running without any maintenance
32      - Modbus communication allows remote reporting of all events
33      - Microcontroller logs and stores system events
34      - 140 Watt Solar Panel (Expandable)
35      - Extended run time with two 110 Ah deep cycle batteries (Expandable)
36      - Operating Voltage:  12 vdc
37      - Power Source:  Photovoltaic (Typical).
38      - Controller - Battery Charger:  20 Amp Maximum Solar Array Current (Expandable)
39      - Controller - Compressor Drivers:  Independent control of up to two (2) air compressors
40  
41  ****  Options:
42       - Commercial AC power
43       - External 12vdc source
44       - Energy Storage:  12 vdc, sealed lead acid batteries (AH capacity to be determined by the application)
45  
46  *** [[https://aeroscience.info/microfog-atomizers-1/][Aeroscience Microfog Atomizers]]
47  
48      Given that this system should use its pressurized air-store directly wherever appropriate, an aeroponic atomizing nozzle poses one of the most intriguing applications of this concept.  Among the more esoteric benefits associated with the available nozzles' particular engineering, this approach to aeroponics also intrinsically delivers well-oxygenated irrigation.
49  
50      - pneumatic atomizing ventruri nozzle for aeroponic (fogponic) irrigation
51      - allows large enough droplet size for nutrient and microbe transmission (0-10 microns, 8 avg.)
52      - 0.75 CFM @ 40 PSI and 1.65 gallons per hour, respectively
53                 
54  **** Microfog Atomizer v.3 Flow Chart
55  | PSI |   CFM |  GPH |
56  |  60 | 0.875 | 1.76 |
57  |  55 | 0.850 | 1.72 |
58  |  50 | 0.800 | 1.70 |
59  |  45 | 0.775 | 1.68 |
60  |  40 | 0.750 | 1.65 |
61  |  35 | 0.700 | 1.81 |
62  |  30 | 0.675 | 2.11 |
63  |  25 | 0.650 | 2.38 |
64  |  20 | 0.600 | 2.51 |
65  |  15 | 0.550 | 2.73 |
66  |  10 | 0.500 | 2.64 |
67  
68  **** [[https://youtu.be/Y2LdTp5rsZQ][dry-fog explainer]]
69  **** [[https://youtu.be/-e_2celMVf8][nozzle overview]]
70  
71  *** [[https://g.co/kgs/51KE8b][solenoid valves]]
72  
73      These will be necessary in multiple stages within the system for the purpose of optimization, in both air storage and controlled air release.
74                
75      - it could be useful to have a solenoid valve that will open when the power drops below a certain threshold (the minimum required to keep it closed? Preferably at the point in which a UPS would switch on?), including total loss of power, in order to spin up the generator before the UPS drains completely
76  
77  **** CAES receiver tank optimization
78       https://krisdedecker.typepad.com/.a/6a00e0099229e888330223c84a8018200c-pi
79       [[ipfs://QmUqCtfpW9TkoAXwutajeJumfmEuHu4jQrajMfCXf6pQsk/6a00e0099229e888330223c84a8018200c-500wi]]
80       [[ipfs://QmVKWeMg35SereXSuWBK6Bos1zEFxv8cRNMdRKgcXkertR]] 
81       - computer controlled valves necessary to ensure maximal PSI with the addition of receiver tanks
82  **** application in aeroponic irrigation
83       - necessary for scheduled and controlled release of air
84  *** [[https://hackaday.com/2019/08/05/a-supercap-ups/][supercapacitor UPS]]
85  
86      Ideally, the system's controller (likely a Raspberry Pi) should be powered interchangeably by the system's solar panels or its pneumatic generator, and given that the controller should be the only component particularly sensitive to such switching, it should be the only one in need of a UPS solution.  Supercapacitors should be ideal, given that low-maintenance sustainability is the chief goal of the whole system.
87  
88  **** [[https://www.youtube.com/watch?v=GeSvErqdmIM][why supercapacitors?]] 
89  **** https://www.saveyourpi.com/
90  ** meta
91  *** DONE add entry on [[https://www.rapidexpedition.org/waypoint/][wayPoint]] under ./αg
92      CLOSED: [2021-06-30 Wed 06:24]
93  **** wayPoint entry: https://www.rapidexpedition.org/waypoint/aerocaes/