Saturday, 12 April 2014

Comcorp

Today, I visited the only "commercial" Aquaponics enterprise in Singapore. They only started a few months ago. That goes to show how little people have caught on to Aquaponics.

I suppose Singaporeans are too rich. So if you need vegetables and fruit, you just go buy it at the supermarket rather than growing your own.

Anyway, I hope they succeed. Although I think they have a difficult task ahead. The problem is if you want to supply to hotels and restaurants, you have to have a large varieties of offerings. And if you want to stick to a few varieties and sell them to wholesalers, you need a very large quantities of each to achieve the economies of scale.

Floating system with IBC.

Non-Aquaponics section.


Their fish tank is 1,800 litres but surprisingly very few tilapias. Some tanks have 20-50 mid-size fish. Some tanks has couple of hundreds fingerling. But with that tank size, I think they need more fish.

The conventional wisdom is 1 fish to every 10 litres of water in the fish tank. So that will work out to be 180 adult tilapias per tank. Probably need more if the fish is below 400g - 500g.








Some tomatoes:



They are growing mostly basil and mint. I think later they will add in more varieties of vegetables and herbs. But it's a good start, I think.



Happy Farming.

Aquaponics - Simple Set-up

Today I did a small Aquaponics set-up today just to show that what you may do. This is done in ONE DAY. So it is not so difficult.

If you look in the web, there are many other examples. You may copy those as well. As long as it works, who cares?

Initially I thought of having some major racking system but I didn't want a monstrous thing.

There were two consideration:

1) it has to take a lot of weight. (I couldn't find the right Hydrotons so I have to prepared to use gravel in my growbeds, that means the rack has to take a lot more weight.)

2) It has to be simple in design and do not take up a lot of space.

The solution is PVC pipes, at least that's what I think. Will still have to test it out. So follow this blog, and I will update my progress.

I bought a lot of PVC pipes (1 inch/25mm)... about 10 metres.

Then a lot of elbow and t-shape 3-way joints. In Singapore, most of the hardware stores only have these two, so I have to improvised.

A) Start with the base. I want the rack to be able to go above and over the tank. So, I measured the OD of the fish tank and made sure it can fit.



B) Add T-joints to prepare for the legs


I thought the base wold a simple one but I think it may not take the weight.


C) Then add the legs..


By this time, I think I have to add in more legs to support the weight, so I did some changes.


I added 2 more legs on each side just to be sure. So the rack finally looks like this.

After that, you have to glue the whole rack with PVC glue. I got this from local hardware shop. Do it in a very well ventilated space and do wear mask. This thing is super toxic.


You should leave the elbows at the top unglued so that your can make some minor adjustment for alignments.


With the 2 growbeds going on top. I would have to place some anti-slip pad between the PVC rack and the bottom of the growbeds so the the whole thing won't slide off.





Naturally, the fish tank will have to fit inside the rack. This is a small 128 litre container, or equivalent to 33 gallons.


The 2 growbeds is about 102 litres and fish tank together with the rack. So I will have a 2 GB to 1 FT ratio.

I will talk about the above ratios and the application of sump tank in another post.

Next I will install the Bell Siphon in the growbeds.

Ok, that's it. If you have any questions, please leave it in the comments section.

Happy Farming.

=============================================

Update (19April 2014):

1) I realised that I will need a sump tank so this set-up will not do. I will have to reconfigure.

2) As it turn out, this PVC type will end up as a prototype. I actually cut it up to harvest whatever PVC pipes that I can salvage.

My new set-up - just completed. You can read the details here: Aquaponics - Simple set-up, Part-2.






Wednesday, 9 April 2014

Off-Gird Solar Power Set-up - The Basics



Solar Panel:

The glass surface is impact resistant and allows maximum light transmission. Single crystalline solar cells are encapsulated and bonded to the glass in multiple layers of ethylene vinyl acetate (EVA) and laminated with a white Tedlar. Backing insuring long life in severe environmental conditions. Anodized aluminum tubular frames add strength and durability to the modules. Your solar panel should include pre-drilled mounting holes. The weather resistant junction box accommodates all wiring methods. Ideally the solar panels should carry a 20-year, 80% power output warranty.
Your supplier should have stock for solar panels from 0.5W to 100W. Common sizes include 4W, 10W, 15W, 20W, 45W, 55W, 78W, 80W, 100W. Your supplier should have the ability to customize other sizes.

Solar Charge Controller:



Solar PV Charge Controllers are a integral part of any solar system to prolong the life of batteries. They take the uncertain voltage from a solar panel and condition it to safely charge lead acid batteries. These solar PV charge controllers use pulse width modulation (PWM) or Maximum Point Power Tracking (MPPT) , and a 3 or 4 stages charging method, bulk, absorption, and float (maintenance) charge. They also protect the panels from energy backflow from the solar batteries after the sun goes down. Solar charge controllers are necessary to protect your PV investment.

What features to look for:


The most sophisticated of the charge controller has PWM regulation with integrated temperature compensation with a LCD display, programming- and safety functions.

The battery state of charge is clearly displayed with a bar chart, as well as energy flows from and to the battery and the load status (e.g. overload, load short circuit). The deep discharge protection function can be set up to three different modes: voltage controlled, SOC controlled or adaptive (fuzzy logic). Acoustic warnings are built in, and also a programmable nightlight function.


  •     Working voltage: 12V / 24V Autoselect
  •     Battery State-of-Charge display LCD Charge and discharge status display
  •     Programmable controls.safety functions
  •     Full solid-state safety protection & alarm 
  •     5 load disconnect algorithm options 
  •     Integrated temperature compensation 
  •     Covered wire terminals(16mm2 max) 
  •     Built-in nightlight function and data-logging 
  •     Optional CXM Remote Display

Remote Display:


Remote display is designed to display panel current, load current and battery voltage of your PV system; charging, overload, low voltage disconnect status too. Additional you can display several values of CXN's data logger of the past 7 days as Ah, SOC, Battery voltage (morning, evening). This provides you more detailed information of your PV system.
  •     Display panel current, load current, and battery voltage, Ah, SOC, etc
  •     Clear, readable 3-digit LCD Display and symbols
  •     Two push button to select displayed value
  •     DIN rail and wall mounting
Batteries:


These 3 types are all are all designed for alternative energy systems.

1.      Flooded Type: These are Lead acid batteries that have caps to add water. Many manufacturers make these types for Solar Energy use. Trojan, Surrette, and Deka are probably the most well known. They are reasonably priced and work well for many years. All flooded batteries release gas when charged and should not be used indoors. If installed in an enclosure, a venting system should be used to vent out the gases which can be explosive. 

2.     Gel Type: Not to be confused with maintenance free batteries, sealed gel batteries have no vents and will not release gas during the charging process like flooded batteries do. Venting is therefore not required and they can be used indoors. This is a big advantage because it allows the batteries to maintain a more constant temperature and perform better. 

3.     AGM Type: Absorbed Glass Mat batteries may be the best available for Solar Power use. A woven glass mat is used between the plates to hold the electrolyte. They are leak/spill proof, do not out gas when charging, and have superior performance. They have all the advantages of the sealed gel types and are higher quality, maintain voltage better, self discharge slower, and last longer. They are more expensive, but you usually get what you pay for. This type of battery used in airplanes, hospitals, and remote telephone/cell tower installations.

Solar Sine Wave Inverter:

A power inverter, or inverter, is an electronic device or circuitry that changes direct current (DC) to alternating current (AC). The input voltage, output voltage and frequency, and overall power handling, are dependent on the design of the specific device or circuitry.

A power inverter can be entirely electronic or may be a combination of mechanical effects (such as a rotary apparatus) and electronic circuitry. Static inverters do not use moving parts in the conversion process.

You can get one on eBay for about US$135.00 (Made in China)




Some specifications as your guide:

Grid inverter working conditions
The electrical utility grid must have current and voltage is 220V AC (190-260V)
Recommend use solar panels
18V/1200Wp
DC Maximum Input Power
Automatic Control
DC maximum voltage
VpvDC28.5VDC
DC voltage range
Vpv 10.5V~28VDC
Maximum input current
Automatic Control
AC output power
1000W
AC maximum output power
1100W
Anti-voltage protection
Fuse
AC standard voltage range
220V(190-260V)
AC frequency range
50Hz/60Hz(Automatic detection and adjust)
Output current total
harmonic distortion
THDIAC <3%
Phase
<1%
Islanding protection
VAC;F AC
Output short circuit protection
Fuse
Show
LED
Standby Power
<2W
Voltage at Pmax
>15.5VDC
Maximum output power factor
99%
DC to AC conversion efficiency
>88%
Ambient temperature range
-25 °C~60°C(skin temperature)
Temperature protection
>75°C(skin temperature)
Humidity
0~99%(Indoor Type Design)
Waterproof
Indoor Type Design
Electromagnetic Compatibility
EN61000-6-3:2007 EN61000-6-1:2007
Power System Disturbance
EN50178+EN62109-1+VDE0126-1-12
Grid detection
DIN VDE 1026 UL1741
Certifications
CE certificate

Installation:

There are cases where solar panels are installed in the shade or turned away from the sun. Other cases include connecting solar panels in the reverse polarity, casing serious damage to inverters and burn them up. Benefits of a solar system can be diminished by poor installations and site selection.
 
Your supplier should provide installation services for products purchased from them. They should know how to install stand alone systems / off grid, on grid, solar panels, solar cabling, charge controllers, inverters, solar batteries and other relevant solar accessories. On request, they should also be able to provide maintenance and checks for the systems.

Happy Farming.