development and testing of a modified 500 gps solar powered pond aerator system

1751

AMERICAN RESEARCH THOUGHTS ISSN: 2392 – 876X Available online at: www.researchthoughts.us http://dx.doi.org/10.6084/m9.figshare.1425132

Volume 1 │ Issue 7 │ May 2015

Impact Factor: 2.0178 (UIF)

DEVELOPMENT AND TESTING OF A

MODIFIED 500 GPS SOLAR POWERED POND

AERATOR SYSTEM

Benigno P. Legamia Jr., Ph.D.

Don Honorio Ventura Technological State University

(DHVTSU) Main Campus, Bacolor, Pampanga, Philippines

Abstract: One of the problems of fish farming in ponds is the dissolved oxygen (DO) concentration

in water. Lack of dissolved oxygen from just a few feet below the surface of the pond causes fish to

swim on the water surface. Fish may die either from warm water where oxygen becomes less soluble at

higher temperature or from ammonia and carbon dioxide that turned into gas bubbles in their

bloodstream. The best way to control or eliminate the causes of fish kill is to ensure that there is

always enough oxygen in the pond. To minimize, if not to eradicate this problem, a study on the

development and pre-testing of a modified 500 gallons per hour Solar Powered Pond Aerator System

project also known as SPAS-500 was conducted. It is a self-contained unit that floats on the water and

provides consistent levels of oxygen using the venturi air ejector technology. It directly uses the

collected energy from the sun during daytime and the stored energy of the batteries at night time.

The method of the evaluation was based on the data gathered from the hydrological and electrical

application of the system. Varied methods of computations and testing as well as measuring

instruments/devices were utilized to achieve reliable results and significant conclusions. Finally, the

study showed that utilization of the SPAS-500 yielded a significant impact on economic and

environment. It means that the device can address the minimum aeration requirements needed by

small and medium size aquamarine businesses.

Key Words: Aerator, SPAS-500, Venturi, Fishkill, Air induction, Dissolved oxygen, Gas

bubbles

1. INTRODUCTION

In fish farming, the ability to maintain water quality is one of the vital concerns to

improve the production capacity and profitability of the enterprise. The conventional

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Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND

AERATOR SYSTEM

1752 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015

method used to maintain the quality of water is through efficient aeration system.

Aeration is the process of conveying water and air into close contact by exposing thin

drops of water onto the air or by producing small bubbles of air and letting them

upswing through the water. Aeration can remove certain dissolved gasses and minerals

through a process called oxidation. We can use the usual design of aerator which is

introducing air into water or water into the air. All aerators are designed to create a

better amount of contact between the air and water to increase the transfer of gasses. It

depends on the type we use, either driven by mechanical energy or electrical energy.

Various types of aeration, such as bubbler type, splashed type, and pump type can be

found in the field.

The cooler water has the capacity to hold more dissolved oxygen than warm

water. As water temperature increases, it holds less and less dissolved oxygen since

oxygen becomes less soluble at the higher water temperature. This increase in

temperature usually poses a serious problem for fish growers. Nevertheless, when high

temperature combined with little wind and high cloud cover, fish are trapped that often

result in massive fish kills. The lack of oxygen from just a few feet below the surface or

to the bottom of the pond may cause fish to swim on the water surface. In this manner,

fish may die either from warm water or from ammonia and carbon dioxide that turned

into gas bubbles in the bloodstream of the fish. Rotting weeds or algae, as a result of

using herbicides or algaecides, can also cause a temporary lack of oxygen. This can be

experienced in the middle of the night when plant photosynthesis reverses and

competes with the fish for oxygen. Another perennial problem is the sudden change in

water temperature that causes fish kill and poses a serious threat especially to the

aquamarine business, in particular, and to the Philippine economy, as a whole.

The best way to control (or even to eliminate) the causes of fish kills is to ensure

that there is always enough dissolved oxygen transfer in the pond. Based on the

geographical region, fish ponds are located away from power lines as in the case of

Barangay Kabahutan in Orani, Bataan, Philippines. This necessitates tapping the

potentials of the renewable type of energy such as solar. In the Philippines, the annual

average solar radiation is around 4.7 kWhr./m2/d with 9.2% monthly variation. The

solar energy is a clean type of renewable source which neither produces greenhouse

gasses nor releases hazardous wastes through its utilization. Renewable energy sources

are being widely used to address the global environmental issues.


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The researcher took part in heeding the call by developing a system using

renewable sources and tried to amplify a technology generated study on the fabrication

and conduction of testing and evaluation procedures for the modified five hundred

gallons per hour (500 GPH) and Solar Powered Aerator System project or better known

as SPAS-500.

The SPAS-500 system is a self-contained aerator unit that is ready to float on the

water surface and starts pumping. The aerator assembly (as shown in Figure 1) has five

main components: (1) the aerator’s main cradle or base, (2) solar panel assembly and

controller, (3) the dc aerator motor and pump (venturi type) assembly (4) the battery

bank system, and (5) electronic controller circuit assembly.

Figure 1: The modified solar powered pond aerator assembly

This aerator can provide consistent levels of oxygen at all times by using the latest

technology in the air ejector system. Fish are not stressed by a pre-summer or pre-rainy

season turnover. This eco-friendly aeration technology is the latest green technology

approach to a pond and similar water body aerating application. It is an entirely solar

powered system that provides at least 500 gallons of water per hour (500 GPH of water

flow) and 1 cubic feet per minute (CFM) of air induction. This nearly maintenance free

system will operate during daytime by using the directly collected energy from the sun,

through the solar panels, and will efficiently run the water pump through the stored

energy from the battery during night time. The specially designed water pump that

discharges through low-pressure nozzles will let air be mixed in turbid water resulting

in a higher dissolved oxygen transfer. In this manner, oxygen does not only keep fish

alive but also ensure the health of the entire ecosystem.


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Figure 2: The solar powered pond aerator floating on the demonstration pond

2. OBJECTIVES

Generally, the research aimed to develop and evaluate the operation and performance

of a modified solar powered pond aerator system. Specifically, the study aimed to: (a)

harness the solar energy potential to power-up a modified type of pond aerator, (2) to

invigorate the fish pond water condition by producing sufficient amount of oxygen by

using the Venturi tube type system, (3) examine the economic and environmental

impact of the project, and (4) contribute to sustainable technology generated project

development in the field of aquamarine business

3. FRAMEWORK

The conceptual model provides the general structure and guide in the development and

evaluation of the study, as presented in Figure 3.


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Figure 3: Conceptual Framework

The study was focused on the development of a modified solar powered pond aerator

using locally available indigenous materials and evaluation of its operation,

performance and impact. The evaluation results served as inputs to the study.

The researcher has conducted site evaluation, random interviews and testing

regarding the SPAS 500 device which served as basis for needs assessment. The results

of the tests and evaluation were tabulated and meticulously analyzed, which showed

that the project was efficient and reliable in terms of its performance and operation

especially during nighttime.

4. MATERIALS AND METHOD

On January 5, 2008, the Bureau of Fisheries and Aquatic Resources (BFAR) announced

that a fish kill at Taal Lake and other barangays such as Leviste, Balingkulong, Laurel,

Aya and Ambulong in Batangas, Philippines caused more than 50 metric tons or 3.25-

million pesos (US$1= ₱42.00) loss of cultured tilapia in just three days (January 2 to 4).

In Barangay Quiling in Talisay, more than 6 tons of maliputo fishes died and cost

INPUT

Analysis and evaluation

of the performance of the

different parameters of

the SPAS-500 after its

development in terms of:

Physical feature and

performance

Aeration Efficiency

Control design and

circuits

Electrical supply and

controls

Economic and

environmental benefits

PROCESS

Machine

Design and

Fabrication

Performance

Testing and

Evaluation

Observation

and interviews

Documentation

Data analysis

OUTPUT

Effective and

reliable 500

GPH- Solar

Powered

Pond Aerator

(SPAS 500)


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around ₱ 3,380,000.00 due to the high level of hydrogen sulfide and low dissolved

oxygen.

On May 30, 2011, the Bureau announced another fish kill of more than 850 metric

tons in Dagupan and Pangasinan, Philippines (as shown in Figure 4). According to the

scientists, the onset of the rainy season brought a sudden drop in the water

temperature, which lowered the oxygen levels in the lake that cause the death of fish.

Figure 4: The fish kill in Bolinao, Pangasinan, Philippines

In 2008, Republic Act 9513 was enacted or the Renewable Energy Utilization Act of 2008

and its declaration of policies are as follows, to wit:

(a) Accelerate the exploration, development and utilization of renewable energy resources to achieve

energy self-reliance, through the adoption of sustainable energy development strategies to reduce the

country’s dependence on fossil fuels in the operation of various equipment and thereby minimize the

country’s exposure to price fluctuations in the international markets of which cause the spiral down

effect to almost all business sectors and the national economy;

(b) Increase awareness in the utilization of renewable energy sources by institutionalizing the

development of national and local capabilities and promoting its efficient and cost-effective commercial

application by providing fiscal and non-fiscal incentives;

(c) Encourage the development and utilization of renewable energy resources as tools to effectively

prevent or reduce harmful emissions and thereby balance the goals of economic growth and

development with the protection of health and the environment; and

(d) Research and establish the necessary infrastructure, mechanism, appliances, tools and

equipment to carry out the mandates specified in this Act and other existing laws.

From the findings based on the study conducted by Williams (2009) on pond

water chemistry, he stressed that, it is not difficult to get all the air into the water that

the fish need. Oxygen is continually transferred into the water from the surface of the

pond and normally only a small waterfall will bring the pond water to or near to

saturation. Heavily populated ponds may need supplemental air and ponds with a lot


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of algae may need supplemental air at night when the plants are not making oxygen but

consuming it. It is very important that sufficient circulation is provided within the pond

so that all areas have proper oxygenation.

According to Stiegler (2008), the most significant way where dissolved oxygen is

introduced into the aquatic ecosystem is through the process of photosynthesis.

Likewise, additional oxygen is absorbed through water movement which acts to “stir”

the aquatic environment causing oxygen molecules in the air to dissolve into the water.

The more turbulent the water, the more dissolved oxygen is introduced. Oxygen is

depleted through wildlife respiration and the decomposition of organic material by

bacteria and fungi. Together, this system of oxygen production (photosynthesis) and

depletion (respiration) traverse an unsteady course of maintaining the proper amount

of dissolved oxygen throughout the entire ecosystem.

On the study conducted by Singian, A. B. et al. in 1999, he pointed out that there

were instances where institutional arrangements evolved to address the indivisibility

problem in producing imperative machinery and equipment thus allowing a wider

access to existing technologies. One of the most familiar cases in 1980s was the rental of

large pond aerators. This is a strong indication that in many instances, institutional

innovations occur to correct constraints such as indivisibility of physical capital, thus

allowing the benefits of this technology to accrue to more fish growers particularly

those that cannot afford to purchase lumpy capital equipment.

Based on the above-mentioned papers, the researcher continued the research on

renewable energy for small-scale application such as the portable pond aerator system

with minimum electrical power requirement and meets the demand of efficient aeration

process to mitigate fish kill.

5. ILLUSTRATIVE WORK FLOW REPRESENTATION

The study embarked on the design and development of a modified 500 GPH Solar

Powered Aerator System (SPAS-500). It was installed on the fishponds in Barangay

Kabahutan, Orani, and Bataan, Philippines for preliminary testing and evaluation of the

project and its system’s actual performance level. The gathered pre-tests data, results

and essential feedbacks on the different system parameters and considerations were

used in determining the needed modifications on the project. Considering the foregoing


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workflow, the operationalization of the different activities, concepts, and relationships,

this study was performed as shown in Figure 5.

Figure 5: Project illustrative workflow

6. PROGRAM STRATEGIES, MANAGEMENT, AND PROCESS

The functionality of the improved project facilities was dependent on the systematic

management practices of the end-users. The interconnectedness of all activities was

observed in accordance with the existing thrust of the Don Honorio Ventura

Technological State University (DHVTSU) and its stakeholders. The simple evaluation,

testing, and patenting workflow (as shown in Figure 6) was adopted in the

management aspect of the project by the researcher, collaborators, and production

personnel.

.


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Figure 6: The evaluation and testing process flow chart

7. POND AERATOR SYSTEM PLANNING

This stage determines the feasibility and viability of the proposed pond aerator system.

Some vital factors considered include the geographical location of the pond, volume of

pond water, water surface temperature, pond stocking capacity, required electrical

loads to be supplied by the solar panels and controls, and the project development cost.

8. AERATION INDUCTION ASPECTS

The Modified Solar Powered Aerator System (SPAS-500) is a self-contained unit that

can provide consistent levels of oxygen at all times by using the venturi technology (as

shown in figure 7) in the air ejector system. This eco-friendly aeration technology is a

green technology approach to the pond and similar water body aerating system. The

venturi tube is streamlined at both ends and equipped with annual rings around the

periphery inlet and throat. Piezometer rings were also used to permit controlled and

efficient purging of the pressure tap holes. The project provided at least five hundred

gallons of water per hour (500 GPH of water flow) and 1.25 Cubic Feet per Minute

(CFM) of air induction for 24 hours a day. In this manner, oxygen does not only keep

fish alive but also the health of the entire ecosystem.


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Figure 7: The 1- inch diameter venturi tube and flange used on the project

Another important consideration of the project was the specially designed water pump

that discharges through low-pressure nozzles and allowed the air being mixed in turbid

water resulting in a higher dissolved oxygen transfer.

9. THE ANALYSIS, COMPUTATIONS, AND PRE-TEST ACTIVITIES

The demonstration pond was used for crabs, prawns, and milkfish production with a

total area of ±10,500 square meters. The area was divided into 4 parts; 1 part for master

pond, and the remaining 3 parts as enlargement ponds. The location of fishpond is far

from the electric power lines so that the solar power generation system is used as an off-

grid system. All loads will be supplied by the solar power generation. The pond aerator

was concentrated to the 7,875 m² enlargement pond. The aeration is needed during

night time, due to the lowest point of oxygen in the air. The exterior lighting system

was installed to help the pond security at night. The lamps should provide enough

illumination for pond watchers to keep sound condition surrounding the pond. The

illumination of the lamp is about 1.5 foot-candle. The lighting system of the pond area is

divided into eight (8) major locations; one (1) spot in the control room, two (2) spot on

the master pond area, three (4) spots on the enlargement pond and one (1) spot to the

watchers quarter using 25 watts of compact fluorescent lamp (CFL)

The study was conducted in four 15-day phases. During the two phases, water

quality data were continuously recorded by various testing instruments which were

suspended one foot above the bed of each pond. A portable multi-parameter

physicochemical and organic meter tester (as shown in Figure 8) was used to record

measurements at one-foot intervals throughout the water column to determine the

dissolved oxygen levels at various depths and the presence of stratification. In addition

to the monitored data, water samples were collected from each of the ponds at the same

depth as the test prods and electrodes. The grab samples were laboratory analyzed for


AERATOR SYSTEM


pH, specific conductance, turbidity, ammonia nitrogen, total Kjeldahl nitrogen, total

phosphorus and chlorophyll content.

Figure 8: The portable multi-parameter physicochemical and organic meter tester (AquaTest

MO-Model P-103) used during the water testing.

A typical pond at a temperature of ±70° F. will have concentrations of about 13 mg/l

Nitrogen, 9 mg/l Oxygen, and 35 mg/l Carbon Dioxide. As the air components dissolve

into the water, a maximum point was reached where no more can be added. This point

is called saturation. The saturation points are different for each of the gasses and are

dependent upon several different factors, but the temperature is the most important. As

the temperature increases, the water simply cannot hold as much of each type of gas.

For oxygen, the approximate saturation level at 50° F. is 11.5 mg/l, at 70° F., 9 mg/l, and

at 90° F., 7.5 mg/l. (See Figure 8). Impurities added to the water (i.e. salt) further

decrease these saturation levels. At less than four kilograms of salt per hundred gallons

of water (5 ppt) will decrease the oxygen saturation levels of 1 mg/l.

Figure 9: Oxygen Saturation vs. Temperature


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10. LOAD CALCULATION OF FISH POND LOAD

System

Number

Type of

Utilization Load Power Working Time Demand Energy

1 Aeration System 187 watts

10 hours

7:00 PM-

5:00 AM

1,870 Wh/day

2 Interior Lightings 2 x 25 watts

6 hours

(Intermittent

Use)

300 Wh/day

3 Exterior Lightings 6 x 25 watts

10 hours

7:00 PM-

5:00 AM

1,500 Wh/day

TOTAL 3,670 Wh/day

Table 1 shows the energy demand of fish pond in Barangay Kabuhatan, Orion, Bataan,

Philippines

Calculating the overall system losses, assumed that the battery efficiency is at 90%,

inverter efficiency at 85% and wiring efficiency at 93%, with the total load calculated to

be 2.378 Wh. based on the equation below:

11. SYSTEM COMPONENTS

Solar Panels

The value of adaptation factor for the typical solar power generation’s installation is 1,1.

The proposed solar power modules capacity “Ps” is calculated as:

Where: E demand is the total load of the system and E sun is the solar insolation

(kWh/m2/d). The computed photovoltaic (PV) cost is $2,5/watt. Based on the Philippine


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existing local market, cost per solar module is ₱22,000 for 0.2 kW. The availability of PV

sizes varies from 0.2 kW; 0.4 kW; 0.6 kW; 0.8 kW and 1 kW. and PV module lifespan

was estimated at 20 years with the maintenance cost set at 1 % of the capital cost. As a

general rule of thumb, the total amps from the PV panels are sized between 10% and

20% of the total amp-hours (Ah) of the battery pack.

Figure 10: The solar panel assembly used for the pond aerator

Battery

Renewable energy systems contain batteries. It serves as an electric storage container.

The energy stored in the batteries can then be used directly to power dc loads or it can

be inverted to power loads. The battery consists of a reversible electrochemical cell and

has a high efficiency. The battery accumulation capacity is more than 50% and it can

carry out the loads for 2 days of autonomy. The accumulation factor should be adjusted

to the power needed. The battery storage capacity was calculated at 9.512 Wh. The

24Vdc of the batteries capacity was calculated at 280 Ah.

The project used deep cycle battery instead of an ordinary wet cell car battery for some

reasons such as:

- Deep cycle battery is designed to provide a steady amount of current over a long

period of time.

- It is designed to be deeply discharged for repetitive times. (which causes the

quick run-down of most ordinary wet cell car batteries)

- Capable of storing energy during night time, on cloudy and rainy days.

- AGM deep cycle batteries are generally considered to be "maintenance free"

because they are sealed and do not require water to be added.


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If the harnessed energy is not stored efficiently, there will be an irregular flow of

current in the distribution circuit system. This type of battery is also one of the most

expensive parts of solar power generation systems so they need to be well cared of.

Figure 11: The 140 amp-hour, 12 volt sealed type AGM series battery (Courtesy of Northern

Arizona Wind and Sun)

The System Controller

Unlike other types of generators, solar panels can be short-circuited or open circuited

without causing damage to them. Controllers contain a relay that opens the charging

circuit, terminating the charge at a pre-set high voltage and, once a pre-set low voltage

is reached, closes the circuit, allowing charging to continue. Charge controllers prevent

excessive overcharging of the batteries within a battery-based power system. A charge

controller is the device that goes between the solar array and the batteries and is sized

to the systems they protect by the short circuit array current and watts matched to the

battery voltage. Most common are 12, 24 and 48 volts. Because of cold temperatures and

the “edge of cloud effect”, irregular increased current levels are not uncommon. For

these and other reasons, the size of a controller’s amperage should be increased by a

minimum of twenty-five percent of the peak solar array current rounded up. The

researcher used the manufacturers’ string calculator to correctly size the right charge

controller for the installed batteries.

Sizing the Charge Controller

To get the total wattage of the solar array, the number of panels is multiplied by

number of watts. Dividing this total wattage by the voltage of the battery bank is to get

the plus 25% to allow for cold temperatures. In the case of the project, 4 sets x 250 watt

solar panels = 1,000 watts / 24V battery bank = 41.7 amps + 25% = 52.09 rounded up = 60


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amp controller. Note that solar charge controllers are rated and sized by the solar

panel array current and system voltage.

Figure 12: The main system controller assembly of the modified venture aerator

The Aerator Pump and Motor

The Mag-Drive Pump was modified with front mount adjustable venturi intake and air

fractionating impeller. Unique ceramic shaft air fractionating impeller was designed

and it includes 18" vinyl aerating tube with noise suppressing muffler. Re-washable and

reusable debris pre-filter was meticulously adapted in the intake chamber. It operates

on 24 volts direct current source. The magnetic drive pump can specifically use for fresh

or saltwater applications.

Figure 13: 12 volts, 550gph Supreme Mag-Drive 5 Aerator pump and motor with

venturi and fractionating impeller

Calculation of Water Aerator Power

In general, the feasibility of the proposed water aerator power system is based on the

following potential input and output power equations:

Pin = H x Q x g

Pout = H x Q x g x n


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Where:

Pin = input power g = gravity (9.81 m/ )

Pout = output power (water pump output) n = efficiency (85%)

H = head of intake pipe (meter)

Q = water intake flow rate (liter/second)

For Power Regulation System

Since we are dealing with solar powered system, a step-down switching voltage

regulator was needed, so TL2575 step-down switching voltage regulator was used

suitable for wide input voltage range of up to 60V and available in fixed output voltage

of up 6 volts, 12 volts, and 24 volts or an adjustable output version. The TL2575 and

TL2575HV have an integrated switch capable of delivering 10Ampers to 50 amperes of

load current with excellent line and load regulation. The 2N3055 transistor was installed

on the circuit board for power switching circuits, series and shunt regulators, output

stages, and high fidelity ampere requirement of the water pump.

IN OUT

350µF/ 50V

Figure 13: The schematic diagram of the secondary voltage and current regulation circuit

Secondary Voltage Regulator

A voltage regulator is an electrical regulator designed to automatically maintain a

constant voltage level. For regulating the solar power outputs, the LM7805 voltage

regulator was used. Such a regulator was a vital necessity to prevent the solar panels

from overcharging the storage battery. A voltage regulator kept the battery in a safe

operating range. It performed two functions:

- Protect the battery(s) from overcharging when the sun is at its strongest

- Protect the battery(s) from excessive discharge in bad weather


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Figure 14: The LM7805 circuit

Figure 15: The tabulated characteristics of the LM7805 regulator

Variable Loads

From the above computation, the power had maintained the desired output of water

pump. It was due to having an electronic load controller which protects the load from

having fluctuation of voltage. This matched the electrical power that was collected by

the solar panels to the electrical loads that were connected, and stopped the voltage

from changing as devices were switched on and off.

The reserve power energy in the storage battery’s loading system and more loads

could still be connected into the main system circuit.

Reserve Capacity = Battery Capacity – Maximum Demand

Daily Average Load = (Unit generated per day) / (24 hours)

(LM7805) Electrical Characteristics

Parameter Symbol Conditions MIN TYP MAX UNIT

Output Voltage Vo TJ= 25 °C 4.8 5.0 5.2 V

Line Regulation ΔVo VI = 7V to 25V TJ = 25 °C 3 100

mV VI = 8V to 12V TJ = 25 °C 1 50

Load Regulation ΔVo IO = 5mA to 1.5A, 25 °C 15 100

mV IO = 250mA to 750mA, 25 °C 5 50

Ripple Rejection RR VI = 8V to 18V, f=120Hz 62 78 dB

Output Noise Voltage VN F= 10Hz to 100Hz TJ = 25 °C 40 μV

Dropout Voltage VD TJ = 25 °C 2.0 V

Quiescent Current

TJ = 25 °C 4.2 8 mA

Quiescent Current Change ΔIQ VI = 7V to 25V, TJ = 25 °C 1.3

mA IO = 5mA to 1A, TJ = 25 °C 0.5


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Comparative performance of various aerator discharge nozzle

Particular Diffuser Fountain Venturi

Power Requirements 6-12 amps 6-14 amps 3.3 amps

Oxygen Transfer Eff. 3 1.2-2.0 1.2 2.0-3.3

Rated Depth 2.5 meters min. Surface 1 to 6 meters

Coverage Area ** 1/2 to 1 sq.m 1½ to 2 sq.m 4 sq.m

Figure 15: Comparative results of water charging and discharging test

The oxygen transfer efficiency (OTE) of a diffuser system is a function of its depth in the

ponds. Typically, an OTE of about 1.6% per meter of depth is found for fine bubble

diffusers in a pond setting. For a lagoon with three meters of depth, a transfer efficiency

of about 16% could be expected. This means that 16% of the air added to a depth of

three meters will actively be transferred into the water while 84% will be excess and will

just create bubbles to the surface of the pond.

12. RESULTS AND DISCUSSION

INDICATORS SPAS-500

Functionality

The Solar Powered Pond Aerator system is a self-contained and ecological

friendly portable fish pond aerator that floats on the water surface. It

produces a minimum of 500 gallons per hour of infused oxidized water.

Its aeration process improves the pond water quality The high-efficiency

solar power and low power high-pressure DC air compressor/pump set

and associated accessories can delivering at least 24% of oxygen to every

volume of air pumped into the pond. It runs on a regulated 24 volts, direct

current input power supply (±0.5 potential tolerance) The system does not

require AC power, uses no fuel and maintenance-free.

Usability

It can be simultaneously used as an alternative source of electrical energy

to light up interior and exterior lightings fixtures especially during the

night time of not exceeding 80% of its capacity rating. The project can be

used as a power backup system for cell phone and other small power

loadings. Because of its compactness and portability, it can be easily

transferred from one pond spot to another


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For the Socio-Economic Aspects

a. The Main Beneficiaries

This improved Solar Powered Aerator System will directly benefit the small to

medium scale fish growers especially those who are living in the lowland areas

and cannot afford to buy the expensive commercial type aerator system. It will be

efficient enough to lessen (if not to totally eradicate) incurring unwanted losses of

the commodity due to the fish kill. The stakeholder can save money due to non-

payment of monthly electrical bills for their pond aerator system.

b. Direct Benefits

The project will hire laborers in the conduct of this project specifically those that

entails in the fabrication, assembly and installation of the project. Involve laborers

will surely get the direct benefits of this project in its construction phase. During

the implementation phase of this project, there will also be laborers that will be

hired in the conduct of its operations. On the consumption side, there will be an

increase in the supply of these commodities which will somehow affect the prices

although the numbers may not be as significant at the national scale.

Great chances are evitable that there will be an additional development that

can be imparted through this technology aside from providing alternative energy

for effective livelihood activities. The project further created a sense of

Reliability

Aside from its unique feature of fast and easy deployment, the unit retains

its simple operation and promotes the complete supply of regulated

oxygen as required aeration processes. The user operator manual is

provided to guide and ensure the user of reliable operation of the system

to continuously supply (24/7) needed fish pond aeration and its secondary

load systems.

Performance

Based on “venturi effect principle”, the aerator’s nozzles infuse

significantly huge volume of air bubbles containing oxygen which is

dissolved at the bottom of the pond. The end-user may choose to operate

the system either by continuous or by periodic duty mode due to its

modular circuit controls. The fully automatic control systems were

designed to run the entire aerator system up to 20 hours per day under

standard operating conditions. The battery backup system allows them to

run like normal under less-than-optimal conditions. The entire aeration

system runs efficiently for both hot and cold climates. Piloting and alarm

system are also integrated into the system to give a signal of the status of

the aerator.


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involvement and advocacy on environmental stewardship and awareness among

the residents especially the marginalized people of the community.

c. Indirect/Other Benefits

With this improved machine facilities, there will be lots of families that will benefit

from this project considering the labor that will be used in the pre-implementation

and implementation phase. The government will also benefit from this project

considering the transaction costs involved in the project. Imagine the taxes that

will be generated if this project will be utilized from one area to the other.

d. Cost Recovery

Pond owners can overcome or more than equate the production and installation

costs of the project in just a short period due to an increased and healthy yield.

Due to almost zero amounts of monthly electric energy consumption and

maintenance.

e. Sustainable Development Benefits

1. Clean, better-quality, convenient, reliable and affordable (low cost)

pond aerator system.

2. Reliable pond aeration system for aquaculture opportunities.

3. Improved oxygenation cycle that keeps fish alive, it keeps the entire

ecosystem healthy.

4. Increased environmental awareness in caring for and preserving the

mother nature

5. Creation of new employment opportunities for marketing,

installation and maintenance of the unit.

13. SUMMARY AND CONCLUSION

After the completion and pre-testing of the Solar Powered Aerator System (SPAS-

500) project, the following descriptions and findings were attained:

By introducing fish into the pond, the pond owner has assumed the

responsibility for the care of the fishes. This includes not only feeding them but

also providing them with a healthy environment in which they can live and thrive.

Partial determination of maintaining the quality of pond water can be fatal for

fish.


AERATOR SYSTEM


It was known during the pre-testing period that oxygen is continually transferred

into the water from the surface of the pond and normally only a small waterfall

will bring the pond water to or near to saturation. Heavily populated ponds with a

lot of algae need supplemental air especially at night when the plants are not

making oxygen but consuming it. It is very important that sufficient circulation is

provided within the pond so that all areas have proper oxygenation. By doubling

the aeration process, will also double the generated amount of oxygen into the

water. The device simultaneously provide improved method of infused oxygen

mixture circulation into the pond water as compared to the common method of

providing additional oxygen to the water is through the use of a paddle wheel.

At this point, the solar powered aerator system is a good self- contained

floating aeration pond device and circulation systems that can provide horizontal

and vertical circulation with aeration of the water body through a special venturi

nozzle design. The project efficiently continues the operation for ten (12) hours

during night operation by using the stored power of the battery.

Maintenance of the solar powered aerator system is just easy and simple. It

can be done without the need for special tools. The unit has an expected lifespan

of 20 to 25 years which can be extended with regular repair and maintenance.

15. RECOMMENDATIONS

Before embarking on any aeration system project, it is essential to survey the

proposed site to calculate the actual size of water pump requirement of the pond.

Some vital factors to be considered are topographic and geographic condition of

the pond, the holding / stock capacity of the pond, water condition, water

temperature. The larger are the area of the pond, the more aerators are required.

Aside from oxygen monitoring, regular tests and evaluations on the pond

bed, water contaminants, and temperature condition must be done to ensure the

healthy water condition of the pond. Constant checking and maintenance work

will be required in this system otherwise the life of the equipment and its system

will be considerably reduced.


AERATOR SYSTEM


BIBLIOGRAPHY

1. Barden, R. H. (2010). Principles of Hydroscience, 2nd Georgia Edition,

Delmar Publisher

2. Celis, Noel (2011-05-30). "Philippines struggle under a mountain of dead fish".

AFP. Retrieved 2011-05-30.

3. Daniels, A.R. (2005). Introduction to Electrical Aeration Machines, Mac

Millan.

4. Stiegrel, O. (2008), Mitigating Fishkill through Proper Pond Oxygenation

and Management. 3rd Edtion

5. Luistro, M. A. (2008-01-05).Inquirer.net, "Taal Lake fishkill causes ₱3-M losses".

Philippine Daily Inquirer. Retrieved on 2011-01-15.

6. McDougal, L. (2009), Integrated Mathematics for Advance Studies, 4th

Edition, Houghton Mifflin Co.

7. Republic Act 9513 “The Renewable Energy Utilization Act of 2008.

8. Singian, A. B. et al. (2009). Feasibility Paper entitled: “Harnessing

Renewable Energy for Postharvest Facility Applications”.

9. Williams, E. B. (2009) Fundamentals of Pond Chemistry, 4th Edition,

Prentice Hill.