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
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.
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1753 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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.
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1754 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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.
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1755 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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)
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1756 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1757 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1758 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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.
.
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1759 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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.
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1760 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1761 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1762 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1763 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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.
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1764 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1765 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1766 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1767 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1768 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1769 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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.
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1770 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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.
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1771 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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.
Benigno P. Legamia Jr.- DEVELOPMENT AND TESTING OF A MODIFIED 500 GPS SOLAR POWERED POND
AERATOR SYSTEM
1772 AMERICAN RESEARCH THOUGHTS- Volume 1 │ Issue 7 │2015
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.
Top Related