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Surname, Initial(s). (2012) Title of the thesis or dissertation. PhD. (Chemistry)/ M.Sc. (Physics)/
M.A. (Philosophy)/M.Com. (Finance) etc. [Unpublished]: University of Johannesburg. Retrieved
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ENERGY EFFICIENCY
CHARACTERISATION OF A SOLAR-
PHOTOVOLTAIC WATER PUMP SYSTEM
By
Degree
MASTERS INGENERIAE
in
at
the
UNIVERSITY OF JOHANNESBURG
SUPERVISOR:
DR. D.C. PENTZ
FEB 2015
ENERGY EFFICIENCY CHARACTERISATION OF A SOLAR-
PHOTOVOLTAIC WATER PUMP SYSTEM
ABSTRACT:
ENERGY EFFICIENCY CHARACTERISATION OF A SOLAR-
PHOTOVOLTAIC WATER PUMP
ACKNOWLEDGEMENTS:
The following acknowledgements have to be made in regard to this research study’s
completion:
Firstly I would like to acknowledge the guidance of my supervisor, Dr. D.C. Pentz,
and the assistance in acquiring financing for the required components to construct the
solar-PV water pumping experimental setup. In this regard I would also like to
acknowledge my research group, the Group on Electronic Energy Processing (GEEP),
and colleagues at GEEP for their inputs, guidance and intellectual contributions
towards completing this research study. Acknowledgement must extend to Professor
D. van Wyk for the guidance towards the study field and contributions of many years
of experience and knowledge. To my fellow post graduate colleagues Andrew
Joannou, Theren Lam and Eduard Basson for their contributions during discussions
and evaluation of existing content.
The University of Johannesburg (UJ), the Faculty of Engineering and the Built
Environment as well as the Department of Electrical and Electronic Engineering
Science (EEES) for the opportunity to pursue post graduate studies and for creating an
intellectual environment for undergraduate as well as post graduate students.
The financial assistance of the National Research Foundation (NRF) towards this
research is hereby acknowledged. Opinions expressed and conclusions arrived at, are
those of the author and are not necessarily to be attributed to the NRF.
I would also like to acknowledge Eddie van Dyk for his assistance in obtaining the
final sets of results with an actual solar-PV panel to verify the emulated results
obtained. Finally I would like to thank my friends, family and in particular Liezl Nell
for continuous support, encouragement and assistance where possible in the
completion of my post-graduate work.
Thean Hoogenboezem
November 2014
Table of Contents
Abstract: ................................................................................................................................................... i
Acknowledgements:................................................................................................................................ ii
List of Figures: ........................................................................................................................................ vi
List of Tables: ....................................................................................................................................... viii
List of Abbreviations: ............................................................................................................................. ix
1. PROBLEM STATEMENT .................................................................................................................... 1
1.1. Introduction and Context........................................................................................................ 1
1.2. Problem Statement ................................................................................................................. 2
1.3. Project Objectives ................................................................................................................... 2
1.4. Scope of Project ...................................................................................................................... 2
1.5. Methodology Overview .......................................................................................................... 3
1.6. Document Overview ............................................................................................................... 3
1.7. Chapter Summary ................................................................................................................... 4
2. LITERATURE REVIEW ....................................................................................................................... 5
2.1. Introduction ............................................................................................................................ 5
2.2. Applications............................................................................................................................. 5
2.3. Solar-PV water pumping system concepts ............................................................................. 6
2.3.1. Solar-PV Cell .................................................................................................................... 6
2.3.2. Solar Irradiation ............................................................................................................ 12
2.3.3. Solar Insulation ............................................................................................................. 13
2.3.4. Non-Battery-Assisted Operation ................................................................................... 14
2.3.5. Power versus Energy Efficiency (Performance Characterisation)................................. 14
2.3.6. System versus component efficiency............................................................................ 15
2.3.7. Propagation of experimental error: .............................................................................. 16
2.4. Components of the System ................................................................................................... 16
2.4.1. Solar-PV (Photovoltaic) Array ....................................................................................... 16
2.4.2. Converter/Inverter ........................................................................................................ 19
2.4.3. Motor/Pump Configuration .......................................................................................... 20
2.5. Literature investigation ......................................................................................................... 22
2.5.1. System Component Type Utilisation............................................................................. 22
2.5.2. Comparison of Completed Research ............................................................................ 26
LIST OF FIGURES:
Figure 2-1: Solar-PV Array with Basic Cell Structure Demonstrated ...................................... 6
Figure 2-2: Illustration of a Solar-PV Cell P-N Junction [4], [21] ........................................... 6
Figure 2-3: Side View Illustration of Solar-PV Cell and Conducting Current Path [4], [21] .. 7
Figure 2-4: Solar-PV Cell Equivalent Circuits, Voltage and Current Representations [4] ...... 7
Figure 2-5: Equivalent Circuit Diagrams of (A) Short-Circuit and (B) Open Circuit Test ...... 8
Figure 2-6: Plot of Ideal PV Cell under Two Different Levels of Solar Irradiance (25C) [4]
.................................................................................................................................................. 10
Figure 2-7: Solar-PV Equivalent Circuit Illustrating the Series, Parallel Resistances and the
Recombination Diode [4], [23] ................................................................................................ 11
Figure 2-8: Average Direct Nominal Irradiation (DNI) for a Daily Cycle ............................. 12
Figure 2-9: Block Diagram Illustrating the System while considering Encapsulation and
Internal Losses of a Solar-PV Cell/Panel/Array ..................................................................... 13
Figure 2-10: System versus Component Efficiencies............................................................... 15
Figure 2-11: Circuit Diagrams of the three Basic Converters (a) Boost- (b) Buck and (c)
Buck-Boost Converter Topologies ........................................................................................... 20
Figure 2-12: Block Diagrams of three Distinguishable Solar-PV Water Pumping Setups with
two Variations Each [26] ......................................................................................................... 24
Figure 3-1: Solar-PV Water Pumps (a) Franklin Electric, (b) ShurFlow, (c) Taifu TSQB2.0-
25-24/120, (d) 180 W Submersible Water Pump SP-JS3-1.8-60 (e) Lorentz PS150 Boost, (f)
Lorentz PS150C ....................................................................................................................... 36
Figure 3-2: Water Max DC150 Solar-PV water pumping solution......................................... 38
Figure 3-3: Graph of Solar Panel Internal Resistance (Ω) vs. Solar Irradiation (W/m2)....... 42
Figure 4-1: Final Proposed Experimental Setup..................................................................... 48
Figure 4-2 : Controlled Environment Experimental Setup...................................................... 49
Figure 4-3: Small Water Tank used for “Bucket Test” ........................................................... 50
Figure 5-1: Flow Rate versus Solar Irradiation ...................................................................... 53
Figure 5-2: Power Efficiency versus Solar Irradiation ........................................................... 54
Figure 5-3: Energy versus Time at Pumping Height 0m ......................................................... 56
Figure 5-4: Energy versus Time at Pumping Height 3.5m ...................................................... 57
Figure 5-5: Energy versus Time at Pumping Height 7m ......................................................... 57
Figure 5-6: Energy versus Time at Pumping Height 10.5m .................................................... 58
Figure 5-7: Energy versus Time at Pumping Height 14m ....................................................... 58
Figure 5-8: Power Efficiency versus Time from Emulated Results ......................................... 60
Figure 5-9: Power Efficiency versus Time for Actual Solar-PV panel ................................... 61
Figure A-1: Solar Irradiation for clear sky and actual operation for the daily annual average
............................................................................................................................................... - 3 -
Figure B-1: Water pump characterisation Flow Rate vs. incremental Solar Irradiation .... - 5 -
Figure B-2: Water pump characterisation Power Efficiency vs incremental Solar Irradiation -
5-
Figure B-3: Energy available, Energy input utilised and Energy Output of Water pump unit
at 0m discharge pressure ...................................................................................................... - 7 -
Figure B-4: Energy available, Energy input utilised and Energy Output of Water pump unit
at 3.5m discharge pressure ................................................................................................... - 7 -
Figure B-5: Energy available, Energy input utilised and Energy Output of Water pump unit
at 7m discharge pressure ...................................................................................................... - 8 -
Figure B-6: Energy available, Energy input utilised and Energy Output of Water pump unit
at 10.5m discharge pressure ................................................................................................. - 8 -
Figure B-7: Energy available, Energy input utilised and Energy Output of Water pump unit
at 14m discharge pressure .................................................................................................... - 9 -
Figure B-8: Power Efficiency plots for the five pumping heights over the daily operation
interval for the emulated case ............................................................................................... - 9 -
Figure B-9: Power efficiency plots of the five pumping heights for a morning operational
interval with an actual solar-PV panel ............................................................................... - 11 -
LIST OF TABLES:
Table 2-1: Comparison of Photovoltaic Cell Technologies
Table 2-8: Literature paper review and comparison of the work that has been done
Table 5-2: Summary of energy efficiencies at pumping heights with performance analysis
Table 5-3: Summary of Energy Efficiencies results obtained from the actual solar-PV panel test case
in comparison to the emulated energy efficiency results for the same pumping heights
LIST OF ABBREVIATIONS:
• PV – Photovoltaic
• GaAs – Gallium Arsenide
• CaTe – Cadmium Telluride
• Rpm – Revolutions per minute
• AC – Alternating Current
• DC – Direct Current
• SRM – Switched Reluctance Motor
• MPP – Maximum Power Point
• MPPT – Maximum Power Point Tracking
• CSP – Concentrated Solar Power
• DNIc – Clear Sky Direct Nominal Irradiation
• DNI – Direct Nominal Irradiation
1. PROBLEM STATEMENT
For solar-PV applications the important factors to consider are: cost effectiveness;
performance; reliability; maintainability and lifespan of the solar-PV system
components. The return on investment needs to be considered (which does not
only involve the financial cost thereof but also how much the system will benefit
the user and for what duration of time). This study will consider the field of solar-
PV water pumping systems for rural development to supply water to livestock.
The supply of water to livestock has been identified due to the fact that rural
African farmers do not have access to electricity from a grid. The rural
communities involved possess small herds of cattle and, therefore, farm on a
small scale.
Solar-PV water pumping systems already exist and are available for use in rural
development. The performance of the solar-PV water pumping systems are
important as the solar-PV panels only utilise a fraction of the available energy
from the solar irradiation, other system components must therefore utilise the
converted energy efficiently to make the usage of the system feasible. The
performance has to be measured in an effort to properly determine the actual
achieved efficiency of the system components. To understand the presently
characterised performances and performance indicators different methods have to
be considered and these different methods - to characterise the performance of a
solar-PV water pumping system - have to be compared. Present performance
indicators considered when analysing and comparing non-battery assisted solar-
PV water pumping systems are: power efficiency; flow rate and daily volume of
water supplied from the system. [2], [10], [12]–[16]. The first chapter of this
dissertation will define the problem and explain the project objectives; scope of
the project and research methodology.
The focus of this study will be the solar-PV water pumping application for the
supply of water to livestock. A small system rated at less than five hundred Watt
(500 W) of power will be utilised for experimental purposes. The experimental
The methodology that will be utilised throughout this study includes analysing
literature from different sources and researchers as well as considering the
different perspectives to critically understand the existing research in solar-PV
water pumping systems. From the above mentioned sources the weaknesses,
problems and future work of solar-PV water pumping systems may be identified
and investigated.
The chapter will then continue to identify possible component choices for the
controlled experimental environment and these components will be analysed and
compared. Components will be selected for the controlled experimental setup
based on the comparison and analyses. The layout, or structure, of the controlled
experimental environment setup will be formulated from the experimental
procedure which includes the identification of the measurements and the factors
effecting the measurements.
Once results have been obtained they will be analysed in an attempt to establish
whether the desired outcome of the experimental work has been achieved.
Thereafter the results will be compared to some performance indicator results and
based on the experimental choices to determine whether further results might be
required. In conclusion this research study will summarise what has been
achieved by the efficiency characterisation of a solar-PV water pump and identify
future work that may follow from it.
2. LITERATURE REVIEW
2.1. I NTRODUCTION
In the preceding chapter the topic of performance indicators, for non-battery
assisted solar-PV water pumping systems with non-constant input and output
conditions, has been identified. A brief introduction of the study field of solar-PV
water pumping systems has been done to present the technology and the purpose
of the technology being considered for the application of water pumping. The
performance of these systems is clearly important - due to the small amounts of
energy that are actually harvested from the sun. This energy has to be utilised
better by the system and the system has to be reliable, independent and well
suited to the application it was intended for to justify the usefulness of the system.
Supplying water to livestock is an important problem for rural farmers in many
parts of the world. In many of these rural areas no or little surface water is
available and underground water sources are frequently available. These
underground water sources are utilisable via conventional techniques such as
hand pumps which are however not capable of supplying sufficient volumes of
water to allow agricultural development.
Solar-PV technologies have been used in water pumping systems for the past two
decades and have been considered for a variety of different applications relating
to areas where no grid (or power lines) exists. The operation of these types of
systems poses many different design and implementation problems.
Environmental conditions largely influence the successful implementation of
these systems and therefore research and development should also be done to
improve their robustness. Solar-PV system considerations include the inherent
operational factors of the solar-PV panel. One of these factors is degradation
caused by operation at temperatures it was not designed for or the utilisation of
less expensive materials to manufacture the product.
2.2. A PPLICATIONS
The previously mentioned applications are a few of the general possibilities for
the use of solar-PV water pumping systems and, if implemented correctly, they
may improve the living standards of the rural communities. Due to the
environment and location these systems may frequently go unattended for long
periods of time and are required to remain operational in rural areas whilst a grid
is not available and water needs to be supplied.
Other applications that are worth mentioning are that of irrigation; supplying
water to small reservoirs for rural communities themselves; moving water from
central reservoirs or boreholes to water tanks (for any type of community using
A solar-PV cell has top and bottom electrical contacts used to capture the
electrons causing the electrical current flow from the solar-PV cell as
illustrated in Figure 2-3. The current, flowing in the opposite direction as the
electrons, inside the panel is caused by the electrons flow from the n-side
through the circuit to the p-side connector where the electrons recombine with
holes. Conventional current flow is defined as flowing in the opposite
direction of the electrons [4].
Figure 2-3: Side View Illustration of Solar-PV Cell and Conducting Current Path [4], [21]
Figure 2-4: Solar-PV Cell Equivalent Circuits, Voltage and Current Representations [4]
The main parameters utilised to model and characterise a solar-PV cell are
obtained by the short circuit test and the open circuit test illustrated in
Figure 2-5. The short circuit current ( ) parameter is obtained by shorting
together the terminals of the cell/panel as illustrated in Figure 2-5 (A),
causing the photon generated current originating from the cell to be the
short circuit current. And then to obtain the open circuit voltage ( )
parameter the terminals are left open and the voltage across these terminals
may be measured as illustrated in Figure 2-5 (B), this occurs since the
photon generated current is shunted internally by the p-n junction diode.
Figure 2-5: Equivalent Circuit Diagrams of (A) Short-Circuit and (B) Open Circuit Test
The current may be obtained utilising Kirchhoff’s current law (KCL) on the
equivalent circuit illustrated in Figure 2-4 in equation (2-1):
= − … (2-1)
Where:
Where:
There after by replacing the in equation (2-1) with equation (2-2) derives
the relationship of the solar-PV cell in equation (2-3):
= − ( − 1) … (2-3)
Where:
Therefore if the value of is known from the data sheet under standard test
(
conditions, ' = 1000 )* at an air mass of (AM) = 1.5, then the photon
generated current at any other irradiance, G (+/- ) and is given by:
.
. = (. ) . … (2-7)
/
Figure 2-6: Plot of Ideal PV Cell under Two Different Levels of Solar Irradiance (25 C) [4]
a) Series Resistance
In considering an actual solar-PV panel there are series connected solar-
PV cells that have series resistances. These resistances are present in the
current path through the semiconductor material, metal grid, contacts
and the current collecting bus. All these resistances are lumped together
as a single series resistance. The effect of this series resistance can have
a major effect on the operation in an actual solar-PV panel with long
arrays of series connected cells/modules because the value of resistance
is multiplied by the number of cells. The series resistance can be
represented by 01 [4], [23].
b) Parallel Resistance
The parallel resistance is also known as the “shunt resistance” as the
losses are associated with the small leakage of current flowing through a
resistive path in parallel with the intrinsic device. This resistance can be
represented as 02 and the effect is less severe than that of the series
resistance but becomes more noticeable with the use of multiple modules
in parallel for larger systems.
c) Recombination
Recombination is an effect experienced in the depletion region of solar-
PV cells providing non-ohmic current paths in parallel with intrinsic
solar-PV cells. As illustrated in Figure 2-7 the recombination effect can
be represented by a second diode (D2) in the equivalent circuit.
Figure 2-7: Solar-PV Equivalent Circuit Illustrating the Series, Parallel Resistances and the
Recombination Diode [4], [23]
The other variation of equation (2-8) where the first and second diodes
are combined can be rewritten as:
789:
?@#A:
= − [ 56 <
E; − 1] − ( ) … (2-9)
AB
Where:
However the illustration of Figure 2-7 and equations (2-8) and (2-9) do
not express all the factors that can be experienced by a solar-PV
cell/module/panel as the actual continuously changing effects of the
solar irradiation at different solar isolation levels is not expressed here.
Therefore the fluctuating nature of the solar irradiation’s effect on the
solar-PV cell cannot be properly expressed with this model. Different
solar insolation levels cause the solar irradiation absorbed by the solar-
PV cell to differ considerable throughout the daily operational cycle.
These solar isolation effects are due to factors such as the diffraction;
diffusion and absorption of light by the semiconductor material structure
and the effect the solar insulation layer has on the solar irradiation
entering the panel. The different intensities of light causing radiation
cannot all be absorbed: some are reflected and some pass through the
gratings of the material. This consideration is the motivation behind
multi junction solar-PV cells.
The following section will investigate solar irradiation data and propose
a different method for the modelling and possible emulation of a solar-
PV panel.
DNI - Actual
AVE DNI, DNIc vs. Time supplied solar
1.2 radiation
DNIc - Clear sky
solar radiation
1
Solar Irradiation (kW.m2)
0.8
0.6
0.4
0.2
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
Figure 2-8: Average Direct Nominal Irradiation (DNI) for a Daily Cycle
The average direct nominal irradiations (DNI) are plotted over a daily operational
cycle. There are two DNI plots illustrated in Figure 2-8 where the clear sky
(DNIc) represents the ideal DNI without any obstruction and the actual DNI the
expected DNI on the solar-PV panel. These obstructions include: overcast
weather; rain and any moisture in the air obstructing (reflecting and diffusing) the
intensity of the solar irradiation. For this study the DNI or the actual solar
irradiation will be utilised to consider the daily solar irradiation.
Figure 2-9: Block Diagram Illustrating the System while considering Encapsulation and
Internal Losses of a Solar-PV Cell/Panel/Array
Where:
The voltage source in Figure 2-9 represents the solar irradiation from the sun into
the solar-PV cells which have internal resistances changing based on the solar
irradiation experienced by the cells. These cells have output voltage and current
affected by the internal resistances of the cells. Equation (2-10) does not describe
Figure 2-9 but is a means of calculating the output power experienced in the
system and load.
For a system with an input-output voltage and current the power input and
output may be calculated by equations (2-11) and (2-12):
Energy is measured in Joule and is the product of both power and time.
Accordingly it can be used to indicate the performance of an operational
interval of a system. This constitutes a performance indicator for a system with
non-constant operational inputs and outputs.
From equation (2-14) the energy input and output intervals may be measured
and calculated by adding together the input as well as the output energies in
the pursuance of calculating the energy efficiency using equation (2-15).
w|{}
wxxyzy{|z}w|{} = w|{} × % … (2-15)
|
In Figure 2-10 the efficiency of the system may be calculated using the
following method, the two component efficiencies may be calculated using
equations (2-16) and (2-17):
w
wxx = w × % ... (2-16)
w
wxx = w × % ... (2-17)
w w w
wxx@ = w × % = 6 w < × 6 w < × % ... (2-18)
The combined efficiencies will be lower than the lowest efficiencies of the
separate components, due to the multiplication in equation (2-18).
If:
= ± ∆ … (2-19)
And:
= ± ∆ … (2-20)
Then the following error propagation can be utilised to calculate the total error
propagated with the measurements and calculations.
Addition:
= + , ∆ = ¡∆ + ∆ … (2-21)
Multiplication:
Dividing:
¥
= § = … (2-23)
New technologies exist which allow for solar-PV cells to be physically grown
(biomaterial cells) in a controlled environment. In order for these technologies
to be feasible for large scale industrial manufacturing innovations still have to
occur in the research field. Photovoltaic cell technologies may be utilised in
different applications according to cost versus quality, where quality is defined
by the efficiency, durability, life span, recyclability and manufacturability.
Table 2-1 does a comparison of the different photovoltaic cell technologies.
One very important factor which affects solar panels is degradation. Degrading
implies that certain solar-PV panels operating under extreme environmental
conditions may lose more than half of their efficiency to supply the rated
capacity within a year. Degrading occurs once certain solar-PV panels are
manufactured to operate for example: at a maximum of thirty degrees Celsius
but the actual operating temperature is forty to fifty degrees Celsius.
Degrading also occurs if the solar panel was manufactured from inexpensive
materials. Solar-PV panels made from better quality materials cause
degradation effects to be less severe under the same extreme environmental
conditions. The inherent problems experienced with solar-PV arrays, which
may affect the usage of the technology in certain applications, are
demonstrated in Table 2-2.
2.4.2. Converter/Inverter
When considering electronic energy processing a converter or inverter
topology needs to be designed, implemented and tested. Most applications
require a different converter or inverter to be designed according to the
specifications of the system and the requirements of the application. Two types
of energy processing systems exist: constituting converters, which converts
direct current (DC) to direct current whilst inverters convert direct current to
alternating current (AC) or vice versa.
Figure 2-11: Circuit Diagrams of the three Basic Converters (a) Buck- (b) Boost and
(c) Buck-Boost Converter Topologies
2.4.3.1. Motor
Many different motors may be considered for any specific application. The
two main distinguishable types are direct current (DC) and alternating
current (AC) motors. Direct current motors are larger in physical size than
alternating current motors of the same power rating [25].
also AC. Brushless motors have more complex driving circuitry. Brushless
motors are frequently considered as synchronous motors. The different AC
and DC motors are compared in Table 2-4, Table 2-5 and Table 2-6
respectfully herein below with specific regard to the important differences.
2.4.3.2. Pump
Table 2-7 compares different water pumps conducive to demonstrating the
different types of water pumps available relating to the application.
2.5.1.1. Introduction
From a performance analysis perspective the type of components used in an
experimental setup is important. When picking the type of components the
matching of these components and how the components are connected and
coupled to each other have a major role on the overall system efficiency.
The components chosen are required to match the operational specifications
of the system and other components of the system. Examples of these
specifications include: the power rating; voltage; current and rotational
speed requirements of the motor and pump that are coupled. The type of
electronic processing that is utilised to power the motor - which in turn
drives the water pump - influences the efficiency of energy transfer (being a
All these factors explain why the panel chosen has to be supplied with
specifications on: the lifecycle; expected degrading; the environmental
conditions the product is designed for; the materials used for manufacturing
and the product quality class (tested by a qualified and international
recognised standard or service provider such as to name but a few TUV
Rheinland, SGS consumer testing and services and CSA solar) [2].
Part of this analysis will focus on the type of performance indicator utilised,
the type of system as well as the recommendations made by the different
studies that have already been conducted. With regards to this research,
there is much insight to be gained when looking at how a better
performance indicator (such as the energy efficiency) may be utilised to
improve the performance indicator utilisation. Three main distinguishable
system types for solar-PV water pumping system considerations have been
of particular interest to previous authors: the case of permanent magnet DC
(PMDC); with and without a converter; and AC-induction motor. However
another case exists that has been used in the industrial market of solar-PV
water pumping systems.
The above illustrated cases have been characterised for various performance
based analyses. The main themes investigated by the authors for these test
cases are: software modelling simulations; performance analysis from
power efficiency; daily water supply measurements and calculations as well
as feasibility studies of the implementation of solar-PV water pumping
systems to rural communities and farming applications [2]–[7], [9], [12],
[15], [17]–[20], [26]–[48]. From these referenced cases it is clear that there
is a magnitude of literature relating to solar-PV water pumping system
performance; feasibility; improvement; design and characterisation over the
last two decades. Therefore the following key cases will be considered in
the discussion on the conclusions made from previous experimental work.
Another performance based comparison stated the same result that wind-
electric systems outperformed solar-PV water pumping systems at higher
power levels. This study analysed two wind-electric and two solar-PV water
pumping systems. The overall system performance of the two wind-electric
pumping systems (calculated as the water power over the wind power) were
7.5% and 9% respectively. The solar-PV cases, being a comparison of a
0.9kW AC and 0.1kW DC system (where the system efficiency was
calculated as the water power over the solar power), are of more interest to
this research study.
So:
These system power efficiencies are very low already, but are however
instantaneous efficiency results. Since the power can only be measured at
specific instant and the power efficiencies of the separate components used
here to calculate the efficiencies only relates to a single operational instant.
To get the system efficiency of a fluctuating system the overall energy
efficiency is required.
Table 2-8: Literature paper review and comparison of the work that has been done
Work/Author Application Panel/ Motor MPPT Pump System Problem Possible Solution
Generator Efficiency
Size
Modelling of Solar- Modelling of solar- Different AC & DC With and Centrifugal Power Power efficiency Calculate Energy
PV Water Pumping PV water pumping sizes, 350 without Efficiency, instant measured Efficiency
Systems – N.K. system W AC – 2.1%
Lujara DC – 7%
Performance Analysis Existing systems Solar-PV Solar-PV Solar-PV Solar-PV Solar-PV Better efficiency Energy Efficiency
of Wind-Electric and (1)Golden Photon (1)0.9 kW, (1)0.56 kW (1)Smart, (1) Centrifugal (1)Less than 1 % model, due to characterisation
Solar-PV Water 0.9kW (2)0.1 kW/ 1ΦAC, (2)24V (2) (2) Diaphragm (2)0.5 to 2.6 % multiple instants
Pumping Systems for (2)Solar Jack 0.1 Wind- DC/ Wind- Converter /Wind-Electric /Wind-Electric of power shown
Livestock Watering kW (3)Whisper Electric Electric (3)0.75 / Wind- (3)& (4) (3) & (4) on graphs. Energy
Applications – Brian 1000 Generator kW 3Φ AC, Electric Centrifugal Approx. 9% Efficiency still
D. Vick and R. Nolan (4)Bergey 1500, permanent (4)1.1kW 3Φ (3)&(4) better overall
Clark tested, Modelled magnet AC None characterisation
and Discussed (3)1.0 kW,
according to (4)1.5kW
performance and
Determining the Solar-PV material Different Motors not Not Positive Other efficiencies Power and Energy Energy Efficiency
optimal Solar Water analysis of sizes (110 discussed, specified, Displacement considered Efficiency not Characterisation
Pumping System for efficiency, to 660 rather different but (Diaphragm, considered and possible
Domestic Use, reliability and cost. Watts pumps believed to piston, helical) recommendations
Livestock watering or Controller systems) be used and centrifugal and possible
irrigation – Brian D. performance, solutions should
Vick and R. Nolan pump performance be suggested
Clark for applications
and matching
Solar Powered Water Analysed different Not DC – Discussed Centrifugal not Not discussed, Failures of current Choice of system,
Pumps: Problems, component specified Brushless, as a good seen as but good systems. matching of
pitfalls and Potential – technologies for Brushed, SRM option with desirable. performance said Component system
T.D. Short, M.A. solar PV water AC – Discussed controller/ Reciprocating to be required problems components and
Mueller pumping systems reliability vs. inverter Piston pump discussed. suggests topology
Cost of inverter systems suggested. to use.
ɸ - Phase
levels but at lower power levels very poor efficiencies exist which is caused by
either the efficiency of the pump or the motor at the rotational speeds.
The technologies available for the different system components were analysed
and summarised in tables (according to the system choices when deciding on the
design of the system). The advantages and disadvantages were identified and
discussed from different formulated perspectives and analysed accordingly. The
last section of this chapter consisted of ‘addressing’ each individual relevant
research paper in the interest of understanding the performance indicators and
characterisation of solar-PV water pumping systems. Other problems identified
by the authors of these research papers were also considered to understand other
possible problems identified within the field of solar-PV water pumping systems.
Certain problems identified have been addressed and possible solutions were
recommended. The two most pertinent factors of solar-PV water pumping
systems requiring further discussion are: the measurement of efficiency of system
performance and matching of system components.
The last section of this chapter consisted of discussing some of the findings and
conclusions of other authors and comparing the performance measures utilised.
These performance measures consisted of capacity analysis (the amount of water)
and power efficiency characterisation implemented with different methods and
comparisons of existing systems. The necessity of investigating a possible
improved or rather more accurate performance indicator has been identified.
Therefore investigating the formulation of energy efficiency characterisation as a
possible solution is evident.
The following chapters will focus on the motor and pump respectively i.e. a water
pumping unit as these components are believed to be the focal point of the
performance analysis in designing for the remainder of the components of a solar-
PV water pumping system. Different available motor and pump components will
be considered and a suitable system will be chosen based on the merit of a small
scale application (100 to 500 Watt) of supplying water to livestock.
3.2.5. Type
The type of system depends on the actual requirements - the pressure
(pumping head) as well as the amount of water required to be pumped. Other
important aspects include availability of the components as well as the shape,
robustness and manufacturability of the components. This research study does
not, however, focus on the type of system components due to the fact that the
goal of determining the energy efficiency will only, in time, is affected by the
abovementioned factors which cannot be fully controlled or measured in an
experimental setup.
3.2.6. Orientation
Orientation relates to the type of unit which, for example, includes both
surface mount and submersible borehole units. A submersible borehole unit
may be less likely to be stolen but cannot be easily maintained whereas a
surface mounted unit is more easily accessible and, therefore, maintain whilst
being subject to security and robustness issues. The capability of surface
mounted units is usually more ‘questionable’ than the pumping head provided
by submersible borehole units but this issue may be overcome with proper
system design to some extend (in the event of lower pumping heads).
Submersible borehole units may, in certain conditions, be a better option due
to depth/head specifications.
3.2.7. Maintainability
The maintainability of the components will not be analysed in the
experimental setup since it will not affect the energy efficiency measurements
during the time span of this experimental work.
3.2.8. Reliability
Reliability is not a factor affecting the experimental results as the system will
be installed in a controlled environment. Reliability and maintainability goes
hand in hand with the robustness of the chosen system components and is
always a design and system choice. Choosing components of a high quality
should address these factors to some extent. These factors will not, however,
be tested during the experimental work.
3.3.2. Pump
For this study the pump is the most important component to identify as it will
determine the choice of the other components in the system. Many different
types of water pumps exist that will offer sufficient performance in this
application. The most important factor, however, is that the pump selected
must be specified and designed for solar-PV applications. Since the water
pump chosen has to be able to pump sufficient volumes of water over a large
range of rotational speeds, operating at many different power levels. Based on
these factors the following water pump products have been identified as
possible options. Figure 3-1 illustrates the different pump options:
(a) (b)
(c) (d)
(e) (f)
Figure 3-1: Solar-PV Water Pumps (a) Franklin Electric, (b) ShurFlow, (c) Taifu TSQB2.0-
25-24/120, (d) 180 W Submersible Water Pump SP-JS3-1.8-60 (e) Lorentz PS150 Boost, (f)
Lorentz PS150C
Table 3-1 compares the different water pumps identified from Figure 3-1:
3.3.3. Motor
The choice of motor is inherently dependent on the choice of pump in the
application. Table 3-1 compares the different fixed unit pumps that are
considered for the experimental setup. From these different available options a
motor may be chosen. In previous studies the two main concerns were whether
to utilise a DC-motor directly connected to the solar-PV panel or alternatively
to use a motor with a converter (DC or AC).
A wide variety of options, which cover a broad range of users and sizes of
submersible solar-PV water pumping solutions, exist. A Water Max DC150
solar-PV water pumping system with all the required components can be
procured at a cost of approximately R35 000.
necessarily suitable since the actual application will be tied to a budget. Because a
bulk order will not be set for the chosen component it is difficult to analyse the
cost effectiveness of the chosen system components.
3.4.1.1. Motor
DC motors - or permanent magnet three phase synchronous motors -
experience fewer losses compared to the converter/inverter losses
experienced if DC power is converted to AC power. Table 3-1 compares a
variety of integrated motor and pump units. When analysing the available
solar-PV water pumps units with integrated motor and pumps, it became
clear that small power rated units (below 1 kW) are not readily available
with three phase induction motors. Therefore three phase induction motor
units do exist for large solar-PV water pumping applications and are
available in star and delta connections depending on the function as well as
design and supply voltage. A suitable three phase induction motor, within
the 100 to 500 Watt power range, could not be found for the purpose of this
study. Franklin Electric does supply solar-PV water pumping units with
single phase induction motors which range from 1.1 kW and higher. The
power rating of these induction motors, forming part of the water pumping
units, yet again exceeds the power rating considered in this research study.
The units that were identified in Table 3-1 are borehole units not designed
for solar-PV water pumping applications, the power fluctuations
experienced by solar-PV water pumps would surely either damage or not
work well with standard borehole motors.
In the event that a directly coupled DC motor is preferred, the water pump
units supplied by Shurflo can be considered. The Shurflo unit did not match
the desired operational specifications for the experimental setup. The water
pumping units supplied by Lorentz cover high-end applications the costs of
which are not necessarily suitable for this research study. Since these water
pumps exceed the available budget for the procurement of an experimental
solar-PV water pumping system. Taifu supplies water pumping units
utilising three phase synchronous motors at a reasonable price. The units
supplied are simplistic; robust; reliable and affordable. The Taifu 120 W
solar-PV water pump is the component of choice for a small solar-PV water
pumping application. These units match the available budget for the
procurement of an experimental solar-PV water pumping system and a
second hand unit is readily available. Table 3-2 compares the factors
considered in deciding on the best unit suited for the application.
Component Motor Type Power Voltage For Solar-PV Price Range Controller
(Three-Phase, AC Rating (Depending applications (Low Included
or DC) (<500 W) on Type) (<R5000.00)
, Medium
(<R10000),
High
(R10000<))
(a) Franklin Single Phase AC 230 W, 230 V or No, Borehole Low No
Electric 370 W and 380 V powered
Bore Hole 560 W applications
Pumps
(b) DC 120 W 12 V Yes Low N/A, Maybe
Shurflo: require MPPT
Premium
Demand 2088-
313-145
(c) Three phase 120 W 24 V Yes Low/ Yes
Taifu TSQB2.0- synchronous motor Medium
25-24/120 Solar
Booster Pump
(d) 180 W Three phase 180 W 24 V Yes Medium Yes
Submersible synchronous motor
water pump SP-
JS3-1.8-60
(e) Brushless DC 150 W 12-24 V Yes High Yes
Lorentz PS150
Boost
(f) Brushless DC 150 W 12-24 V Yes High Yes
Lorenz
PS150C
3.4.1.2. Pump
Table 3-3 compares the available units to choose a fixed water pump unit.
The pumping height of the chosen water pump unit is at an acceptable
height such as 10 to 20 meters. An important consideration as set out in
Table 3-2 is the price range of the water pumping units. The price of the
unit should fit the budget for the procurement of an experimental solar-PV
water pumping system, while still procuring a quality component. The
discharge pressure and flow rate of certain of the submersible water pump
units as listed in Table 3-3 complies with certain of the requirements of the
experimental setup.
according to the solar irradiation data obtained from the JRE as demonstrated
in Figure 2-8 and attached in Appendix A.b.i. The identified solar-PV panel
data from the data sheet is demonstrated in Table 3-5. A polynomial fit
according to the supplied internal resistance data of the solar-PV panel at
specific solar irradiations is illustrated in Figure 3-3, this polynomial fit
describes an exponentially decreasing internal resistance as the solar
irradiation increases. This result is expected and therefore the illustrated fit is a
good fit for the internal resistances of the solar-PV panel.
Power 150 W
Short-Circuit Current(z ) 8.71 A
Open-Circuit Voltage(ÊË ) 21.8 V
Module Efficiency 15.13 %
Rint
10
R_Int_Curve_Fit
8
6 Poly. (Rint)
4
2
0
0 200 400 600 800 1000 1200
Solar Irradiation (W.m2)
Figure 3-3: Graph of Solar Panel Internal Resistance (Ω) vs. Solar Irradiation (W/m2)
3.5.2. Converter/Inverter
It is evident from Table 3-2 and Table 3-3 that the components designed for
solar-PV applications will provide the best solutions for the specific
application and in the experimental setup. It is also evident that a three phase
synchronous motor with a centrifugal pump will offer the best solution in the
experimental setup. The Taifu water pumping unit specified in Table 3-2 and
Table 3-3 as (c) offers the desired specifications to match the experimental
setup requirements. The choice of existing matched components has been
made since loose components designed for solar-PV water pumping
applications at the rated power level are not readily available. However the
fact that it is a surface mounted unit will require additional design
considerations when setting up the experimental setup.
experimental tests will be explained and the results will be analysed to present
correctly measured and calculated energy efficiency measures of the solar-PV
water pump, motor and converter.
4. EXPERIMENTAL SETUP
4.1. I NTRODUCTION
In the previous chapters the different concepts and sections in the field of
solar-PV water pumping studies have been identified. Relevant research
papers were analysed in an attempt to identify the sections of the study field
which may be improved upon or which have not been previously considered.
The energy efficiency characterisation has, thus far, been identified as the
areas within the solar-PV water pumping field which require additional
attention. The previous chapter identified potential components to be utilised
in the experimental setup. These components have been analysed and the best
possible components have been chosen to be used in the experimental setup.
Components being the water pump unit consisting of a motor; pump and
converter containing a controller, the other components such as the water tank;
valve; pressure gauge and pipes will be fitted to the experimental setup with
the chosen water pump unit. The solar-PV panel will be emulated according to
the datasheet specifications of the solar-PV panel. In the chapter to follow the
experimental setup will be proposed and the required measurements thereof
will be discussed in detail. The Taifu water pump unit has been selected based
upon the analysis of the components discussed in the previous chapter. The
balance of the components required in the experimental setup will be chosen in
accordance with the water pump unit and the experimental setup will be
designed around the operation thereof.
4.2.1. Measurements
The water pump unit chosen in Chapter 3 has a three phase synchronous
permanent magnet motor and a converter which is supplied with the water
pump. Thus the input power to the converter is DC and the output power
from the converter is three-phase. Due to some harmonics in the voltage
and current waveforms, output frequency and continuous control signal
adjustments to the output of the converter less accurate measurements are
expected at the voltage and current levels. The interest and focus of the
experimental work is to characterise the energy efficiency of the solar-PV
water pumping unit, therefore the input to the converter will be measured.
The input voltage and current to the converter, being DC, may be used to
calculate input power. To calculate the input power equation (4-1) may be
used:
• IC – Input to Converter
The output energy of the pump may be calculated from the measured output
power for the various operational conditions. Equation (4-3) is utilised to
calculate the output power.
~{~Ì = Í ∗ Î ∗ ∗ Ï … (4-3)
Where:
The energy output of the pump may be calculated in the same fashion as the
energy input by utilising equation (4-4).
w|{}~Ì
= ~{~Ì
× … (4-4)
The energy efficieny of the water pump unit and the converter may be
calculated utilising equation (4-2) and (4-4) by inserting the results thereof
into equation (4-5).
w|{}~Ì
w|{} wxxyzy{|z}Ë|@{
Ì
= w|{} × %
Ë
… (4-5)
w|{} wxxyz{|z}Ò/~Ì
/Ë|{{ =
w|{}Ò/~Ì
/Ë|{{
w|{} × % … (4-6)
|Ò/~Ì
/Ë|{{
It is evident from equations (4-1) to (4-6) that the following variables are
required in the calculations:
Due to the fact that the Taifu water pump unit is supplied as motor, pump
and converter combined the combined energy efficiency characterisation is
an acceptable result of the experimental work on this research study.
Using the variables listed above the following additional variables has to be
calculated:
irradiation; causing a specific power input; and the water pump output
discharge pressure. As previously mentioned the solar-PV panel will be
emulated by utilising a power supply and resistance connected in series. The
input power level will be adjusted to emulate the different solar isolation
levels. The characterisation results will be utilised to measure the flow rates
obtained at the different power inputs and at the different discharge pressures
of operation. The results obtained may be utilised to calculate the energy
efficiency of the entire cycle of operation.
The illustration in Figure 4-1 has a power supply with a variable resistor, to
emulate the operation of a solar-PV panel, for reproducibility of the results.
The bus capacitor is utilised to prevent sudden changes in the voltage supplied
to the converter. Water is pumped from and into a single water tank to
maintain the same pressure level. The pressure gauge and valve are used to
maintain discharge pressures representing depths or heights of the pump. The
flow rate will then be measured with the bucket test.
• A – Power Supply
• B – Series Connected Resistor, used to emulate solar-PV panel internal
resistances
• C – Ammeter and Voltmeter
• D – Stabilising Bus Capacitor
B C
A E
D
The container as shown in Figure 4-3 has been marked in 1 litre increments up
to 15 litres. The container will float on the water surface in the water tank as
demonstrated in Figure 4-2. This will be done to maintain a constant water
level and input pressure when circulating water through the pump into the
container. The container remained upright during the experimental procedure
with the outlet pipe fixed within the containers top inlet.
Water
container
marked in 1
litre
increments
up to 15
litres.
By utilising the characterisation curves and data obtained the actual energy
efficiency may be calculated for the different discharge pressures. The
reasoning behind utilising different discharge pressures is due to the fact
that the system’s best operational specifications will demonstrate the
operational cycle of the water pump unit. The solar irradiation data
contained in Figure 2-8 read with the internal resistance data contained in
Figure 3-3 allows for the internal losses of the solar-PV panel to be
modelled. These losses will be subtracted from the corresponding solar
irradiation, in turn allowing the calculation of the input power to the
converter. The input power at the different time intervals during the course
of a day may be emulated to obtain the characterisation of the solar-PV
water pump unit. The output flow rates may then be measured and plotted
according to the input power levels. From the results obtained both the
input and output energy can be determined and utilised to calculate the
energy efficiency. The equations listed earlier in this chapter may be used.
A comparison of solar-PV water pumps were considered and analysed for the
purpose of choosing the best experimental setup to evaluate the energy
efficiency of a solar-PV water pump. A controlled experimental composition
has been suggested with the chosen solar-PV water pump to conduct the
experimental analysis. Taking into account the equations of energy efficiency
the required measurements on the experimental composition identified the
measurement equipment required. The approach to evaluating the
experimental setup has also been disclosed. In this chapter, the results obtained
from the experiment will be discussed and analysed with regards to the
characteristics of the elected solar-PV water pump. The energy efficiency
results of the water pump unit will be discussed as well as the operation
thereof at different pumping heights (discharge pressures). Before conclusions
can be drawn another set of results obtained with an actual solar-PV panel will
be analysed accordingly to establish the accuracy of the existing emulated
solar-PV panel results. These results have only been measured for a short
interval. The main purpose of this research study is to measure and calculate
the energy efficiency of a specific solar-PV water pump.
solar panel was at its highest level. The resistance was decreased in favour of
achieving the required solar irradiation or power levels and the output flow
rate was measured for each of these conditions. The input and output power
levels are measured to calculate the power efficiency under different operating
conditions.
Figure 5-1 presents a set of constructed graphs of the flow rates as a function
of solar irradiation, at different pumping heights. The graphs demonstrate that
the flow rate rapidly decreases as the pumping pressure is increased. At the
same time, as expected, the flow rate increases with an increase in solar
irradiation. For each respective pumping height there is a maximum
operational flow rate, pointed out on the plots in Figure 5-1, where the flow
rate remains constant irrespective of whether the available power is increased.
The operational limit with respect to the flow rate is reached when the pump’s
maximum output flow rate for the respective pumping height is reached. It
should be noted from the graphs for 14m and 17.5m the maximum flow rate
only occurs at higher power levels not present in this set of plots.
0.00035 14m
0.0003
17.5m
0.00025
0.0002
0.00015
0.0001
0.00005
0
0 100 200 300 400 500 600 700 800 900 1000
Solar Irradiation (W/m2)
to the fact that the system is not performing any work as is evident from
equation (4-3). At a 0m (A) pumping height the system does not perform any
displacement and therefore if there is a measurable input power, most of it is
losses. At 3.5 m (B) pumping height the power efficiency increases over 0m
(A) but also remains constant throughout the power range which is similar to
what is experienced at 0m (A) pumping height. However the flow rate does
not remain constant throughout for pumping heights of 0m and 3.5m as is
plotted in Figure 5-1.
30
3.5m
25
7m
20
15 10.5m
A_0m
10 14m
F_17.5m
5 17.5m
0
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
850
900
950
1000
The calculation of the energy efficiency requires the energy input and energy
output for all the time intervals of the daily operational cycle of the water
pump unit. The input voltage and current have been measured and used to
calculate the input power. The output flow rate was calculated at each interval
by measuring the time duration for each interval to pump 15 litres of water.
The flow rate calculated was employed with the pumping height to calculate
the output power. The time interval measured for pumping 15 litres of water
has been put to use to calculate the input and output energy of the water pump
unit for each interval. These results are plotted in graphs Figure 5-3, Figure
Thean Hoogenboezem Page 55
CHAPTER 5: EXPERIMENTAL SYSTEM CHARACTERISATION
5-4, Figure 5-5, Figure 5-6 and Figure 5-7 for the pumping heights of 0, 3.5, 7,
10.5 and 14m. It should be noted that the solar irradiation levels required to
pump water at a 17.5m height are not achievable with the solar irradiation
available from Figure 2-8 and therefore the energy efficiency has not been
calculated or listed in the sets of results.
Each of these plots contains the energy available from the solar irradiation
with the chosen solar panel in section 3.3.1. Accordingly the actual energy
input achieved by the water pump unit for the specific time interval and
pumping height. The energy output at the corresponding time intervals are also
present in the five graphs of the pumping heights.
60
50
40
30
20
10
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
The water pump unit does not fully exploit the available solar energy from the
solar-PV panel. This is due to the water pump not requiring more energy to
perform the work that is required for a 0m pumping height. The expected
result of a very low energy output is evident in the same graph.
60
50
40
30
20
10
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
60
50
40
30
20
10
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
60
50
40
30
20
10
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
From Figure 5-4, Figure 5-5, Figure 5-6 the following observations can be
made,
The consumed input and output energy increases as the pumping height
increases, as is expected since more work has to be done. The water pump unit
only achieves its maximum operational capability at higher power input levels.
100
Energy vs. Time
Energy Avaiable
90
Energy_Input_14m
80
Energy_Output_14m
70
Energy (kJ)
60
50
40
30
20
10
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
The output energy starts decreasing although the input energy still increases
with the pumping height. This observation confirms that somewhere between
7m, 10.5m and 14m the optimum operational pumping height was achieved.
In the following Table 5-2 the overall energy efficiencies have been calculated
for each pumping height. According to equation (2-15) the summation of the
output energy values divided by the sum of the input energy values multiplied
by a hundred percent provides the energy efficiency. Each associated pumping
height summarises the performance considerations relating to that energy
efficiency.
Table 5-2: Summary of energy efficiencies at pumping heights with performance analysis
between the input and output pipes. Therefore the conclusion can be drawn
that the useful power is equal to zero and the input power gets dissipated in the
losses, constituting almost zero efficiency.
Power_Efficiency_0m
Power Efficiency vs. Time
Power_Efficiency_3.5m
40
Power_Efficiency_7m
35
Power_Efficiency_10.5m
30
Power Efficiency (%)
Power_Efficiency_14m
25
20
15
10
Time (HH:MM)
emulated solar irradiation was also based on an average solar irradiation. The
power efficiency plots of these results are illustrated in Figure 5-9 which
contains similar operational characteristics to Figure 5-8 for a morning
operational cycle. These results are a frame of reference to add onto the
emulated solar PV case obtained by the solar irradiation data. A comparison of
the two sets of results allows the following observation that the operational
pattern is similar for pumping heights of 0, 3.5, 7 and 10.5 m. The pattern
obtained at 14 m is similar, but performs better under the actual solar-PV
condition indicating that the MPPT performs better with an actual solar-PV
panel to supply more accurate operational curves.
30
Power_Efficiency_10.5m
25
20 Power_Efficiency_14m
15
10
5
0
Time (HH:MM:SS)
Figure 5-9: Power Efficiency versus Time for Actual Solar-PV panel
Table 5-3 presents the energy efficiency results obtained for the actual solar-
PV panel, calculated in the same manner as the emulated results. Here, based
on the actual solar-PV panel calculated results, it is possible to note that the
emulated results are corresponding with the actual results case. Not only in
magnitude but the whole characteristic curve for a morning to early afternoon
corresponds with the obtained emulated solar-PV panel curves as illustrated in
Figure 5-8.
Table 5-3: Summary of Energy Efficiencies results obtained from the actual solar-PV panel test case
in comparison to the emulated energy efficiency results for the same pumping heights
When analysing the operational cycle of the solar-PV water pump unit it
became evident that it performs better under load, as is expected from most
electrical/mechanical systems. The water pump unit’s maximum practical
limits have been established for each of the five pumping heights. When
analysing the data measurements of the complete operational cycle per
pumping height the performance could be compared according to the flow
rate, energy efficiency and work performed. It has been established that
between 7 and 14 meters the optimal practical energy efficiency is exceeded.
Therefore at higher pumping heights the limits of the pump at lower power
levels drastically influences the functional performance.
The plotted power efficiencies from Figure 5-8 demonstrate the achievable
operational characteristics of the water pump unit using solar-PV panel data.
The plots demonstrate how the pumping height and solar irradiation affect the
operational power efficiency achieved by the water pump unit. Another
interesting observation is the decreased daily time interval that the water pump
unit actually pumps water at higher pumping heights.
In the pursuance of validating the power efficiency plots and energy efficiency
results obtained from the solar irradiation data a set of results has also been
obtained performing the same experiment with an actual solar-PV panel. Using
the results it was established that the practical operational characteristics
present in Figure 5-8 are also present in Figure 5-9. The calculated energy
efficiency results from the experiment with the actual solar-PV panel yielded
more or less the same result as obtained to the results obtained with the
emulated case. The exception was that at higher pumping heights the water
pump unit with an actual solar-PV panel performs better than the emulated
case. This can be due to the incorrect modelling of the panel resistances or
merely better water pump operation with an actual solar-PV panel.
A note on the experimental setup in Figure 4-2, the power supply and resistor
connected in between was used to emulate the VI curve of the solar-PV panel
chosen in section 3.5.1 with the solar irradiation data from appendix A.b
plotted in Figure 2-8. The resistor was adjusted according to the data and the
input voltage and current was measured and monitored for each desired
operational level. The results obtained for the emulated case combined with
the results obtained for the actual case dictate the accuracy and validity of the
experimental setup and method of performing the experiment.
6. CONCLUSION
6.1. I NTRODUCTION
Past research on Solar-PV water pumping were identified, analysed and
compared to the objectives of this research study. This was done in an attempt
to elaborate on research that has not yet been fully conducted. The two main
aspects which have been identified as possible topics to investigate are:
performance indicators and component choice considerations. The
performance indicators applied to date are unable to properly characterise and
portray the function of a system with non-constant operational conditions such
as found in pumping systems operating without batteries. The scale of the
water pumping system is important due to the fact that larger scale systems
would be superfluous in a rural community. Therefore smaller scale systems
constituting an operational range of in-between 100 to 500 Watt was focussed
on.
The solar-PV water pump unit elected from section 3.4 is not supplied with an
efficiency rating. This could indicate that the manufacturer is aware that power
efficiency does not accurately reflect the performance achievable by the solar-
PV water pump unit.
The energy efficiency figure obtained for each pumping height is a more
accurate representation of the performance of the water pump unit with the
operating conditions in question. Assuming we are comparing the possible
power efficiencies within each pumping height we can confirm that comparing
the power and energy efficiency is not an objective observation. It cannot be
concluded that for the system in question and the operational conditions
thereof that the energy efficiency would be less or more than the power
efficiency. This is true since if the power efficiency would be considered at a
low power level it would be lower than the calculated energy efficiency and
higher if considered at the optimal power efficiency. Needless to say a
performance indicator considering more operational factors when applicable
does constitute a maxim that is more noteworthy.
In reflection of the measurements obtained with the solar irradiation data and
the actual solar-PV panel it can be concluded that the outcome with the
emulated panel are proportionate. This dictates that the solar irradiation data
Thean Hoogenboezem Page 65
CHAPTER 6: CONCLUSION
obtained was accurate and that the calculations done to perform the emulation
have value to continuously reproduce experimental conditions similar to an
actual solar-PV panel. The merit of the experimental procedure exercised is
the achieved control over the experimental environment and other factors
influencing accurate measurements.
6.4. F UTURE W O RK
Energy efficiency as a performance indicator has many undiscovered
contributions to many different applications. There are many systems with
fluctuating operational conditions that are presently either not rated or
characterised. These systems may not be operating at their full potential or the
performance of these systems cannot be appropriately expressed with a single
figure. The concept of energy efficiency can be applied to many different
industries including renewable energy, power generator characterisation with a
continuously changing load, computer power supplies, central processing units
and mobile software applications’ effect on the battery life of mobile devices
to name but a few.
Energy relates to power yet contains the component of time, energy considers
the factor of an interval or duration. Accordingly calculating the energy
efficiency of the solar-PV water pump constituted a performance indicator
representing the entire operational interval. In the pursuance of calculating the
energy efficiency of a solar-PV water pump a suitable experimental setup was
constructed with components elected from a comparison of multiple water
pump units. The experimental setup was designed and constructed to allow
appropriate measurements to be acquired. These measurements of input
voltage, current and output flow rate was put to use to calculate the input and
output energy of the water pump. The first set of results has been obtained by
emulating a solar-PV panel from acquired solar irradiation data and the second
set of results has been obtained with an actual solar-PV panel.
The operational characteristics of the water pump unit are illustrated with
power efficiency plots from Figure 5-2, Figure 5-8 and Figure 5-9. Figure 5-2
represents the possible operational efficiencies achievable at different solar
irradiation levels. While Figure 5-8 and Figure 5-9 exhibit the achievable
power efficiencies under the emulated solar irradiation and with an actual
solar-PV panel portraying the daily operational performances. These plots
reinforce the fact that power efficiency as a performance indicator for solar-PV
water pumping systems cannot accurately present a single figure on the
operational performance. The five distinct pumping heights elected
demonstrate the progressive change in operation with the increase in pumping
height and allows identifying the optimum operational intervals within each
pumping height.
Reflecting on the power efficiency possibilities from Figure 5-8 and Figure 5-9
yields the conclusion that the power efficiency may be dictated as any value
from 0 % to ~4.5 % (at 0 m), 0 % to ~25 % (at 3.5 m), 0 % to ~35 % (at 7m), 0
% to ~34 % (at 10.5 m) or 0 % to ~23 % (at 14 m). These possible results for
the power efficiency strengthen the requirement of a single performance
indicator value to accurately reflect the expected performance during a daily
interval. This study presents the energy efficiency as the desired performance
indicator to accurately calculate a single value to reflect the daily performance
of a solar-PV water pumping system.
These energy efficiencies for the emulated case have been calculated as 2.5 %
(0 m), 19.1 % (3.5m), 30.3% (7 m), 31.1 % (10.5 m) and 15 % (14 m).
Accordingly the energy efficiencies calculated with an actual solar-PV panel
are 3.1 % (0 m), 19.5 % (3.5 m), 30.3 % (7 m), 29.5 % (10.5 m) and 23.5 %
(14 m). These results obtained are closely comparable except at 14 m where
the actual solar-PV panel produced better energy efficiency, this may be due to
measurements only being taken for half a day with an actual solar-PV panel.
These results obtained establishes that for the solar-PV water pumping system
in question and under the solar irradiation conditions experienced by this
system the energy efficiency is an accurate single value performance indicator.
The power efficiency allows identification of operational characteristics that
may not be established by calculation of the energy efficiency.
Resolutions on the project objectives are that the solar-PV water pumping
system components and factors influencing the system operation have been
identified and analysed. Many research sources have been utilised to analyse
and identify research short comings and factors that may be improved upon.
Performance indicators have been identified as an important part of solar-PV
water pumping systems where contributions can be made. The existing
performance indicators where studied and evaluated according to the value of
their results and energy efficiency was identified as a possible single value
performance indicator to present the single daily operation. In the pursuance of
experimentally verifying the energy efficiency of a solar-PV water pumping
system as a suitable indicator a suitable system was chosen and assembled to
validate the accuracy and usability of the energy efficiency.
7. REFERENCES
[1] K. Meah, S. Fletcher, and S. Ula, “Solar photovoltaic water pumping for remote
locations,” Renewable and Sustainable Energy Reviews, vol. 12, no. 2, pp. 472–487,
2008.
[2] B. D. Vick and R. N. Clark, “Determining the Optimum Solar Water Pumping System
for Domestic Use, Livestock Watering or Irrigation,” in American Solar Energy Society
Solar Conference, 8p. http://www. cprl. ars. usda. gov, 2009.
[4] A. Oi, “Design and simulation of photovoltaic water pumping system,” 2005.
[5] J. N. Shrestha, “Solar PV water pumping system for rural development in Nepal:
problems and prospects,” in Energy Conversion Engineering Conference, 1996. IECEC
96., Proceedings of the 31st Intersociety, 1996, vol. 3, pp. 1657–1662.
[6] T. Short and M. Mueller, “Solar powered water pumps: problems, pitfalls and
potential,” in Power Electronics, Machines and Drives, 2002. International Conference
on (Conf. Publ. No. 487), 2002, pp. 280–285.
[7] R. Scott, “Photovoltaic systems for rural communities in Indonesia,” in Energy for
Isolated Communities, IEE Colloquium on, 1988, pp. 1–1.
[8] S. Malla, C. Bhende, and S. Mishra, “Photovoltaic based water pumping system,” in
Energy, Automation, and Signal (ICEAS), 2011 International Conference on, 2011, pp.
1–4.
[9] A. Raturi, “Feasibility study of a solar water pumping system,” Applied Solar Energy,
vol. 47, no. 1, pp. 11–13, 2011.
[12] B. D. Vick and R. N. Clark, “Performance of wind-electric and solar-PV water pumping
systems for watering livestock,” TRANSACTIONS-AMERICAN SOCIETY OF
MECHANICAL ENGINEERS JOURNAL OF SOLAR ENERGY ENGINEERING, vol.
118, pp. 212–216, 1996.
[14] N. K. Lujara, J. van Wyk, and P. Materu, “Power electronic loss models of DC-DC
converters in photovoltaic applications,” in Industrial Electronics, 1998. Proceedings.
ISIE’98. IEEE International Symposium on, 1998, vol. 1, pp. 35–39.
[15] N. Lujara, J. Van Wyk, and P. Materu, “Loss models of photovoltaic water pumping
systems,” in Africon, 1999 IEEE, 1999, vol. 2, pp. 965–970.
[20] A. Betka and A. Attali, “Optimization of a photovoltaic pumping system based on the
optimal control theory,” Solar Energy, vol. 84, no. 7, pp. 1273–1283, 2010.
[21] G. M. Masters, Renewable and Efficient Electric Power Systems. Wiley, 2004.
[23] L. Castaner and S. Silvestre, Modelling Photovoltaic Systems Using PSpice. Wiley,
2003.
[26] N. Lujara, J. Van Wyk, and P. Materu, “Modelling Photovoltaic Water Pumping
Systems,” International Journal of Renewable Energy Engineering, vol. 2, no. 3, pp.
200–213, 2000.
[28] B. D. Vick and B. A. Neal, “Analysis of off-grid hybrid wind turbine/solar PV water
pumping systems,” Solar Energy, 2012.
[32] Z. Glasnovic and J. Margeta, “A model for optimal sizing of photovoltaic irrigation
water pumping systems,” Solar energy, vol. 81, no. 7, pp. 904–916, 2007.
[34] Z. Mingzhi and L. Zhizhang, “Design and Application of Off-Grid Solar PV System in
Inner Mongolia of China,” in Power and Energy Engineering Conference, 2009.
APPEEC 2009. Asia-Pacific, 2009, pp. 1–4.
[35] G. Whitfield, R. Bentley, and J. Burton, “Increasing the cost-effectiveness of small solar
photovoltaic pumping systems,” Renewable energy, vol. 6, no. 5, pp. 483–486, 1995.
[37] I. Odeh, Y. Yohanis, and B. Norton, “Economic viability of photovoltaic water pumping
systems,” Solar energy, vol. 80, no. 7, pp. 850–860, 2006.
[38] J. Appelbaum and M. Sarma, “The operation of permanent magnet DC motors powered
by a common source of solar cells,” Energy Conversion, IEEE Transactions on, vol. 4,
no. 4, pp. 635–642, 1989.
[40] K. Ramya and S. Rama Reddy, “Design and simulation of a photovoltaic induction
motor coupled water pumping system,” in Computing, Electronics and Electrical
Technologies (ICCEET), 2012 International Conference on, 2012, pp. 32–39.
[41] A. K. Daud and M. M. Mahmoud, “Solar powered induction motor-driven water pump
operating on a desert well, simulation and field tests,” Renewable energy, vol. 30, no. 5,
pp. 701–714, 2005.
[44] V. Vongmanee, “The Photovoltaic water pumping system using optimum slip control to
maximum power and efficiency,” in Power Tech, 2005 IEEE Russia, 2005, pp. 1–4.
[46] A. Moussi and A. Torki, “An Improved Efficiency Permanent Magnet Brushless DC
Motor PV Pumping System,” larhyss Journal, vol. 140, 2002.
[47] V. Salas, E. Olias, A. Barrado, and A. Lazaro, “Review of the maximum power point
tracking algorithms for stand-alone photovoltaic systems,” Solar energy materials and
solar cells, vol. 90, no. 11, pp. 1555–1578, 2006.
[48] N. K. Lujara, “Computer Aided Design of Systems for Solar Powered Water Pumping
By Photovoltaics,” 1999.
[49] O. Bolaji, R. Adu, and others, “Design Methodology for Photovoltaic Pumping System
Suitable for Rural Application in Nigeria,” Journal of Natural Sciences, Engineering
and Technology Formerly-ASSET: An International Journal (Series B), vol. 6, no. 1, pp.
120–130, 2010.
[50] I. Odeh, Y. Yohanis, and B. Norton, “Influence of pumping head, insolation and PV
array size on PV water pumping system performance,” Solar energy, vol. 80, no. 1, pp.
51–64, 2006.
A. APPENDIX A:
a. D ATA S HEETS
i. Yokogawa Instrumentation Manual
Radiation estimates
Page 1/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Page 2/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Page 3/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Outline of horizon with sun path for winter and summer solstice
Disclaimer:
The European Commission maintains this website to enhance public access to information about its initiatives and European Union policies in general. However the
Commission accepts no responsibility or liability whatsoever with regard to the information on this site.
This information is:
- of a general nature only and is not intended to address the specific circumstances of any particular individual or entity;
- not necessarily comprehensive, complete, accurate or up to date;
- not professional or legal advice (if you need specific advice, you should always consult a suitably qualified professional).
Some data or information on this site may have been created or structured in files or formats that are not error-free and we cannot guarantee that our service will not be
interrupted or otherwise affected by such problems. The Commission accepts no responsibility with regard to such problems incurred as a result of using this site or any
linked external sites.
Page 4/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Radiation estimates
Page 1/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Page 2/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Page 3/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Outline of horizon with sun path for winter and summer solstice
Disclaimer:
The European Commission maintains this website to enhance public access to information about its initiatives and European Union policies in general. However the
Commission accepts no responsibility or liability whatsoever with regard to the information on this site.
This information is:
- of a general nature only and is not intended to address the specific circumstances of any particular individual or entity;
- not necessarily comprehensive, complete, accurate or up to date;
- not professional or legal advice (if you need specific advice, you should always consult a suitably qualified professional).
Some data or information on this site may have been created or structured in files or formats that are not error-free and we cannot guarantee that our service will not be
interrupted or otherwise affected by such problems. The Commission accepts no responsibility with regard to such problems incurred as a result of using this site or any
linked external sites.
Page 4/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Radiation estimates
Page 1/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Page 2/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Page 3/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Outline of horizon with sun path for winter and summer solstice
Disclaimer:
The European Commission maintains this website to enhance public access to information about its initiatives and European Union policies in general. However the
Commission accepts no responsibility or liability whatsoever with regard to the information on this site.
This information is:
- of a general nature only and is not intended to address the specific circumstances of any particular individual or entity;
- not necessarily comprehensive, complete, accurate or up to date;
- not professional or legal advice (if you need specific advice, you should always consult a suitably qualified professional).
Some data or information on this site may have been created or structured in files or formats that are not error-free and we cannot guarantee that our service will not be
interrupted or otherwise affected by such problems. The Commission accepts no responsibility with regard to such problems incurred as a result of using this site or any
linked external sites.
Page 4/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Radiation estimates
Page 1/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Page 2/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Page 3/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Outline of horizon with sun path for winter and summer solstice
Disclaimer:
The European Commission maintains this website to enhance public access to information about its initiatives and European Union policies in general. However the
Commission accepts no responsibility or liability whatsoever with regard to the information on this site.
This information is:
- of a general nature only and is not intended to address the specific circumstances of any particular individual or entity;
- not necessarily comprehensive, complete, accurate or up to date;
- not professional or legal advice (if you need specific advice, you should always consult a suitably qualified professional).
Some data or information on this site may have been created or structured in files or formats that are not error-free and we cannot guarantee that our service will not be
interrupted or otherwise affected by such problems. The Commission accepts no responsibility with regard to such problems incurred as a result of using this site or any
linked external sites.
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European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Radiation estimates
Page 1/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
17:37 24 24 28 0 0 11 10 13
17:52 11 11 13 0 0 5 4 6
G: Global irradiance on a fixed plane (W/m2)
Gd: Diffuse irradiance on a fixed plane (W/m2)
Gc: Global clear-sky irradiance on a fixed plane (W/m2)
DNI: Direct normal irradiance (W/m2)
DNIc: Clear-sky direct normal irradiance (W/m2)
A: Global irradiance on 2-axis tracking plane (W/m2)
Ad: Diffuse irradiance on 2-axis tracking plane (W/m2)
Ac: Global clear-sky irradiance on 2-axis tracking plane (W/m2)
Page 2/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Page 3/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Outline of horizon with sun path for winter and summer solstice
Disclaimer:
The European Commission maintains this website to enhance public access to information about its initiatives and European Union policies in general. However the
Commission accepts no responsibility or liability whatsoever with regard to the information on this site.
This information is:
- of a general nature only and is not intended to address the specific circumstances of any particular individual or entity;
- not necessarily comprehensive, complete, accurate or up to date;
- not professional or legal advice (if you need specific advice, you should always consult a suitably qualified professional).
Some data or information on this site may have been created or structured in files or formats that are not error-free and we cannot guarantee that our service will not be
interrupted or otherwise affected by such problems. The Commission accepts no responsibility with regard to such problems incurred as a result of using this site or any
linked external sites.
Page 4/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Radiation estimates
Page 1/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Page 2/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Page 3/4
European Commission
Photovoltaic Geographical Information System Joint Research Centre
Ispra, Italy
Outline of horizon with sun path for winter and summer solstice
Disclaimer:
The European Commission maintains this website to enhance public access to information about its initiatives and European Union policies in general. However the
Commission accepts no responsibility or liability whatsoever with regard to the information on this site.
This information is:
- of a general nature only and is not intended to address the specific circumstances of any particular individual or entity;
- not necessarily comprehensive, complete, accurate or up to date;
- not professional or legal advice (if you need specific advice, you should always consult a suitably qualified professional).
Some data or information on this site may have been created or structured in files or formats that are not error-free and we cannot guarantee that our service will not be
interrupted or otherwise affected by such problems. The Commission accepts no responsibility with regard to such problems incurred as a result of using this site or any
linked external sites.
Page 4/4
APPENDICES
ii. Graph
DNI - Actual
AVE DNI, DNIc vs. Time supplied solar
1.2 radiation
DNIc - Clear sky
solar radiation
1
Solar Irradiation (kW.m2)
0.8
0.6
0.4
0.2
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
Figure A-1: Solar Irradiation for clear sky and actual operation for the daily annual
average
B. APPENDIX B:
a. S OLAR -PV W ATER PUMP C HARACTERISATIO N D ATA
i. Results
ii. Graphs
0.00035 14m
0.0003
17.5m
0.00025
0.0002
0.00015
0.0001
0.00005
0
0 100 200 300 400 500 600 700 800 900 1000
Solar Irradiation (W/m2)
Figure B-1: Water pump characterisation Flow Rate vs. incremental Solar Irradiation
30
3.5m
25
7m
20
15 10.5m
A_0m
10 14m
F_17.5m
5 17.5m
0
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
850
900
950
1000
Figure B-2: Water pump characterisation Power Efficiency vs incremental Solar Irradiation
Total 2875347
Q_Flow_Rate_0 (0PSI) (m^3/s)
Output_Power_Q_0m (0PSI)(Watts)
Energy_P_O_0m (Joules)
Actual Power Energy_Input_Used_3.5m Q_Flow_Rate(5PSI) (m^3/s)
Output_Power (5PSI)(Watts)
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
5.72082E-05 7.856979405 7071.281465
5.72082E-05 7.856979405 7071.281465
7.72798E-05 10.61360124 9552.241113
7.72798E-05 10.61360124 9552.241113
0.000115562 15.87134052 14284.20647
0.000115562 15.87134052 14284.20647
0.000115562 15.87134052 14284.20647
0.000115562 15.87134052 14284.20647
0.000115562 15.87134052 14284.20647
0.000115562 15.87134052 14284.20647
0.000115562 15.87134052 14284.20647
0.000164835 22.63846154 20374.61538
0.000164835 22.63846154 20374.61538
0.000164835 22.63846154 20374.61538
0.000164835 22.63846154 20374.61538
0.000164835 22.63846154 20374.61538
0.000164835 22.63846154 20374.61538
0.000164835 22.63846154 20374.61538
0.000164835 22.63846154 20374.61538
0.000164835 22.63846154 20374.61538
0.000164835 22.63846154 20374.61538
0.000164835 22.63846154 20374.61538
0.000164835 22.63846154 20374.61538
0.000115562 15.87134052 14284.20647
0.000115562 15.87134052 14284.20647
0.000115562 15.87134052 14284.20647
0.000115562 15.87134052 14284.20647
0.000115562 15.87134052 14284.20647
0.000115562 15.87134052 14284.20647
0.000115562 15.87134052 14284.20647
7.72798E-05 10.61360124 9552.241113
7.72798E-05 10.61360124 9552.241113
5.72082E-05 7.856979405 7071.281465
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
60
50
40
30
20
10
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
Figure B-3: Energy available, Energy input utilised and Energy Output of Water pump unit at 0m
discharge pressure
60
50
40
30
20
10
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
Figure B-4: Energy available, Energy input utilised and Energy Output of Water pump unit at 3.5m
discharge pressure
60
50
40
30
20
10
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
Figure B-5: Energy available, Energy input utilised and Energy Output of Water pump unit at 7m
discharge pressure
60
50
40
30
20
10
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
Figure B-6: Energy available, Energy input utilised and Energy Output of Water pump unit at 10.5m
discharge pressure
60
50
40
30
20
10
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
Figure B-5: Energy available, Energy input utilised and Energy Output of Water pump unit at 7m
discharge pressure
60
50
40
30
20
10
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
Figure B-6: Energy available, Energy input utilised and Energy Output of Water pump unit at 10.5m
discharge pressure
100
Energy vs. Time
Energy Avaiable
90
Energy_Input_14m
80
Energy_Output_14m
70
Energy (kJ)
60
50
40
30
20
10
0
05:37
06:07
06:37
07:07
07:37
08:07
08:37
09:07
09:37
10:07
10:37
11:07
11:37
12:07
12:37
13:07
13:37
14:07
14:37
15:07
15:37
16:07
16:37
17:07
17:37
18:07
18:37
Time (HH:MM)
Figure B-7: Energy available, Energy input utilised and Energy Output of Water pump unit at 14m
discharge pressure
Power_Efficiency_0m
Power Efficiency vs. Time Power_Efficiency_3.5m
40
Power_Efficiency_7m
35
Power_Efficiency_10.5
m
Power Efficiency (%)
30 Power_Efficiency_14m
25
20
15
10
Time (HH:MM)
Figure B-8: Power Efficiency plots for the five pumping heights over the daily operation interval for
the emulated case
Power_Efficiency_3.5m
30
25 Power_Efficiency_7m
20 Power_Efficiency_10.5m
15
Power_Efficiency_14m
10
5
0
Time (HH:MM:SS)
Figure B-9: Power efficiency plots of the five pumping heights for a morning operational interval with
an actual solar-PV panel