Renewable Microgrid Design for Remote Fijian Community

FACULTY OF ENGINEERING AND APPLIED SCIENCE
MECE3410U
Renewable Microgrid for a Community in Fiji
GROUP PROJECT REPORT
Course Instructor: Dr. Yuelei Yang
Teaching Assistant: Mohammed Alziadeh
Project Report Submitted On: April 11, 2016
# Last Name First Name ID
1 Bower Lowell 100500898
2 Karanwal Tushar 100481186
3 Owais Syed 100506689
4 Pandya Devarsh 100455628

MECE3410U - Renewable Microgrid for a Community in Fiji
1
Table of Contents
List of Figures................................................................................................................................. 2
List of Tables .................................................................................................................................. 3
1.0 Introduction............................................................................................................................... 4
1.1 Problem Statement................................................................................................................ 5
1.2 Project Objectives ................................................................................................................. 5
2.0 Design Details........................................................................................................................... 6
2.1 Proposed Design ................................................................................................................... 6
2.2 Project Assumptions ............................................................................................................. 7
3.0 Analysis and Discussion ........................................................................................................... 9
3.1 Component Selection............................................................................................................ 9
3.2 System Analysis.................................................................................................................. 16
3.3 Economic Analysis ............................................................................................................. 24
4.0 Conclusion .............................................................................................................................. 27
5.0 Nomenclature.......................................................................................................................... 28
6.0 Appendix................................................................................................................................. 29
6.1 Figures................................................................................................................................. 29
6.2 Sample Calculations............................................................................................................ 33
6.3 EES Code and Results ........................................................................................................ 35
References..................................................................................................................................... 37

2
List of Figures
Figure 1: Map of Fiji [21].............................................................................................................. 4
Figure 2: Proposed system diagram................................................................................................ 6
Figure 3: Geothermal Organic Rankine Cycle................................................................................ 9
Figure 4: R134a Molecular Structure ............................................................................................. 9
Figure 5:40 VSI Leroy Somer alternator ...................................................................................... 10
Figure 6: T701 wind turbine from Pika Energy............................................................................ 11
Figure 7: Vertical gin pole from ARE and Econotower from Pika Energy.................................. 12
Figure 8: B801 battery charge controller from Pika Energy......................................................... 13
Figure 9: X7601 islanding inverter from Pika Energy.................................................................. 14
Figure 10: 12 CS 11P deep cycle battery from Rolls.................................................................... 15
Figure 24: T-S diagram of ORC process ...................................................................................... 16
Figure 25: Zoomed in to see states 3 and 4................................................................................... 16
Figure 11: Efficiency curve of the LSA 40 VS1 operating at 50 Hz [7]. ..................................... 18
Figure 12: Short-circuit curve for start-up of LSA 40 VS1 [7]. ................................................... 18
Figure 13: Equivalent circuit (a) and phasor diagram (b) for a synchronous generator [13] ....... 19
Figure 14: Variable-speed system with full capacity converters [13] .......................................... 19
Figure 15: Active-stall control of a wind turbine [13].................................................................. 20
Figure 16: Average wind speed in Fiji.......................................................................................... 20
Figure 17: T701 turbine power curve ........................................................................................... 21
Figure 18: Estimated turbine power output by month .................................................................. 21
Figure 19: Series/parallel connection of batteries [11]................................................................. 22
Figure 20: Clockwise Rotation Phase Sequence (1-2-3) [14]....................................................... 23
Figure 21: Counter Clockwise Rotation Phase Sequence (3-2-1) [14]......................................... 23
Figure 22: Generator Frequency Lower than Grid’s [14]............................................................. 24
Figure 23: Generator and Grid in Phase [14]................................................................................ 24
Figure 26: Full-scale proposed system diagram ........................................................................... 29
Figure 27: Fiji power grid [3] ....................................................................................................... 30
Figure 28: Number of cycles vs. depth of discharge for 12 CS 11P battery [22]......................... 31
Figure 29: EES Results................................................................................................................. 36

3
List of Tables
Table 1: ORC component parameters............................................................................................. 9
Table 2: LSA 40 VSI component parameters [7] ......................................................................... 10
Table 3: T701 wind turbine component parameters ..................................................................... 11
Table 4: Econotower and gin pole component parameters [8] [10].............................................. 12
Table 5: B801 charge controller component parameters [8] ........................................................ 13
Table 6: X7601 inverter component parameters [8]..................................................................... 14
Table 7: 12 CS 11P battery component parameters [12].............................................................. 15
Table 8: Tabulated state values of ORC ....................................................................................... 17
Table 9: Cost break down for ORC .............................................................................................. 25
Table 10: Cost breakdown for wind turbine and associated components..................................... 25
Table 11: Economic summary ...................................................................................................... 26

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1.0 Introduction
The nation of Fiji is located in the Pacific Ocean and comprised of 332 islands; approximately 110
of which are inhabited [1]. The country has a total population of 909,389 contained within a total
land area the size of New Jersey. In 2015, 1150.5 GWh of electricity was produced with renewable
generation comprising 90.9% of total production [2]. This remarkably high percentage of
renewable generation is the result of a dedicated effort by the Fijian government to reduce the need
for costly fossil fuel imports. They have set the target of 100% renewable energy generation by
2020 and appear to be on track to realize this goal [3]. Renewable sources of energy are primarily
Figure 1: Map of Fiji [21]

5
hydroelectric with biomass, solar, and wind contributing a smaller share (see Figure 27). The
primary source of non-renewable energy is diesel which must be imported.
This report will propose and analyze a renewable energy microgrid for a small community on one
of the islands within Fiji. Since only renewable energy has been specified for the microgrid, a
primary and secondary source of energy will be used to ensure a constant supply of power. The
International Renewable Energy Agency (IRENA) has identified that an increase in non-hydro
renewables would diversify the energy mix and add resilience to the energy grid in Fiji.
Additionally, both IRENA and an analysis by McCoy-West et al. [4] have determined that the
nation has a high development potential for geothermal energy with 53 thermal areas identified
from detailed surveys. Based on this information geothermal energy has been selected as the
primary source of power for the community. An analysis of wind power prospects in Fiji was
carried out by Kumar and Prasad [5] which determined that most sites have a moderate potential
for wind generation during the months of April to October with an average power density of
approximately 160 W/m2
. The sites are less suited to wind power generation during the months of
November to march with an average power density of 100 W/m2
. Wind energy has therefore been
selected as the secondary source of energy since it is less reliable compared with the approximately
constant generation of a geothermal site.
1.1 Problem Statement
A small community of 100 occupants on the islands of Fiji requires an energy generation system.
The island has sufficient wind and sunshine. This community consumes an average of 6000 kWh
of electricity per month. To plan for any changes in load, this consumption will be increased by
20% to a total of 7200 kWh (~9.7 kW)
1.2 Project Objectives
 Identify the primary and secondary energy sources
 Create a schematic of the system
 Select and size a type of generator and determine its rated parameters
 Perform an economic analysis

6
2.0 Design Details
2.1 Proposed Design
Figure 2: Proposed system diagram
The proposed design shown above is the micro grid which will provide enough energy for a
community of 100 occupants in Fiji. The primary energy source of this micro grid is a supply of a
hot geothermal water. This constant supply of heat runs an organic Rankine cycle (ORC) which
has R-134a circulating as working fluid.
Referring to Figure 2, the ORC has four main components: turbine, condenser, pump, and heat
exchanger. The heat exchanger is used to transfer the heat from the well water from the geothermal
boreholes to the working fluid. This causes the working fluid to change phase to super-heated
vapor. The high quality super-heated vapor is then fed into a turbine, where it is expanded from
high pressure to low pressure. Mechanical work is produced from the turbine which is connected
to a 3 phase synchronous generator which is the primary power source for the community. The
expansion of the working fluid causes a decrease in entropy, and the resulting outlet stream from

7
the turbine is a mixture of vapor and liquid. The condenser is used as a heat dump; cooling water
lines sourced from the ocean provide sufficient cooling to induce phase change to saturated liquid.
This is crucial as it is not possible to compress a mixture without experiencing cavitation damage
to the compressor. The pump is used to pressurize the saturated liquid to desired levels before the
addition of heat from the geothermal source.
The secondary power source is three T701 wind turbines which converts the kinetic energy of the
wind into a 190 V DC power output. A lightning arrestor is included at the base of the tower to
protect the system from a direct lighting strike. The junction box connects the three wind turbines
and the DC disconnect allows this portion of the system to be isolated for maintenance. The B801
charge controller manages the flow of energy from the wind turbines and 3 phase synchronous
generator to the battery bank. The controller is bi-directional and transforms power between the
190 V DC incoming from the turbines, 48 V DC battery bank voltage, and 380 V DC output. The
battery bank is comprised of eight batteries connected in series-parallel for increased voltage and
capacity. The inverter connects the DC and AC portions of the proposed system and allows for bi-
directional flow so that the primary 3 phase synchronous generator can charge the battery bank.
Both the streams of electricity from the organic Rankine cycle-generator unit and the wind turbines
are synchronized to ensure no damage to the generator or micro grid occur. After the
synchronization module, the voltage is stepped up by the use of a transformer. This is to reduce
transmission losses as the power flows through the distribution grid. To supply energy to the
occupants, the voltage is stepped down after transmission and sent to homes in the community.
The electricity standard for Fiji is 240 V at 50 Hz [3] and the system was designed to meet this
requirement. Although the power grid on the community is isolated, electronics and appliances
will likely be designed to work with this standard.
2.2 Project Assumptions
ORC:
- No leaks
- No losses in pipes and fittings
- Constant geothermal temp
- Constant mass flows of fluids
- Heat exchanger efficiencies are 100%
- 10 degree gradient for effective heat exchange
3ϕ Synchronous Generator:
- Manufactured by solid steel forging
- Rotor is 2/3 slotted for windings and 1/3 unslotted for behaviour as pole

8
- Speed of 1500 rpm with 4 poles
- Nonsalient pole alternator must be selected for high speed application
- Peripheral velocity below 175 m/s to dictate physical dimensions
- Short Circuit Ratio (SCR) between 0.7 and 1.1
- Current density between 3 A/mm and 5 A/mm
- Stator current must be less than 1500 A
- Single turn coils required for 1500 rpm and simplicity in design
- Coils assumed to be full pitched and corresponding winding factor (𝑘 𝑤) is 0.955
- Synchronous generator was assumed to be in Y-connection
Wind:
- Air properties 25C and 1 atm
Power Grid
- Transmission losses are negligible
- Distribution grid is existing
- The electricity used in the community is 240 V at 50 Hz

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3.0 Analysis and Discussion
3.1 Component Selection
Geothermal Organic Rankine Cycle
Figure 3: Geothermal Organic Rankine Cycle
The primary power source for this community will be a Geothermal Organic Rankine Cycle
(GORC). The system uses 1,1,1,2 Tetrafluoroethane (R134a), as the working fluid.
Table 1: ORC component parameters
Technology
Produced Power
Range
Heat Source
Temperature Range
Turbines
Micro ORC 10 kW Around 100˚C
Lysholm Turbine –
60% of cost
Heat Exchangers Working fluid Size Cost
Compact brazed heat
exchangers
R134a, R245fa, R22,
Other Refrigerants
0.6·1.5·1.5 (m3
) $25000 - $2500/kW
Figure 4: R134a
Molecular Structure

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Synchronous Generator
3ϕ synchronous generator for the Organic Rankine Cycle (ORC) was selected based on several
design considerations to ensure optimal functionality with the proposed system. The LSA (Leroy
Somer Alternator) 40 VS1 was chosen to operate along with the ORC. This is a 3ϕ 1500 rpm, 50
Hz, 380 V, 10.5 kVA turbo alternator. The synchronous generator can be operated at 8.4 kW under
rated operating conditions while assuming a power factor of 0.8. Some of the other specifications
of this low voltage turbo alternator are that the winding pitch is approximately 2/3. The insulation
class of this alternator is H meaning the generator can operate at 155°C at a thermal life expectancy
of 100,000 working hours instead of the typical 20,000 to 25,000 working hours [6] .The maximum
working temperature of this class insulation is approximately 180° C [6]. The efficiency of the
LSA 40 VS1 is approximately 88.7% which is observed to be about 2% lower than the 60 Hz
model at the same rated conditions.
Table 2: LSA 40 VSI component parameters [7]
Rated Power Output
(kVA)
Rated Voltage Output
(V)
Rotational Speed
(rpm)
10.5 380 1500
Figure 5:40 VSI Leroy Somer alternator

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Wind Turbine
The wind turbines selected for the community are a T701 model manufactured by Pika Energy.
The three-blades on this horizontal-axis wind turbine (HAWT) are glass-reinforced polymer and
the nacelle has an upwind rotor with free yaw. The system includes a brushless permanent magnet
AC generator with slip ring design. The generated AC power is rectified into DC voltage for
transmission within the microgrid. This turbine can be connected to a Wi-Fi remote monitoring
system and has been has received a Limited Power Performance (LPP) certification by the Small
Wind Certification Council (SWCC) [8]. The parameters for this turbine are summarized below.
Table 3: T701 wind turbine component parameters
Peak Power Output
(kW)
Rated Power Output
(kW)
Output Voltage
(V DC)
1.7 @ 13.5 m/s 1.5 @ 11 m/s 190
Cut In Wind Speed
(m/s)
Survival Wind Speed
(m/s)
Swept Area
(m2
)
3.3 66 7.1
Figure 6: T701 wind turbine from Pika Energy

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Wind Tower
The wind tower will be an Econotower from Pika Energy combined with a vertical gin pole from
American Resource & Energy (ARE). The windtower is a modular system that can be made with
locally sourced pipe sections and is designed to be used with eight supporting guy wires. The
vertical gin pole allows for easy setup by one person and would be left attached to the windtower
so that it could be quickly disassembled and secured in the event of dangerously high winds. The
wind turbine has a wind survival speed of 66 m/s (237.7 km/hr), however during cyclone Winston
gusts of up to 84.7 m/s (305 km/hr) were recorded on the island of Fiji [9]. An additional advantage
of a non-permanent installation is that the turbine can be lowered for service.
Table 4: Econotower and gin pole component parameters [8] [10]
Total Height
(m)
Econotower Tube
Ginpole Weight Capacity
(kg)
12.8 Sched. 40 2.5 inch diameter 2048
Figure 7: Vertical gin pole from ARE and Econotower from Pika Energy

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Charge Controller
The B801 charge controller is used to manage the flow of DC power from the wind turbines to the
battery bank and inverter used in the microgrid. The charge controller will step up the incoming
turbine voltage of 190 V to 380 V to reduce line losses. The controller will prioritize loads and
manage battery storage to ensure the maximum number of cycles can be reached within the bank.
Protection features include sensors for over/under voltage, high temperatures within the controller
and battery bank, and high current flow.
Table 5: B801 charge controller component parameters [8]
Rated Power
(W)
Rated Input Voltage
(V DC)
Rated Input Current
(A)
4000 190 10
Rated Output Voltage
(V DC)
Battery Voltage
(V DC)
Max. Battery Current
(A)
380 24 to 48 80
Efficiency
(%)
Standby Power Consumption
(W)
Temperature Range
(°C)
95 7 -20 to 50
Figure 8: B801 battery charge controller from Pika Energy

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Inverter
The inverter for the system is an X7601 islanding inverter which will convert the DC power output
of the charge controller to the AC power used in the distribution system for the microgrid.
Although capable of connecting directly to lithium ion batteries, lead acid batteries have been
specified for the system requiring the additional battery charge controller. The inverter allows for
bi-directional energy flow so that the primary synchronous generator can also be used to charge
the batteries if required. Additionally, an internal autotransformer can be used to support critical
loads within the community.
Table 6: X7601 inverter component parameters [8]
Rated Continuous Power
(W)
Rated Surge Power
(W)
Rated Input Voltage
(V DC)
8000 12000 for 10 seconds 380
Rated Output Voltage
(V AC)
Peak Efficiency
(%)
Max. Temperature
(°C)
3𝜙 208 V @ 60 Hz 97 60
Figure 9: X7601 islanding inverter from Pika Energy

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Battery Bank
The battery bank for the proposed microgrid will consist of eight 12 CS 11P deep cycle lead acid
batteries connected in a series and parallel. A bank of batteries connected in series will have a total
voltage equal to the sum of each batteries voltage while maintaining the amp hour capacity of a
single battery. While a bank of batteries connected in parallel will have a total capacity equal to
the sum of each batteries capacity with a voltage of a single battery. By connecting the battery in
series and parallel both the operating voltage and amp hour capacity can be increased [11]. This
battery was selected due to the very favorable relationship between number of cycles and depth of
discharge reaching a 50% discharge after approximately 3200 cycles (see Figure 28).
Table 7: 12 CS 11P battery component parameters [12]
Single Battery Voltage
(V DC)
Single Battery Amp Hour
(A)
Specific Gravity
12 357 1.280
Figure 10: 12 CS 11P deep cycle battery from Rolls

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3.2 System Analysis
The following section analyzes the main components of the system. Sample calculations and the
created EES code are included in the Appendix.
Geothermal Organic Rankine Cycle
The GORC was simulated using Engineering Equation Solver with parameters outlined in
Appendix 6.3 EES Code. The following figures show the temperature-entropy plots of the process.
Figure 11: T-S diagram of ORC process
Figure 12: Zoomed in to see states 3 and 4

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In an ideal situation, the all expansions in the process would be isentropic, and all heat additions
in the process would be isobaric. For this simulation we introduced turbine and pump efficiencies
of 90% and 80% respectively, to get an accurate estimation of mass flows and work inputs for the
proposed system. The state properties are shown below:
Table 8: Tabulated state values of ORC
State
Enthalpy
(kJ/kg)
Pressure
(kPa)
Energy Rate
(kW)
Entropy
(kJ/kg-K)
Temperature
(C)
1 303.9 2500 98.14 0.9569 92.2
2 276 600 89.14 0.967 35.34
3 81.51 600 26.32 0.308 21.55
4 83.45 2500 26.95 0.3093 22.82
5 169.6 2500 - 0.5753 77.54
Setting the power demand at 9 kW, the mass flow rate of the working fluid (R134) is determined
to be 0.323 kg/s which is a reasonable flowrate considering the peak load the cycle has to produce.
Thermal efficiency is calculated by using the specific work of working fluid in the boiler divided
by the difference in enthalpy of working fluid at turbine inlet and outlet. The proposed design is
11.76% thermally efficient which is within the rage of commercially available Organic Rankine
Cycles.
Synchronous Generator
The 3ϕ synchronous generator selected for the electrical infrastructure designed was chosen based
on several design parameters. As mentioned above, an Organic Rankine Cycle feeds into the
synchronous generator. The ORC turbine behaves similarly to steam turbines commonly found
and thus require a generator that work at a high speed. The speed of the turbo alternator was chosen
to be 1500 rpm in order to meet this requirement. The LSA 40 VS1 was chosen based on the
working conditions and assumptions specified above. The synchronous speed as dictated by the
fundamental relation with 4 poles and a frequency of 50 Hz was 1500 rpm (𝑁𝑠) or 25 rps (𝑛 𝑠) as
required for some design considerations that will be discussed below.
Peripheral speed is defined as: 𝑛 𝑝 = 𝜋𝐷𝑟 𝑛 𝑠 where 𝐷𝑟 is the rotor diameter. The rotor diameter can
be chosen based on a suitable peripheral velocity or vice versa depending on the design constraints.
The design constraint was to be below 175 m/s for the peripheral velocity so a value of 100 m/s
was selected. The Short Circuit Ratio (SCR) was found to be 0.7 for the LSA 40 VS1 which was
in the required bounds of the design [6]. Furthermore, the efficiency of the generator can be
analyzed over the range of apparent powers that the generator may output. The ideal scenario with
a power factor of 1 on the 50 Hz LSA 40 VS1 yields approximately 88.7% efficiency and this

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efficiency is optimized at 88.8% at 8 kVA [6]. The altered scenario where the system operates at
a power factor of 0.8 yields lower efficiency of 82.7% at the 10.5 kVA rating selected for the
application with the ORC.
Figure 13: Efficiency curve of the LSA 40 VS1 operating at 50 Hz [7].
Figure 14: Short-circuit curve for start-up of LSA 40 VS1 [7].
Figure 14 shown above is the short-circuit curve in the Y connection as required for the system.
The Y-connection is preferred to reduce the insulation required due to 58% reduction in the voltage
per phase (resulting from the factor of 1/√3) between the slots and increase the cross sectional area
of the conductors. The increased current corresponds to a higher power output as well which is a
typical requirement of the turbo alternators. The delta connection was avoided since it is known to
distort line voltages significantly instead of crossing them out like a Y-connection when a lagging
load is attached to the system. The figure above can be used for understanding the transient
characteristics of the generator at start up.

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Wind Turbine
Figure 15 shows the equivalent circuit and phasor diagram for a synchronous generator. The main
difference between most synchronous generators and the selected wind turbine is that the
excitation voltage (𝐸𝑓) will be created due to the flux generated by mechanical rotation of the
permanent magnets instead of an external power source [13]. In this type of generator the stator
winding flux (𝛷𝑎) due to the current 𝐼 𝑎 is linked with leakage flux (𝛷 𝑎𝑙) but does not impact the
field winding. The armature reaction flux (𝛷𝑎𝑟) however does link with the field winding and acts
against the flux, reducing power production.
The turbine selected for the community is permanent magnet synchronous generator (PMSG)
combined with full capacity power converters (see Figure 16). These converters transform the AC
output of the PMSG into the 190 V DC output of the turbine.
Figure 15: Equivalent circuit (a) and phasor diagram (b) for a synchronous generator [13]
Figure 16: Variable-speed system with full capacity converters [13]

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Speed control is accomplished by electronic stall regulation which is a type of active-stall control.
To avoid damaging the turbine at high wind speeds, turbines must have some type of speed control
that limits the rotational speed while producing maximum power. For electronic stall control, the
blade angle of the turbine is increased so that turbulence develops on the back of the blade and
rotational speed is reduced (see Figure 17).
Wind Energy
The power output of the wind turbines can be estimated using average monthly wind speeds
measured in Fiji at various sites (see Figure 18) which was created by finding the midpoint through
measured data from Kumar and Prasad [5].
The performance curve for the T701 wind turbine was created using data from a Small Wind
Certification Council (SWCC) report [8] and used to create the relation between wind speed and
Figure 17: Active-stall control of a wind turbine [13]
5.0
5.5
6.0
6.5
7.0
7.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13
AverageWindSpeed(m/s)
Jan Feb Mar Apr May Jun Jul Aug Oct Sep Nov Dec
Figure 18: Average wind speed in Fiji

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turbine power output seen in Figure 19. The wind speed range encountered in Fiji has a minimum
and maximum value of 5.4 m/s and 7.2 m/s respectively and a trendline was created for this portion
of the power curve. The curve at this point is approximately linear with an R2
value of 0.9863.
The monthly estimated power output for the three turbines was then calculated based on the
trendline for the region of interest and can be seen in Figure 20. The maximum output of the three
turbines is 1448 W and was reached in July and the minimum output of 534 W for February. The
average yearly output of the three turbines is approximately 1035 W.
y = 164.69x - 702.95
R² = 0.9863
0
200
400
600
800
1000
1200
1400
1600
1800
2000
0 5 10 15 20
PowerOutput(W)
Wind Speed (m/s)
Figure 19: T701 turbine power curve
200
400
600
800
1000
1200
1400
1600
0 1 2 3 4 5 6 7 8 9 10 11 12 13
PowerOutput(W)
Figure 20: Estimated turbine power output by month
Jan Feb Mar Apr May Jun Jul Aug Oct Sep Nov Dec

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The efficiency of the microgrid (𝜂 𝑀𝐺) was calculated and includes the efficiency of the charge
controller and inverter. For the proposed system 𝜂 𝑀𝐺 was calculated to be approximately 92.1%.
Therefore the actual output of the turbine will be decreased. Assuming that transmission losses to
the inverter are negligible, the peak power output of one wind turbine will be reduced from 482.8
W to 444.9 W. Considering these losses the yearly output of the three wind turbines is
approximately 8379 kWh. The efficiency of a single turbine in terms of converting the kinetic
energy of the wind into electrical energy (𝜂 𝑊𝑇) was also calculated considering the maximum and
minimum wind speed of 7.2 m/s and 5.2 m/s respectively. The efficiency range under these
conditions was approximately 30.9% to 27.0%.
Battery Bank Capacity
The battery bank of eight deep cycle batteries have been connected in series and parallel in order
to increase the system voltage and amp hour capacity (see Figure 21). The rating for a single 12
CS 11P battery is 12 V DC and 357 amp hours (Ah). The system voltage for the battery bank is
therefore 48 V DC with a 2856 Ah capacity. It is recommended to keep above a 50% discharge
for normal use of batteries [11], therefore the rated capacity of the battery bank well be assumed
to actually be 1428 Ah. Since the rated power for the charger controller is 4.0 kW, the community
could be run at half capacity in the event of both the primary and secondary energy sources failing.
In this scenario community could be run entirely off the battery bank at half consumption for
approximately 2.8 days.
AC Power Synchronizing
To synchronize different outputs from generators to a grid, four parameters must be met. The first
is the phase sequence (or phase rotation). This is the sequence of the phase angle shift between the
three winding pairs. An example of the two possible rotation phase sequences is shown in the
Figure 21: Series/parallel connection of batteries [11]

23
images below. When the magnet of a generator is rotating, the peak instantaneous voltage of the
windings will usually be 120° from each other.
Figure 22: Clockwise Rotation Phase Sequence (1-2-3) [14]
Figure 23: Counter Clockwise Rotation Phase Sequence (3-2-1) [14]
The voltage also needs to be matched in order to synchronize different outputs of AC power. In
order to achieve this the magnitude voltage of the incoming generator must be matched to the
sinusoidal voltage of the grid [14]. If the two voltage do not match, a voltage differential will be
produced. If the generator’s voltage is higher, the generator will be overexcited and it will put out
MVAR [14]. If the generator voltage is less than the grid’s, then the generator will absorb apparent
power.
Frequency of the generator and the power grid must be equal, or it would cause damage to the
generator. Usually syncroscopes, essentially an electronic machine which displays different wave
forms, are used to match these frequencies. If the generator’s frequency is slower than the grid’s,
as shown in the figure below, then the generator would behave like a motor. This is due to the grid
trying to match the generator to the grid [14]. This would cause slipping poles between the rotor
and stator and could possibly damage the generator. If the generator’s frequency was higher than
the grid, then the generator would input power into the grid [14]. This would be in the form of a
very high current rush.

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Figure 24: Generator Frequency Lower than Grid’s [14]
Lastly, the phase angle between the generator and grid has to be zero. This is usually done by
comparing the peaks or zero crossings of sinusoidal waveforms.
Figure 25: Generator and Grid in Phase [14]
3.3 Economic Analysis
Diesel Mitigation
Currently, diesel is one of the methods used to generate electricity in Fiji [15]. The proposed design
will aim to mitigate the use of diesel. Typical diesel generators use 0.4 litres of diesel for every
kWh they produce [16]. To produce the annual electricity for the 100 occupant community, a total
of 28,800 litres of diesel will be required. At the moment, diesel costs $0.73 per litre. The cost to
provide for the energy needs of the community would be $21,024 annually.
The diesel consumption of the community has been estimated at 28,800 L/year and this value can
be used to estimate the kilograms of CO2 that have been removed from the atmosphere due to the
installation of this microgrid. Given an estimated emission factor of 2535 g/L for diesel fuel used
in electricity production [17], using the proposed microgrid has removed approximately 73,008 kg
of CO2 from the atmosphere each year.

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Organic Rankine Cycle and Generator
Table 9: Cost break down for ORC
Component
Number of
Components
Unit Cost
(CAD)
Purchase Cost
(CAD)
Micro ORC 1 $25000 [18] $25000
Total Purchase Cost
(CAD)
$25000
Installation Cost
(CAD)
$250000 [18]
Total Cost
(CAD)
$275000
Referring to the above table, the total principle cost for implementing a Geothermal Organic
Rankine Cycle is $275,000 [19]. The costs attributed to geothermal drilling are usually high. The
price per foot of depth is approximately $2600 [19]. Operational and maintenance costs related to
organic rankine cycles are usually lower than steam power plants, due to less moving parts. The
O&M costs to run an ORC is approximately $0.01/kWh [15]. The total O&M costs to run this
proposed system is approximately $720 annually.
Wind Energy
Table 10: Cost breakdown for wind turbine and associated components
Component
Number of
Components
Unit Cost
(CAD)
Purchase Cost
(CAD)
Wind Turbine 3 $5995 [20] $17985
Wind Tower/Gin Pole 3 $4500 [20] $13500
Charge Controller 1 $0 $0
Inverter 1 $2000 $2000
Battery 8 $1055 [21] $8440
Total Purchase Cost
(CAD)
$41925
Installation Cost
(CAD)
$25000 [22]
Total Cost
(CAD)
$66925
Table 3 summarizes the initial cost for the wind turbine and associated components. There is no
cost for the charge controller because it is included in the cost of the turbine. A cost for the inverter
could not be found when the report was created and was assumed based on inverters of a similar
capacity. The installation cost was the upper limit estimated by Bergey Wind Power but is likely

26
an underestimate given the difficulties of installing on a remote Pacific island. The shipping cost
of the components was not included and could significantly increase the cost.
Economic Overview and Payback Period
The total costs of the proposed micro grid are shown in the table below.
Table 11: Economic summary
Component
Capital Investment
(CAD)
Operations and Management (O&M)
(CAD/year)
Micro ORC $275000.00 [18]
$720.00
Synchronous Generator $5100.00
Wind Energy Components $66925 $234
Total Capital Cost
(CAD)
$347025.03
Total Annual O&M Cost
(CAD)
$954
The total capital investments are upwards of $350,000. The total operational and maintenance
costs can range up to a total of $1000 annually. The low O&M costs of the ORC is much more
appealing than implementing a steam generator. A majority of this costs is attributed to the
borehole and geotechnical services required to set up the geothermal organic rankine cycle.
It is important to know the moment when the capital investment of the proposed design would pay
for itself. The savings from diesel annually are $21,024. Factoring in the total O&M costs, a net
savings of $20,070 annually is estimated. The payback period for the total capital investment
shown in the table above would then be achieved in the 17th
year of operation.

27
4.0 Conclusion
This report has proposed a micro grid to be installed on the islands of Fiji to provide electricity for
100 occupants. A primary energy source of hot geothermal water was used to heat an organic
Rankine cycle (ORC). The ORC provides 9 kW in order to provide 100% of the energy that the
community needs. The turbine of the ORC is paired with a 3 phase synchronous generator which
runs at 1500 rpm, providing 380 V output at 50 Hz rated for 10.5 kVa. The generator runs at 0.8
power factor, which provides 8.4 kW at rated speed. Estimated monthly output from the
synchronous generator is therefore a constant 6250 kWh.
Wind is used as a secondary energy source to supplement generation from the ORC. Maximum
power output from the three wind turbines occurs between the months of May to August. After
including the microgrid efficiency, the output during this time is approximately 900 kWh. Output
during the period from September to April is lower and fluctuates between 350 and 750 kWh. This
secondary source of power would satisfy peak demands and provide a backup source of power if
the primary system failed or required service. Considering both sources the maximum power
output is 7250 kWh and the minimum power output is 6580 kWh. This means that an excess of
21% to 10% of power is produced by the proposed system.
The micro grid also implements a large battery bank, which is used in the event of a large power
outage. The battery bank alone will be able to provide 50% of the power supply for the community
for a period of approximately 2.8 days.
The micro grid were also analyzed based on economic and environmental impacts. Due to Fiji
currently burning diesel to provide energy, this was used as a control case. 28,800 litres of diesel
would provide the necessary 6000 kWh for the community. A total capital investment of
approximately $350,000 was estimated, with operations and maintenance costs of $1000 annually.
The payback period attributed to this was equal to 17.3 years, factoring in the savings from not
importing diesel. When the micro grid was used, the diesel usage was eliminated and replaced with
clean and alternate energy sources. This mitigated approximately 73,000 kg of CO2 which would
have been released into the atmosphere.

28
5.0 Nomenclature
General
𝐴 − 𝐴𝑟𝑒𝑎 [𝑚2]
𝐶 − 𝐶𝑎𝑝𝑎𝑐𝑖𝑡𝑦 [𝐴ℎ]
𝐷𝑟 − 𝑅𝑜𝑡𝑜𝑟 𝑑𝑖𝑎𝑚𝑒𝑡𝑒𝑟 [𝑚]
𝐸𝑓 − 𝐸𝑥𝑐𝑖𝑡𝑎𝑡𝑖𝑜𝑛 𝑣𝑜𝑙𝑡𝑎𝑔𝑒 [𝑉]
𝐼 − 𝐶𝑢𝑟𝑟𝑒𝑛𝑡 [𝐴]
𝑘 𝑤 − 𝑊𝑖𝑛𝑑𝑖𝑛𝑔 𝑓𝑎𝑐𝑡𝑜𝑟
𝑚̇ − 𝑀𝑎𝑠𝑠 𝐹𝑙𝑜𝑤 𝑅𝑎𝑡𝑒 [
𝑘𝑔
𝑠
]
𝑁 − 𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑏𝑎𝑡𝑡𝑒𝑟𝑖𝑒𝑠
𝑛 𝑝 − 𝑃𝑒𝑟𝑖𝑝ℎ𝑒𝑟𝑎𝑙 𝑠𝑝𝑒𝑒𝑑 [
𝑚
𝑠
]
𝑛 𝑠 − 𝑆𝑦𝑛𝑐ℎ𝑟𝑜𝑛𝑜𝑢𝑠 𝑠𝑝𝑒𝑒𝑑 [𝑟𝑝𝑠]
𝑁𝑠 − 𝑆𝑦𝑛𝑐ℎ𝑟𝑜𝑛𝑜𝑢𝑠 𝑠𝑝𝑒𝑒𝑑 [𝑟𝑝𝑚]
𝑃 − 𝑃𝑜𝑤𝑒𝑟 [𝑊]
𝑡 − 𝑡𝑖𝑚𝑒 [𝑠 𝑜𝑟 ℎ𝑟 𝑜𝑟 𝑑𝑎𝑦𝑠]
𝑉 − 𝑉𝑒𝑙𝑜𝑐𝑖𝑡𝑦 [
𝑚
𝑠
] 𝑜𝑟 𝑉𝑜𝑙𝑡𝑎𝑔𝑒 [𝑉]
Greek Letters
𝜂 − 𝐸𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑐𝑦 [𝑑𝑖𝑚𝑒𝑛𝑠𝑖𝑜𝑛𝑙𝑒𝑠𝑠 𝑜𝑟 %]
𝜌 − 𝐷𝑒𝑛𝑠𝑖𝑡𝑦 [
𝑘𝑔
𝑚3
]
Subscripts
𝑏𝑎𝑛𝑘 − 𝐵𝑎𝑡𝑡𝑒𝑟𝑦 𝐵𝑎𝑛𝑘
𝑏𝑎𝑡𝑡 − 𝑆𝑖𝑛𝑔𝑙𝑒 𝐵𝑎𝑡𝑡𝑒𝑟𝑦
𝑐𝑐 − 𝐶ℎ𝑎𝑟𝑔𝑒 𝑐𝑜𝑛𝑡𝑟𝑜𝑙𝑙𝑒𝑟
𝑖 − 𝐼𝑛𝑣𝑒𝑟𝑡𝑒𝑟
𝑚𝑎𝑥 − 𝑀𝑎𝑥𝑖𝑚𝑢𝑚
𝑚𝑖𝑛 − 𝑀𝑖𝑛𝑖𝑚𝑢𝑚
𝑀𝐺 − 𝑀𝑖𝑐𝑟𝑜𝑔𝑟𝑖𝑑
𝑜𝑢𝑡 − 𝑂𝑢𝑡𝑝𝑢𝑡
𝑆𝑤𝑒𝑝𝑡 − 𝑆𝑤𝑒𝑝𝑡 𝑏𝑦 𝑡𝑢𝑟𝑏𝑖𝑛𝑒 𝑏𝑙𝑎𝑑𝑒𝑠
𝑊𝑇 − 𝑊𝑖𝑛𝑑 𝑇𝑢𝑟𝑏𝑖𝑛𝑒

29
6.0 Appendix
6.1 Figures
Figure 26: Full-scale proposed system diagram

30
Figure 27: Fiji power grid [3]

31
Figure 28: Number of cycles vs. depth of discharge for 12 CS 11P battery [22]
Figure 29: Average monthly wind speed distribution for sites in Fiji [5]

32

33
6.2 Sample Calculations
Wind Energy
The density of air is taken for standard conditions of a temperature of 25 C and pressure of 101
kPa and calculated using Engineering Equation Solver.
Maximum Wind Speed: 𝑉𝑚 𝑎𝑥 = 7.2
𝑚
𝑠
Minimum Wind Speed: 𝑉 𝑚𝑖𝑛 = 5.4
𝑚
𝑠
Maximum Wind Turbine Power Output: 𝑃 𝑊𝑇,𝑚𝑎𝑥 = 482.8 𝑊
Minimum Wind Turbine Power Output: 𝑃 𝑊𝑇,𝑚𝑖𝑛 = 178.1 𝑊
Swept Area: 𝐴 𝑠𝑤𝑒𝑝𝑡 = 7.1 𝑚2
Density of Air: 𝜌 𝑎𝑖𝑟 = 1.180
𝑘𝑔
𝑚3
Calculate the total power available in the wind assuming that the entire velocity is reduced to the
stagnation pressure [23] under maximum and minimum wind speeds.
𝑃 𝑤𝑖𝑛𝑑 = 𝑚̇ 𝐾𝐸 = (𝜌𝐴𝑉) (
1
2
𝑉2
) =
1
2
𝜌𝐴 𝑠𝑤𝑒𝑝𝑡 𝑉3
𝑃 𝑤𝑖𝑛𝑑,𝑚𝑎𝑥 =
1
2
(1.180
𝑘𝑔
𝑚3) (7.1 𝑚2) (7.2
𝑚
𝑠
)
3
≈ 1563 𝑊
𝑃 𝑤𝑖𝑛𝑑,𝑚𝑖𝑛 =
1
2
(1.180
𝑘𝑔
𝑚3) (7.1 𝑚2) (5.4
𝑚
𝑠
)
3
≈ 659.6 𝑊
Calculate the efficiency of the turbine under the maximum and minimum wind speeds observed.
𝜂 𝑊𝑇,𝑚𝑎𝑥 =
𝑃 𝑊𝑇,𝑚𝑎𝑥
𝑃 𝑤𝑖𝑛𝑑,𝑚𝑎𝑥
≈
(482.8 𝑊)
(1563 𝑊)
≈ 30.88%
𝜂 𝑊𝑇,𝑚𝑖𝑛 =
𝑃 𝑊𝑇,𝑚𝑖𝑛
𝑃 𝑤𝑖𝑛𝑑,𝑚𝑖𝑛
≈
(178.1 𝑊)
(659.6 𝑊)
≈ 27.00%
Microgrid Efficiency
Maximum Wind Turbine Power Output: 𝑃 𝑊𝑇,𝑚𝑎𝑥 = 482.8 𝑊
Charger Controller Efficiency: 𝜂 𝑐𝑐 = 0.95
Inverter Efficiency: 𝜂𝑖 = 0.97
The overall efficiency of the microgrid will include the charge controller and inverter efficiency
and assume that resistive losses are negligible.

34
𝜂 𝑀𝐺 = 𝜂 𝑐𝑐 𝜂𝑖 = (0.95)(0.97) = 0.921
Calculate the power lost for one wind turbine operating at maximum wind speed.
𝑃𝑜𝑢𝑡 = 𝜂 𝑜 𝑃 𝑊𝑇,𝑚𝑎𝑥 = (0.921)(482.8 𝑊) ≈ 444.9𝑊
Battery Bank Capacity
Battery Voltage: 𝑉𝑏𝑎𝑡𝑡 = 12 𝑉
Battery Capacity:𝐶 𝑏𝑎𝑡𝑡 = 357 𝐴ℎ
Number of Batteries Connected in Series: 𝑁𝑠 = 4
Number of Batteries Connected in Parallel: 𝑁𝑝 = 4
Rated Charge Controller Power: 𝑃𝑐𝑐 = 4000 𝑊
Rated Charge Controller Voltage: 𝑉𝑐 𝑐 = 380 𝑉
In series/parallel mode the battery bank voltage and capacity are increased by the number of
batteries connected in series and parallel respectively.
𝑉𝑏𝑎𝑛𝑘 = 𝑁𝑠 𝑉𝑏𝑎𝑡𝑡 = 4(12 𝑉) = 48 𝑉
𝐶 𝑏𝑎𝑛𝑘 = 𝑁𝑝 𝐶 𝑏𝑎𝑡𝑡 = 4(357 𝐴ℎ) = 1428 𝐴ℎ
It is recommended that the battery bank not be taken below 50% discharge. Therefore the actual
capacity is:
𝐶 𝑏𝑎𝑛𝑘
′
= 0.5𝐶 𝑏𝑎𝑡𝑡 = 714.0 𝐴ℎ
Calculate the rated current for the charge controller.
𝐼𝑐𝑐 =
𝑃𝑐𝑐
𝑉𝑐𝑐
=
(4000 𝑊)
(380 𝑉)
≈ 10.53 𝐴
Calculate the number of hours the battery bank can be run at half capacity.
𝑡 =
𝐶 𝑏𝑎𝑛𝑘
′
𝐼 𝑐𝑐
=
(714.0 𝐴ℎ)
(10.53 𝐴)
= 67.83 ℎ𝑟 ≈ 2.826 𝑑𝑎𝑦𝑠

35
6.3 EES Code and Results
"Set parameters"
T_turb= 92.2
p_turb= 2500
pcond= 600
eta_turb= .9
eta_pump= .8
W_dot = 9
"Inlet of turbine"
T[1]=T_turb
p[1]=p_turb
h[1]=enthalpy(R134A,T=T[1],P=p[1])
s[1]=entropy(R134A,T=T[1],P=p[1])
"Inlet of condenser"
s2s=s[1]
p[2]=pcond
h2s=enthalpy(R134A,S=s2s,P=p[2])
h[2]=h[1]-eta_turb*(h[1]-h2s)
T[2]=temperature(R134A,H=h[2],P=p[2])
s[2]=entropy(R134A,H=h[2],P=p[2])
x[2]=quality(R134A,H=h[2],P=p[2])
"Inlet of pump"
p[3]=p[2]
h[3]=enthalpy(R134A,P=p[3],X=0)
s[3]=entropy(R134A,P=p[3],X=0)
T[3]=temperature(R134A,P=p[3],X=0)
Tcond=T[3]
"Inlet of boiler"
s4s=s[3]
p[4]=p_turb
h4s=enthalpy(R134A,S=s4s,P=p[4])
h[4]=h[3]+(h4s-h[3])/eta_pump
T[4]=temperature(R134A,H=h[4],P=p[4])
s[4]=entropy(R134A,H=h[4],P=p[4])
s[5] = entropy(R134a, P=2500, X=0)
h[5] = enthalpy(R134a, P=2500, X=0)
T[5] = Temperature(R134a, P=2500, X=0)
p[5] = 2500
"Work and heat calculations"
wout=h[1]-h[2]
qout=h[2]-h[3]
win=h[4]-h[3]
qin=h[1]-h[4]
"Thermal efficiency"
eta_thermal=(wout-win)/qin
m_dot = W_dot/wout
T_H = 600+273.15
T_L = 193.2+273.15

36
Q_dot[1] =m_dot*h[1]
"Economic Analysis"
Monthly_demand = 6000 "kWh"
Desiel_cost = 0.73 "per litre"
Annual_desiel_usage = 23000 "litre"
Annual_operational_cost = Annual_desiel_usage * Desiel_cost
Cost_electricity = .331 "monthly usage over 95 kWh"
Cost_electricity2 = .172 "monthly usage less 95 kWh"
Annual_demand = Monthly_demand *12
Revenue_annual_1 = Cost_electricity * Annual_demand
Revenue_annual_2 = Cost_electricity2 * Annual_demand
Cost_ORC = 25000
Cost_Installation = 250000
Total_system_cost = Cost_ORC+Cost_installation
Payback_1 = Total_system_cost/Revenue_annual_1
Payback_2 = Total_system_cost/Revenue_annual_2
Figure 30: EES Results

37
References
[1] Central Intelligence Agency, "The World Factbook," 2016. [Online]. Available:
https://www.cia.gov/library/publications/the-world-factbook/geos/fj.html. [Accessed 6
April 2016].
[2] P. Nakavulevu, "Promoting Renewable Energy Policies in Fiji," 2015. [Online].
Available:
http://www.irena.org/DocumentDownloads/events/Workshop_Accelerated_Renewable_
Energy_Deployment/Session7/S7_2IRENA-RenewableEnergy-Fiji-Final.pdf. [Accessed
6 April 2016].
[3] International Renewable Energy Agency, "Fiji Renewables Readiness Assessment," June
2015. [Online]. Available:
http://www.irena.org/DocumentDownloads/Publications/IRENA_RRA_Fiji_2015.pdf.
[Accessed 6 April 2016].
[4] A. J. McCoy-West, S. Milicich, T. Robinson, G. Bignall and C. C. Harvey, "Geothermal
resources in the Pacific islands: The potential of power generation to benefit indigenous
communities," in Thirty-Sixth Workshop on Geothermal Reserovoir Engineering,
Stanford, 2011.
[5] A. Kumar and S. Prasad, "Examining wind quality and wind power prospects on Fiji
Islands," Renewable Energy, vol. 35, pp. 536-540, 2010.
[6] Marathon Generators, "Insulation System Thermal Life Expectancy vs Total Operating
Temperature," 2015.
[7] Leroy Somer, Emerson Industrial Automation, "Low Voltage Alternator - 4 Pole LSA
40," 2016.
[8] Pika Energy Ltd., "Pika Energy," 2015. [Online]. Available: http://www.pika-
energy.com/. [Accessed 16 November 2015].
[9] Fiji Meteorological Service, "Fiji Climate Summary 2016," February 2016. [Online].
Available: http://www.met.gov.fj/Summary1.pdf. [Accessed 7 April 2016].
[10] American Resource and Energy, "Vertical Gin Pole Wind Tower Raising System,"
[Online]. Available: http://www.arewindtowers.com/raising-systems/vertical-gin-pole.
[11] Northern Arizona Wind and Sun Solar Forum, "Series and Parallel Battery Wiring," May
2014. [Online]. Available: http://forum.solar-electric.com/discussion/22394/series-
parallel-battery-wiring. [Accessed 7 April 2016].
[12] Rolls Battery, "Deep Cycle Battery Catalog and Specs," 2016. [Online]. Available:
http://rollsbattery.com/catalog/. [Accessed 7 April 2016].
[13] P. C. Sen, Principles of Electric Machines and Power Electronics (3rd Edition),
Hoboken: John Wiley & Sons, 2014.

38
[14] Canadian Nuclear Safety Commission, "Sciene and Reactor Fundementals," Electrical
CNSC Technical Training Group.
[15] F. J. Matthew Dornan, "Electrical Generation in Fiji: Assessing the Impact of Renewable
Technologies on Costs and Finnacial Risk," in Australian Agricultural and Resource
Economics Society , Melbourne, 2011.
[16] J. M. K. S. J. D. Jordana Hanania, "Diesel generator," 28 March 2014. [Online].
Available: http://energyeducation.ca/encyclopedia/Diesel_generator. [Accessed 10 April
2016].
[17] Environment and Climate Change Canada, "Fuel Combustion," 21 June 2013. [Online].
Available: http://www.ec.gc.ca/ges-ghg/default.asp?lang=En&n=ac2b7641-1. [Accessed
8 April 2016].
[18] R. Rowshanzadeh, "Performance and cost evaluation of Organic Rankine Cycle at
different technologies," [Online]. Available: http://kth.diva-
portal.org/smash/get/diva2:410363/FULLTEXT01. [Accessed 9 4 2016].
[19] L. Shevenell, "The Estimated Costs as a Function of Depth of Geothermal Development
Wells Drilled in Nevada," GRC Transactions, vol. 36, pp. 121-128, 2012.
[20] Ray Solar, "Pika Energy — 3.7kW Hybrid Wind/Solar System," 2016. [Online].
Available: http://raysolar.ca/product/pika-energy-3-7kw-hybrid-windsolar-system/.
[21] Wholesale Solar, "Surrette / Rolls 12CS-11PS Flooded Battery," 2016. [Online].
Available: http://www.wholesalesolar.com/9900122/surrette-rolls/batteries/surrette-rolls-
12cs-11ps-flooded-battery. [Accessed 8 April 2016].
[22] Bergey Wind Power, "Small Wind Turbines for Homes & Businesses," 2012. [Online].
Available: http://bergey.com/wind-school/residential-wind-energy-systems. [Accessed 8
April 2016].
[23] B. R. Munson, T. H. Okiishi, W. W. Huebsch and A. P. Rothmayer, Fundamentals of
Fluid Mechanics (7th Edition), Hoboken: John Wiley & Sons, 2013.
[24] Maps of the World, "Fiji Map," [Online]. Available:
http://www.mapsofworld.com/fiji/maps/fiji-map.jpg. [Accessed 6 April 2016].
[25] National Renewable Energy Laboratory, "Distributed Generation Renewable Energy
Estimate of Costs," February 2016. [Online]. Available:
http://www.nrel.gov/analysis/tech_lcoe_re_cost_est.html. [Accessed 8 April 2016].
[26] VTU E-learning, "Design of Synchronous Machines".
[27] Marathon Generators, "Generators Selection and Pricing Catalog," Regal, Wausau, 2015.

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