MSc Renewable Energy Engineering: PV System Analysis and Evaluation

This report provides a comprehensive analysis and evaluation of a grid-connected photovoltaic (PV) system, based on data from the UCLan Media Factory. It begins with an introduction to solar energy and the factors influencing PV system design. The report then details the technical design of the system, including the specifications of the solar panels, inverters, and other components. It proceeds to analyze the system's performance using monitored data, evaluating parameters such as system efficiency, yield, solar irradiation, and performance ratio. The analysis includes the data from DC and AC sources, and the results are displayed in tables and charts. Furthermore, the report utilizes PVSYST simulation software to model the system and compare the simulation results with the data analysis. Finally, the report concludes by summarizing the findings and comparing the results obtained through data analysis and simulation.

PART A – Individual Work: Analysis and evaluation of a grid-connected photovoltaic (PV)
system
[Name]
[Course]
[Date]
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Table of Contents
Introduction............................................................................................................2
Task A: System Performance base on monitored Data................................................4
Technical Design of the System.............................................................................................4
Available Data Analysis.........................................................................................................5
Critical Evaluation of Data.....................................................................................................6
System Efficiency...............................................................................................................7
The System Yield................................................................................................................9
Solar Irradiation................................................................................................................10
Performance ratio..............................................................................................................10
Task B: System Simulation in PVSYST...................................................................11
PVSYST simulation of the Project.......................................................................................11
Conclusion............................................................................................................13
References............................................................................................................14
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Introduction
With the cost of energy increasing and the other sources of electric generation,
traditional ones, being depleted, these factors coupled by the fact that the cost of living is on
the rise, solar energy has become a suitable way of generating electricity in households and
corporates. The fact that solar energy is inexhaustible, there’s abundance of it, and is a non-
pollutant the solar generation way is better that the other ways of electricity generation. In the
UK there’s a good solar radiation throughout the year, though the winter usually gets has a
lower solar radiation, but it is enough to generate electricity for even an average commercial
premise. Solar panel generation can only be a successful way of electricity generation, when
it is well designed, which follows a good installation. When designing a solar PV generation
plant, be it domestic or for commercial purposes, there are some factors that must be
considered like: the efficiency of the sunshine hours, the space for installation, the purpose
for the solar (what the power will be used for), the financial capability of the person installing
the solar PV, the angle of inclination of the solar PV panels, the type of the solar PV panels,
among other factors.
A solar plant usually has two sides, the direct current (DC) and the alternating
current (AC) of the plant. These designs are usually different because they have different
devices used in the installation of each of the sides. The installation of the DC side of the
plant, depends on the type of devices that shall be used, whether parallel or series connection.
When PV connection is in series the DC side of the PV plant, the total Maximum Power
Points (MPP) is more than the inverter Min MPP voltage. Total open-circuit voltage at a
minimum module temperature is less that the inverter at maximum voltage. When PV
connection is in parallel, the maximum current shall be less than or equal to maximum input
current of the inverter, the number of the combiner boxes of the arrays, whether the
monitoring base is available or not, are equal to the number of inverter inputs. The AC side of
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the plant design must have: the AC side cables, Low Tension (LT) switchgear and Mega
voltage switchgear, the power transformers (LV to MV), the High Tensions (HT) switchyard,
metering and protection and the transmission lines.
Based on the drawings provided and the data provided, the aim of the this paper is
to analyse the performance of the PV system in excel where there are entered data, it also
focuses on the simulation tool called PVSYST to evaluate the details of the project and
compare the results with the analysed. The data provided are for a solar
Task A: System Performance base on monitored Data
Technical Design of the System
The solar panels are slated to be on a roof top, inclined at a particular angle to
focus on the sunlight. The angle of inclination shall be around 10o on the rooftop as earlier
indicated and shall cover an area of 283 m2. The solar PV are arranged in 18 strings, meaning
that there are 12 modules connected in parallel, with every array having three of the panels.
The solar panel used shall have a power of 180W, manufactured from a company called
Sharp electronics company written as NU180E1, this shows the power in watts produced per
solar panel and they are of the monocrystalline model. An array will have 36 panels and with
six arrays means the total shall be 216 panels which further means there shall be six inverters
having a parallel connection with the panels. The system shall have monocrystalline as
indicated earlier, which suits the system. As it is known, monocrystalline is efficient (Sendy,
2020).
Once the array has been established and connected, the next connection shall be
the junction boxes for the arrays, where there are DC component connection for the solar PV
system. This part is responsible for power division that goes to the various circuits, it also
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protects the circuits that feeds each circuit. In addition, it also controls the DC coming from
the solar panels which further are reinforced with surge protection them (Pickerel, 2017).
Figure 1: Solar PV on the rooftop for the UCLan Media Factory
Available Data Analysis
During the installation of the solar panels, a technician must take into
consideration the isolation, that is where the DC isolator switch is important. The isolation
takes place during maintenance of the system’s PV array. On the other hand, AC isolators are
also installed in this system, the DC isolates the DC power and the AC isolates the AC power
(Thornean & Derrick , 2014). The project used 32A rated isolators that were sufficient to do
the job. Now an isolator come in after the inverter, AC isolators, these are used for inverter
isolation, since it inverts the DC to AC, now the AC side has an isolator, which are lockable.
Now from here the power that comes from inverters, through the isolator, can now be used in
the indistinctive, resistive or the capacitive loads (RLC loads). In this project, there shall be a
use of string inverters, which are the centralized inverters, also are the power optimizers
(EnergySage, 2020).
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Another part of the system is the low voltage (LV) board, this is where the RLC
etc loads get connected from or draw their power from. The circuits are connected through
the MCCBs which connects the loads. The appropriate system for this is one of a rating of
225A mains and connected to a cable of 120 mm which has 4 cores, PVC armoured cables,
the main isolator shall be 1600 A MCCB.
The available data provided about the solar plant are shown in the figure 2 which
shows the parameters that the solar plant operates and the type of solar panel that will be in
use.
Figure 2: Available data of the Solar plant installed at the roof of the Media Factory, Preston
Campus
Critical Evaluation of Data
This section, there shall be an analysis of the performance of the system in terms
of the power produced and the power output. The performance of the system shall be
evaluated when the DC and AC or the power generated and the output power respectively are
compared to each other and efficiency achieved. So, the available data were summarised in
months are the table1 and 2.
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System Efficiency
Table 1: The generated voltage from the DC source in the year 2013
Months Voltage DC
MPP1|IG
60(1) (# 1)
Voltage DC
MPP1|IG
60(2) (# 2)
Voltage DC
MPP1|IG
60(3) (# 3)
Voltage DC
MPP1|IG
60(4) (# 4)
Voltage DC
MPP1|IG
60(5) (# 5)
Voltage DC
MPP1|IG
60(6) (# 6)
Jan 240125 237465 244518 239451 242001 242379
Feb 291926 286998 293430 289007 292471 291375
Mar 400598 400296 404916 401187 400330 397621
Apr 457513 456607 460031 454603 456187 451586
May 523065 584678 525381 523380 524963 523035
Jun 523561 525497 526510 522291 523001 522108
Jul 514970 533301 517252 510086 514646 510382
Aug 472828 491287 476193 474994 477308 473572
Sep 391170 390400 394180 392723 393300 389855
Oct 331590 330043 333738 332237 333399 331318
Nov 260617 252334 260746 256905 261371 256755
Dec 228159 221607 225538 221473 229131 222269
The data obtained here are the data from the solar PV installed at the roof top. This is directly
proportional to the solar radiation, since it is the input at the same time it is dependent on the
solar produced. The data were recorded from the power that were going in the inverters
before they were inverted. The table 2 are data from the AC source, this means they are the
output data meaning they are generated after their conversion from the DC power. This is the
power that goes to the useful loads. Between May and August remains the hottest months in
Preston. It is from this that efficiency is obtained, see Table 3
Table 2: The generated voltage from the AC source in the year 2013
Months Voltage
AC L1|IG
60(1) (# 1)
Voltage
AC L1|IG
60(2) (# 2)
Voltage
AC L1|IG
60(3) (# 3)
Voltage
AC L1|IG
60(4) (# 4)
Voltage
AC L1|IG
60(5) (# 5)
Voltage
AC L1|IG
60(6) (# 6)
Jan 202832 201942 202115 201415 207261 206659
Feb 241979 242637 242217 240867 244650 243327
Mar 327969 327483 326717 325939 330311 328963
Apr 382422 382012 381966 380297 385582 384519
May 446074 204075 445575 444435 450572 448744
Jun 456187 456239 455741 453791 459534 458171
Jul 462489 399895 462195 459785 465563 463646
Aug 412322 337184 411789 410241 416361 414741
Sep 337850 337993 337259 336606 341254 340061
Oct 283793 283317 282257 280640 285679 285211
Nov 222605 223540 223919 223154 226338 225238
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Dec 192893 192509 193912 192019 195902 193574
Chart 1: The chart showing the plotted data obtained from the DC readings of the solar
Chart 2: The chart showing the plotted data obtained from the AC readings of the solar
Table 3: Table showing the system efficiency
Voltage DC 4,636,122.00 4,710,513.00 4,662,433.00 4,618,337.00 4,648,108.00 4,612,255.00
Voltage AC 3,969,415.00 3,588,826.00 3,965,662.00 3,949,189.00 4,009,007.00 3,992,854.00
Efficiency 0.8562 0.7619 0.8506 0.8551 0.8625 0.8657
The average of the system is 0.84 or 84%, which shows that that the system is efficient.
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The System Yield
Months
Sum of
Specific
yield|IG
60(1) (# 1)
Sum of
Specific
yield|IG
60(2) (# 2)
Sum of
Specific
yield|IG
60(3) (# 3)
Sum of
Specific
yield|IG
60(4) (# 4)
Sum of
Specific
yield|IG
60(5) (# 5)
Sum of
Specific
yield|IG
60(6) (# 6)
Jan 11.61 10.71 11.78 11.19 10.99 12.06
Feb 34 31.27 34.45 32.03 31.98 33.88
Mar 68.92 66.87 68.02 63.02 63.47 64.36
Apr 105.81 103.95 104.1 97.31 97.87 98.47
May 118.31 58.7 113.79 107.52 111.59 110.42
Jun 131.82 132.48 127.39 120.03 124.34 122.58
Jul 147.7 130.3 142.68 134.2 138.07 136.99
Aug 105.4 84.75 102.6 97.66 100.18 100.35
Sep 65.07 63.12 64.5 60.84 61.85 62.48
Oct 36.06 34.28 36.11 34.14 34.6 35.37
Nov 19.84 17.96 20.26 19.18 18.06 20.78
Dec 8.91 8.71 9.48 9.07 8.64 10.24
The system yield shows the much power the system is able to give, which is also related to
the power the system is able to obtain from the environment. Which again is consistent with
the solar power the system can get from surrounding, with July recording the highest in yield,
at the same time it records the same with the power output and input.
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Solar Irradiation
Months Irradiation
Jan 75037.24
Feb 173167.28
Mar 294073.7
Apr 451153.73
May 501708.86
Jun 570911.22
Jul 660158.61
Aug 464419.32
Sep 291418.66
Oct 175238.24
Nov 127555.38
Dec 73375.88
Grand Total 3,858,218.12
Chart 3: Solar Irradiation chart
Performance ratio
The formula for obtaining the performance ratio (PR) is
Where: A is the total panel area in m2, r is the solar panel yield efficiency, and H is the solar
insolation on the tilted panels (kWh/m2).
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Task B: System Simulation in PVSYST
PVSYST simulation of the Project
The first thing is to establish the area at a google map, then finding the azimuth,
that shows the sun path of the area under study. Remembering that the tilt angle was 10o, we
can not find the irradiation and other elements. The results are therefore obtained as shown in
the screenshots.
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