Content uploaded by Harikrishnan Ramachandran

Author content

All content in this area was uploaded by Harikrishnan Ramachandran on Apr 25, 2022

Content may be subject to copyright.

1

Implementation of Tilt angle computing in IoT

Based PV System

Sivagami.P1, Meet Mehta1, Abhijeet Kumar1, Harikrishnan. R2, Pushpavalli.M1 and Abirami.P3

1Dept. of EEE, Sathyabama Institute Of Science &Technology, Chennai,India

2Symbiosis Institute Of Technology, Symbiosis International Deemed University, Pune,India

3Dept. of EEE, B. S. Abdur Rahman Crescent Institute of Science & Technology, Chennai,India

E-mail : sivagamitec@gmail.com mehtameet018@gmail.com abhi009krlal@gmail.com rhareish@gmail.com

pushpa.murugan@gmail.com, abiramiramkumar@gmail.com

Abstract- Because of depleting energy resources, to increase

the reliability as well to reduce the capital expenses

innovation has to be made to increase the power output from

renewable energy. In order to meet the energy demand in

future among the energy sources one of the propitious

energy source is solar energy. The energy from the sun is

abundant and is radiated on the earth surface in the form

of heat and light. Some of the alterable factors which

influence the production of electric power from solar energy

are PV installation factors namely the angle of incidence of

light from the sun, orientation, area of exposure etc. The

factors that cannot be altered are ambient temperature,

wind movements, solar insolation etc. Since the earth and

the sun position differs for the month and season. Due to this

PV panel tilt angle as well as absorption of sunlight vary.

Thus, the energy generation can be increased by

determining the optimum angle for PV panel to collect

maximum amount of solar energy to increase the electrical

energy generation. Thus, tilt angle decides the PV panel

surface area exposed to the solar radiations. If the yearly

average fixed tilt angle is used the loss of energy is around 8-

10% for each month. In order to increase the efficiency, the

tilt angle should be varied. This paper confers about the

factors influencing the tilt angle, determination of tilt angle

and and also about IoT-Internet of Things integrated smart

methodology for varying the value of tilt angle for PV panel

to extract maximum energy to make PV more efficient and

reliable.

Keywords: Solar irradiation; Photovoltaic system-PV

system; tilt angle

I.INTRODUCTION

One of the most widely used energies in producing

electricity is fossil fuels. But in recent years the

contribution made by non - fossil fuel gradually

increases. Because of depletion of fossil fuels the

consumption will decay by time but solar energy is

renewable and it depends on the sun that is it will not

vanish or run out like fossil fuel. Fossil fuel causes

land degradation, water pollution, emits harmful

gases. The emission of harmful gases like carbon

dioxide causes increase in temperature which results

in global warming but solar produces clean energy.

The cost of energy produced using fossil fuel is

expensive when compared to energy produced using

solar. In conventional fossil fuel forecast fossil fuel

energy consumption increases till 2020 after that its

consumption decreases. The power produced using

fossil fuel cost around .05$/kwh whereas solar cost

around 0.029$/kwh. The implementation of solar

photovoltaic system helps in producing electric

power. The electric power produced can be sold that

is it provides an income for the investor or owner of

the solar plant. Since it helps in earning it is

important in economic point of view. Thus, solar

photovoltaic system gains importance in this era not

only because of energy point of view but also

economic point of view. The figure 1 represents the

conventional fossil fuel rise and fall for the period of

1900-2100. The figure 2 delineates the contribution

of fossil fuel for the year 2018-2020. It becomes

essential to harness maximum yield from solar.

Solar power generation is dependent on

environmental parameters namely solar insolation,

ambient temperature, temperature of the PV panel,

speed and direction of wind, tilt angle etc. Tilt angle

also play a vital role in harnessing maximum energy

from PV panel. There are different methodologies

available to determine the tilt angle. They are using

direct, diffuse and reflection components of radiation

or by involving components either dependent or

independent on atmospheric condition namely

isotropic and anisotropic. In IDR- Isotropic Diffused

Radiation model diffused radiation intensity of sky is

assumed to be uniform [11]. In NADR- Anisotropic

Diffused Radiation model for tilted surface it

includes circum solar diffused radiation and horizon

brightening component [12]. PV calculator

determines the output power from PV panel by

varying the value of tilt angle. The equation for

optimal angle is based on latitude [13]. Manually tilt

2022 International Conference on Advances in Computing, Communication and Applied Informatics (ACCAI) | 978-1-6654-9529-5/22/$31.00 ©2022 IEEE | DOI: 10.1109/ACCAI53970.2022.9752532

Authorized licensed use limited to: Sathyabama Institute of Science and Technology. Downloaded on April 21,2022 at 08:10:29 UTC from IEEE Xplore. Restrictions apply.

2

angle is adjusted. The power output is determined for

various tilt angles [14]. MAT lab code also helps us

in determine the tilt angle based influenced by solar

radiation [15]. Some of the papers here discussed

about the methodology in calculating the tilt angle

and few other papers here delineate the importance of

tilt angle for harnessing maximum energy.

The energy generation increased by 10.54% for

latitude of 41°and longitude of 20° for Barcelonia

city in Spain. In winter it has 56.4°, for spring season

it is found to be 29.11°, summer 13.76° and for

autumn 48.14° [1]. By examining the factors namely

latitude, solar insolation, covering areas, the optimal

tilt angle is determined for rooftop PV installed at

Jilin Electric power Research Institute and is found

that tile mode improves the power generation for

fixed area [2]. For winter season PV module with

higher tilt angle harness maximum energy and

reduces the cost by 25% when compared to that of

the traditional approach [3]. The optimum tilt angle is

used to determine the gain in terms of power output

and current intensity [4]. C programming

implemented to determine the yearly average tilt

angle [5]. The output obtained from thermal energy

conversion increases when solar thermal collectors

tilted at 40°. The result determined by considering

sunny day, cloudy day and an interemediate between

sunny and cloudy day that is for 3 different types of

days [6]. In main cities of Palestinian, solar panels

installed yielded 17% more power when angle

adjusted monthly. For seasonal and semiannual

adjustment, it generates 15% more. The yearly

average angle which yields 10% more is 29° for

Palestinian cities [7]. Particle Swarm Optimization

estimator developed to determine the value of tilt

angle to get maximum solar energy. The optimized

angle value determined using this method is

validated with analytical results and the outcome of

this method is found to be satisfactory [8]. Different

angle values are determined using regression analysis

for various months. For Jan-March the angle value is

found to be 32°, April-June it is 25°, July -September

its value is low and is 15° and for October-November

again it increases and is 37°, for the panels laced. in

Chandigarh location [9]. The voltage profile

determined for varying tilt angles and found that

34.5° yields maximum power for rooftop solar panels

in Belgium [10].

Fig. 1 Forecast of conventional fossil fuel

consumption [Europe.oidrum.com]

Fig. 2 Contribution of fossil fuel and non- fossil

fuel

FACTORS INFLUENCING TILT ANGLE

Solar radiation means solar power from sun received

per unit area in the form of electromagnetic radiation

in (W/m2), whereas integration of solar radiation for

a given time period is solar irradiation and it is given

in kWh/m2 or J/m2. The figure 3 delineates the

increase in radiation from 6 am and reaches peak at

12.pm and gradually decreases from 12pm to 6pm

and also solar radiation and irradiation. Solar

irradiation may be direct horizontal, diffusion

horizontal, global horizontal or global tilted. If the

radiation moves through the atmosphere without

being scattered, reflected or absorbed by particles in

air is direct horizontal whereas the inverse of it is

diffusion horizontal. Global horizontal is the sum of

direct and diffusion radiation received from sun by a

horizontal surface and is denoted by SH. Global

horizontal irradiation differs for each location. Global

Authorized licensed use limited to: Sathyabama Institute of Science and Technology. Downloaded on April 21,2022 at 08:10:29 UTC from IEEE Xplore. Restrictions apply.

3

tilted irradiation received by tilted surface from sun

is the contibution of direct and diffused radiation and

is represented as Sm. Sm mean the total number of

hours the panel is exposed to solar radiation. It is

expressed in term of SH, alpha and beta. Alpha(α)

represents the angle between ground level and

incident rays whereas beta(β) is the angle obtained

between the solar panel and horizontal plane.

Fig. 3 Variation in solar radiation received during

day

The number of solar hours determine the electric

power generation. If the number of solar hours is

more then, the power generated is also more. PV

panel has to be adjusted to particular tilt angle value

to harness maximum output. Tilt angle is influenced

by declination angle(δ) and elevation angle(α). When

the earth is moving it tilts with an angle, this angle

between earth axis and universe axis is called

declination angle. As the earth rotates the declination

angle changes that is the universe axis is constant but

the earth axis varies. When the earth axis is exactly

aligned with universe axis the declination angle is

zero. Zero declination angle causes spring climate on

the earth. During this period day hours equals night

hours. This happens exactly on 21st of march. When

the earth moves around and makes a quarter cycle the

declination angle increases in step from zero to its

maximum value 23.5 degree exactly on 21st of July.

During this period day hours is greater than night

hours and it causes summer on earth. When the earth

completes half cycle the declination angle starts to

decrease until it reaches zero. At this position again

angle becomes zero and the earth experiences

autumn climate. It reaches zero on 21st of

September. Again, when earth rotates for new quarter

cycle the declination angle again increases from zero

to 23.5 degree in opposite direction so its value

become negative that is -23.5 degree on 21st

December where night hours is more compared to

that of day hours. So, the earth’s surface become cold

during the winter season. During new quarter cycle

again, the angle decreases from maximum to zero as

a result the spring season starts and the cycle repeats.

Hence the declination angle may have the values [-

23.5,23.5]. The figure 4 shows the outpower yield for

declination angle.

Declination angle is determined using following

expression

360

= 23.5 Sin( (284 )) 1

365 d

Where d delineates the day number of the year. For

example, let us consider the 12th day of February.

For this corresponding date the day no of the year is

43 therefore the value of d is 43. Substituting the

value in the expression declination angle is

determined. The figure 5 shows the day number for

the corresponding month in a year.

360

= 23.5 Sin( (284 43)) 2

365

( 14.29 )

Fig. 4 Influence of declination angle on output

power

Elevation angle values varies between 0° to 90° and

is given by the expression

α=90°-ψ+δ 3

Where Ψ represents the latitude of the location.

The tilt angle β is determined using the expression

β=90-α 4

Some standard values of β are 15°, 20°, 25°,

30°,45°, 60°.

III .EXCEL SOFTWARE PROGRAM TO DETERMINE

THE TILT ANGLE

An excel program designed to calculate the peak sun

hours and tilt angle required to harvest maximum

energy. The steps involved in it are as follows.

Step 1:Getting the information about latitude and

longitude of the location where solar panel has to be

Authorized licensed use limited to: Sathyabama Institute of Science and Technology. Downloaded on April 21,2022 at 08:10:29 UTC from IEEE Xplore. Restrictions apply.

4

installed.

Step 2: Getting the tilt angle beta.

Step 3: Getting peak sun hour value.

Since we know that Sm dependable parameters.

If Sm(max)- Sm(min)> 2 hours then Sm= Sm(min)

else Sm= ∑ Sm/12.

The data about insolation incident on a Horizontal

Surface (kW-hr/m^2/day) is obtained from the

website https://power.larc.nasa.gov/. The power

access viewer helps in providing the value of SH for

any latitude and longitude. The figure 6 shows the

steps involved in getting value of SH. By selecting

particular location and for different time period solar

insolation on a horizontal surface can be

downloaded as ASCII, CSV, GeoJSON, NetCDF

file format. Once determined the value from the

website substitute that in excel program to determine

the value of tilt angle. The figure 7 represents the

data received in CSV format from the website. The

figure 8 shows the solar insolation value from 2000-

2019. The figure 9 shows the solar insolation level

for the period of December to February.

Accordingly, the optimal angle is calculated using

the excel sheet and is found that for Chennai

location in India the tilt angle is 30°and 15°. The

figure 10 shows the tilt angle for various months.

Fig. 5 Day number for a month in a year

IV . SIMULATED OUTPUT VERSUS

THEORETICALLY DETERMINED OUTPUT

Theoretically determined value is validated by

PVSOL simulation software. Tilt angle calculation

dated 4th March 2021 (63rd day as per the above

data)

Substituting 63 in place of d as day number, we get,

after calculating, Value of declination angle (δ) as -

7.16° Elevation angle (α) = 90-ψ + δ ; where ψ is

latitude of the Semmancheri ( Chennai) (i.e. 13°).α =

69.09°

Tilt angle β = 90- α = 20.91°

The figure 12and 13 shows the mean capacity,

monthly capacity factor and data set respectively.

After the Above case study for solar irradiation and

power generation using the total available sunshine

hours in Chennai. We have plotted graphs and

calculated the desired tilt angle for obtaining

maximum output from an installed capacity of 1.2

KW solar. By analysing tilt angle for the

abovementioned system as 21.5 degrees, we have

found that the generating capacity is at peak during

the months of November, December, January,

February, March and April by constituting about

65% of generation in this 6 month.

Fig. 6 Delineates the step to get the value of SH

5

IV . IOT FOR ADJUSTING THE TILT ANGLE

In order to optimize the PV output, the solar panel

must face the sunlight directly. The optimized PV

output for the year round is obtained by tilting the

panel at that particular location latitude. Tilt angle

information can be stored in the cloud portal.

According to the seasonal variations this information

is processed and stepper motor can be used to vary

the value of the tilt angle of the panel to harness

maximum yield.

Fig. 7 Website provided data in CSV format

The proffered PV farm automation installation using

cloud approach provides monitoring as well as

controlling over the internet securely from any place

without the need of hardware, large memory. Smart

PV system can be established with cloud setup. The

cloud provides lots of services. It provides large

memory for storing data. The stored data can be

processed and retrieved for analysis from the cloud.

In this system cloud processed data sends a

command to controller unit to perform the action

using Wi-Fi. The figure 14 delineates smart control.

Fig. 8 Solar insolation value for Chennai location for

period from 2000-2019

Fig. 9 Solar insolation value for Chennai location for

period from dec 2019-Feb 2020

Fig. 10 Tilt angle for Chennai location.

0

5

10

15

20

25

30

35

TILT ANGLE

MONTH

6

Fig. 11 Delineating daily mean and monthly

capacity factor

Fig. 12 Delineating dataset

Fig. 13 Web based tilt angle adjustment using

stepper motor

7

Fig. 14 Excel program showing the tilt angle

calculated for the month of march

V . CONCLUSION

Tilt angle value differs for each month when

calculated using the excel program. It was found that

for the month of December-36°, January-34° and for

the month of February- 27°. Therefore, for values

less than 22° the angle opted is 15° and for 22° - 36°

the angle opted is 30°. Similarly, for greater than 36°

and less than 52° the angle opted is 45° and for

greater than 52° the optimal tilt angle value is 60°.

For collection of maximum radiation for energy

conversion from the sun optimal tilt angle for each

month can be considered.The tilt angle Dec-Feb is

30°, March-September is 15° and for October-

November is 30° for Chennai location in India. The

yearly average tilt angle for the panel is 21.5°. The

tilt angle is made fixed in some cases to keep the

manufacturing and installation cost low. For

enhanced efficiency if tilt angle is not varied for

month at the least it has to be varied for seasons. As

extension of this methodology, IoT integrated

tracking systems that adjusts automatically the tilt

angle if implemented increases the power output and

also improves the efficiency. Thus, IoT implemented

renewable energy sector becomes smarter, more

efficient in improving the performance, reliability

and in extracting & distributing maximum energy

harnessed.

REFERENCES

[1] Z. R. Dogaheh and V. Puig, "Tilt Angle Optimization of

Photovoltaic Panels," 2019 6th International Conference on

Control, Decision and Information Technologies (CoDIT),

Paris, France, 2019, pp. 1847-1852,

doi:10.1109/CoDIT.2019.8820549

[2] H. Liu, X. Xu, Y. Meng, D. Yu, H. Liu and K. Shi, "A Research

for the Influence of Tilt Angles of the Solar Panel on

Photovoltaic Power Generation," 2018 International Conference

on Smart Grid and Clean Energy Technologies (ICSGCE),

Kajang, 2018, pp. 95-100, doi: 10.1109/ICSGCE.2018.8556655.

[3] A. J. Swart,"Visualising the effect of different tilt angles on the

switch-on time of small PV modules using a simplified

measuring approach”, 2017 IEEE AFRCON Cape Town.

Pp.1014-1019

[4] D. Machidon, R. Oprea and M. Istrate, "Power Output

Experimental Evaluation of Fixed Photovoltaic Systems when

using Adjustable Tilt Angles," 2019 International Conference

on Electromechanical and Energy Systems (SIELMEN),

Craiova, Romania, 2019, pp. 1-4, doi:

10.1109/SIELMEN.2019.8905822.

[5] Zhang Guofang, Bai Jianbo and Cao Yang, "Analysis and

optimization of tilt angle for photovoltaic arrays," 2016 IEEE

International Conference on Power and Renewable Energy

(ICPRE), Shanghai, 2016, pp. 542-546

[6] A. Cotorcea, A. Pocora, F. Nicolae, I. Visa and M. Moldovan,

"Experimental Assessment of The Tilt Angle Influence on The

Solar Thermal Collectors Performance," 2020 7th International

Conference on Energy Efficiency and Agricultural Engineering

(EE&AE), Ruse, 2020, pp. 1-6, doi:

10.1109/EEAE49144.2020.9278970.

[7] Abdallah, R., Juaidi, A., Abdel-Fattah, S., & Manzano-

Agugliaro, F. (2020). Estimating the Optimum Tilt Angles for

South-Facing Surfaces in Palestine. Energies, 13(3), 623.

doi:10.3390/en13030623

8

[8] Sahu, Sanjaya Kumar and Tripathi, Nagendra and Tripathi,

Supriya, A Model Driven Optimization Approach to Determine

Tilt Angle of Solar Collector in India (February 11, 2020).

International Journal of Advanced Research in Engineering and

Technology, 10(2), 2019, pp. 431-448.

[9] Sharma, M. K., Kumar, D., Dhundhara, S., Gaur, D., & Verma,

Y. P. (2020) “ Optimal Tilt Angle Determination for PV Panels

Using Real Time Data Acquisition Global Challenges.

doi:10.1002/gch2.201900109 .

[10] Laveyne, J. I., Bozalakov, D., Van Eetvelde, G., & Vandevelde,

L. (2020). Impact of Solar Panel Orientation on the Integration

of Solar Energy in Low-Voltage Distribution Grids.

International Journal of Photoenergy, 2020, 1–13.

doi:10.1155/2020/2412780.

[11] Jhumoor Biswas, Arindam Dutta, Subhasis Neog, Soma

Roychowdhury,“ Optimum Tilt Angles for Manual Tracking

of Photovoltaic Modules”, Energy J. 2016.

[12] N Bailek, K Bouchouicha, N Aoun, M EL-Shimy, B Jamil, A

Mostafaeipo, “Optimized fixed tilt for incident solar energy

maximization on flat surfaces located in the Algerian Big

South”, Sustainable Energy Technologies and Assessments 28,

96-102

[13] Mark Z. Jacobson, Vijaysinh Jadhav, “World estimates of PV

optimal tilt angles and ratios of sunlight incident upon tilted and

tracked PV panels relative to horizontal panels”, Solar Energy

2018.

[14] Metin Kesler,Harun Ozbay, Akif Karafil, Yasemin Onal,

Huseyin Parmaksiz, Energy Procedia 2017, “The monitoring of

monthly, seasonal and yearly optimum tilt angles by Raspberry

Pi card for Bilecik city, Turkey”.

[15] MAM Ramli, YA Al-Turk, TO Kaddouraa, “On the Estimation

of the Optimum Tilt Angle of PV Panel in Saudi Arabia”,

Renewable and Sustainable Energy Reviews 65, 626–634