ISSN:1390-9266 e-ISSN:1390-9134 LAJC 2024
82
DOI:
LATIN-AMERICAN JOURNAL OF COMPUTING (LAJC), Vol XI, Issue 2, July 2024
10.5281/zenodo.12192271
B. da S. Macêdo, C. M. Saporetti,
“Electricity Energy Demand Prediction Using Computational Intelligence Techniques”,
Latin-American Journal of Computing (LAJC), vol. 11, no. 2, 2024.
the energy sector, selecting the forecasting model and
approach for demand prediction is a crucial decision.
Companies operating in the energy sector can set their
strategic goals and have the opportunity to improve
performance based on this study.
The present study is divided into five sections: section 2
presents the research related to this study. Section 3 discusses
the study area, as well as the methodology used. In section 4,
there is a discussion of the results obtained and, finally, in
section 5, the conclusions of this study are presented.
II. RELATED
RESEARCHES
Forecasting energy demand in Brazil is a topic that has
been studied by many researchers. In these studies, analysis is
carried out and it is proposed tools in the context of Data
Mining to understand the problem and seek solutions to
predict the results.
Ruas et al. [5] carried out a study on predicting short-
term energy demand in the state of Paraná between 2004 and
2006. Artificial Intelligence methods were used to predict the
results, such as Recurrent Artificial Neural Networks (RNNs)
and Support Vector Machine (SVM). The SVM algorithm,
with 84 days of input, with sub-bands for the forecast, was the
one that obtained the best result.
Alves [6] conducted a study on short-term electrical load
forecasting, with historical data from periods of 24 and 48
hours forward, from a company in the electrical sector.
Multiple Linear Regression (MLR) and Multilayer Perceptron
(MLP) algorithms were used. The MLP was the one that
achieved the optimal results.
In the research by Drebes [7], the energy demand for a
given day was forecast for the Certel Cooperativa Operations
Center Company, responsible for the operation of distribution
systems, operation of substations and responsible for
controlling active demand. The algorithms used were the
MLP, Linear Regression (LR) and Random Forest (RF). The
LR algorithm was the one that presented really good results.
Schreiber et al. [8] made a prediction of the performance
of transformers at the State Electricity Distribution Company
in the city of Porto Alegre, Rio Grande do Sul. The MLR
algorithm was used. The best results showed an average
relative error of 0.050 of the real and estimated yield.
In Marcos and Júnior’s work [1], machine learning
techniques were used to predict electricity consumption in the
Northeast region of Brazil, between the years 2004 and 2019.
MLP and Convolutional Neural Networks (CNN) were those
that obtained the best outcomes.
Oliveira [9] used the GWO meta-heuristic to minimize the
objective function total cost of a shell and tube heat exchanger
project, which are used to heating and cooling in various
applications such as petroleum refineries, chemical
processing, among other applications.
In Pizzolato et al. [10], the GWO meta-heuristic was used
to obtain the optimal configuration of relay actuation and
optimize relay time, which allows faults to be identified, locate
and alert the operation of an electrical system so that circuit
breakers are open, isolating a given defect. Using GWO, it was
possible to coordinate the relays, maintaining the adjustments
to the protection system.
The papers found do not forecast energy demand for Brazil
as a whole, but rather for specific regions, in addition to not
using approaches to find the optimal model. The application
of machine learning algorithms is very promising and
employing meta-heuristics will help to find the best model,
making it possible to predict demand with less error.
III. METHODOLOGY
A. Database
The National Electric System Operator (ONS) has diverse
information about energy in Brazil. In this study, the variable
Energy Load (EL) was used, which indicates the population's
demand, that is, how much energy is used.
The database has daily records of the energy load across
the country, where this information is separated by regions. As
the objective is to analyze the entire country, a sum of
information from all regions was carried out to obtain the
demand of the Brazilian population as a whole. The period
used for predictions is between the years 2017 and 2022,
around 8,764 samples.
B. Pre-Processing
There are four attributes available: id_subsistema,
nom_subsistema, din_instante and val_cargaenergiamwmed.
The id_subsistema attribute contains the initial letter of each
region of Brazil. For example, for the North region the
representation is N. The nom_subsistema attribute represents
the name of the regions of Brazil, being North, South,
Southeast and Northeast. Information for the Central-West
region is not available on the base. Furthermore, the
din_instante attribute indicates a respective date, in the format
(YYYY-MM-DD). Finally, the val_cargaenergiamwmed
attribute presents the load value in milliwatts (MW).
To predict energy demand, only the variables din_instante
and val_cargaenergiamwmed were considered. They were
renamed to DATE and EL, respectively. The DATE variable
represents a single date and the EL variable represents the sum
of energy loads between the North, South, Southeast/Central-
West and Northeast regions. After summing up the energy
load of the regions, the database had 2,191 samples.
Furthermore, a normalization of the EL variable was
performed, resulting in values from 0.10 to 0.90. The attributes
that refer to the energy load value of each region, as well as
those that identify a specific region, were excluded, as the
DATE and EL attributes, which contain the sum of the loads
between the regions, will be taken into consideration for the
analysis. A lag was also created in the database, creating 7
variables: EL1, EL2, EL3, EL4, EL5, EL6 and EL7. EL1 has
a charge from the second day of EL and as it contains one less
piece of information, this remains as NaN. EL2, from the third
day onwards, contains two NaN information and so on. These
samples containing NaN were excluded, 7 in total. After
exclusion, 2,184 samples were obtained. This way, it will be
possible to predict the energy load for the eighth day
considering the previous seven. With the creation of these
variables, a new base was created, having only the following