Update README.md

README.md

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+# Dataset Card for ONS-Capacity-Factor-Dataset
+
+## Dataset Summary
+
+The **ONS-Capacity-Factor-Dataset** provides hourly capacity factor data for wind and solar power plants in Brazil. These values are published by the **Operador Nacional do Sistema Elétrico (ONS)** — the Brazilian National Electric System Operator — which is responsible for coordinating and controlling electricity generation and transmission in the National Interconnected System (SIN).
+
+The dataset includes data from **2009 to 2025**, with files provided yearly from 2009 to 2021 and monthly from 2022 onwards. Each entry represents the capacity factor of a plant or group of plants, calculated as the ratio between the actual generation and the installed capacity.
+
+This dataset is useful for research in renewable energy forecasting, time series analysis, energy systems modeling, and applications of artificial intelligence in the power sector.
+
+## Supported Tasks and Benchmarks
+
+- **Time Series Forecasting**: Predict future capacity factor values for wind and solar energy.
+- **Renewable Energy Modeling**: Analyze the performance of renewable plants over time.
+- **ML for Energy Systems**: Train and evaluate machine learning models for grid optimization and resource planning.
+
+## Languages
+
+The dataset contains metadata and headers in **Portuguese**, as provided by ONS. However, variable names are intuitive and can be easily adapted to English in preprocessing.
+
+## Dataset Structure
+
+### Data Fields
+
+Each file includes the following fields (translated from Portuguese):
+
+- `usina`: Power plant or group name.
+- `data`: Timestamp (YYYY-MM-DD HH:MM).
+- `tipo`: Type of source (`Eólica` for wind, `Solar` for solar).
+- `fator_capacidade`: Capacity factor (float, between 0 and 1).
+
+Note: Some years or months may contain additional fields depending on the ONS publication format.
+
+### File Formats
+
+- CSV (`.csv`)
+- Excel (`.xlsx`)
+- Parquet (`.parquet`) — available for newer monthly files
+
+## Data Splits
+
+There are no predefined train/test/validation splits. Users are encouraged to split the data according to their application (e.g., temporal split for forecasting).
+
+## Licensing Information
+
+This dataset is licensed under the **Creative Commons Attribution License (CC-BY 4.0)**. You are free to share and adapt the data, provided that appropriate credit is given to **ONS**.
+
+More information: [http://opendefinition.org/od/2.1/pt-br](http://opendefinition.org/od/2.1/pt-br)
+
+## Source
+
+- Website: [ONS Historical Operation Data](http://www.ons.org.br/Paginas/resultados-da-operacao/historico-da-operacao/fator-capacidade.aspx)
+- Maintainer: ONS (Operador Nacional do Sistema Elétrico)
+- Contact: relacionamento.agentes@ons.org.br
+
+## Citation
+
+If you use this dataset in your research, please cite ONS as the data provider:
+
+@misc{ons_capacity_factor, title = {ONS Capacity Factor Dataset}, author = {Operador Nacional do Sistema Elétrico (ONS)}, year = {2025}, url = {http://www.ons.org.br} }
+
+
+## Acknowledgements
+
+This dataset is made available through the ONS Open Data Initiative and the AWS Open Data Sponsorship Program: [https://registry.opendata.aws/ons-opendata-portal/](https://registry.opendata.aws/ons-opendata-portal/)
+