The articles in this issue were authored and co-authored by researchers from Universitas Borneo Tarakan (Indonesia), PT. PLN (Persero) Tarakan (Indonesia), Universitas Pertamina (Indonesia), Chulalongkorn University (Thailand), Universitas Syiah Kuala (Indonesia), and Universitas Sumatera Utara (Indonesia).

This issue of JESCEE presents significant contributions across power systems forecasting, waste-to-value process engineering, sustainable supply chain management, clean hydrogen production, and industrial/aerospace automation, focusing on operational efficiency, environmental impact, and emerging clean energy technologies.

Key articles include:

• Electrical Load Forecasting A comparative study using ARIMA, SARIMA, and Linear Regression models to forecast short-term electricity demand at PT. PLN (Persero) Tarakan, with SARIMA(1,1,0)(1,0,0) achieving the best accuracy (MAPE 6.13%).
• Liquid Fertilizer from Slaughterhouse Waste An investigation into fermenting chicken slaughterhouse wastewater with sucrose and EM4 bacterial solution to produce liquid organic fertilizer, tested on kangkong plant growth.
• Reverse Logistics & Consumer Satisfaction An empirical study on how packaging-return reverse logistics practices at a natural cosmetics company influence consumer satisfaction, using simple linear regression analysis.
• Hydrogen Production via Gasification A process simulation and life cycle assessment of hydrogen gas production from heavy fuel oil gasification using UniSim Design and GaBi software, achieving 98.02% hydrogen purity alongside economic feasibility analysis.
• Digester Automation for CPO Production The design and simulation of an Arduino Uno-based automation system with multisensing technology to control temperature, material level, and agitation in crude palm oil digester machines.
• Active Noise Control on UAV Engines An experimental study applying Active Noise Control techniques to reduce noise from a DLE Gas Engine 30 drive motor on an unmanned aerial vehicle, achieving up to 1.36 dB reduction.

This volume delivers valuable insights into optimizing energy demand planning, converting industrial waste into economic value, strengthening green supply chain practices, advancing cleaner hydrogen technologies, and enhancing automation and noise control in industrial and aerospace applications.