Analisis Audit Energi Mekanikal dan Elektrikal Berbasis Significant Energy Use (SEU) pada PLTU Stoker

Wisnu Yoga Prasetya (Institut Teknologi PLN, Jakarta)
Dhany Harmeidy Barus (Institut Teknologi PLN, Jakarta)

TIN: TERAPAN INFORMATIKA NUSANTARA
Vol 7 No 3 (2026): August 2026

Energy audits are a crucial strategic instrument for optimizing power plant operational efficiency while supporting national energy conservation programs. This study aims to evaluate the performance of mechanical and electrical systems based on the Significant Energy Use (SEU) approach, as well as to identify applicable energy-saving opportunities in a 7 MW stoker-type coal fired power plant. The research method employed is a detailed energy audit approach through thermal performance calculations using heat rate analysis (input-output and heat loss methods), evaluation of the heat rate gap against the historical baseline, and mapping of Significant Energy Use (SEU) across all main mechanical and electrical equipment. The energy audit results reveal a significant performance degradation, where the actual High Pressure Turbine (HPT) efficiency only reaches 46.52% and the condenser vacuum pressure decreases to 180.32 mmHgA. In addition, auxiliary power consumption is recorded at a relatively high level of 11%. Through operational interventions, the largest energy-saving opportunities can be achieved by restoring the condenser vacuum pressure and improving HPT efficiency. Overall, the total identified energy-saving opportunities amount to 71,765.11 GJ/year, equivalent to 1,714 TOE/year, with an estimated economic value reaching IDR 5,077,394,462.83 annually. Furthermore, reducing auxiliary power from 11.00% to 9.52% provides a potential saving of 50.95 kCal/kWh, alongside savings of 221.80 kCal/kWh from condenser vacuum pressure improvement and 167.49 kCal/kWh from HPT efficiency enhancement. The conclusion of this study confirms that the periodic implementation of technical recommendations derived from the audit is highly effective in reducing the Net Plant Heat Rate (NPHR), lowering the basic cost of electricity provision and ensuring sustainable compliance with environmental regulations.