Cogeneration from Natural Gas as a Strategy for the Energy Transition in an Industry with High Electricity Demand

Abstract

The energy transition requires industrial energy technologies that can reduce emissions while maintaining reliable supplies of electricity and thermal energy. Natural gas-based cogeneration can improve fuel use by producing electricity and useful thermal energy simultaneously. This study evaluated the technical, economic and environmental performance of a cogeneration plant installed at a high-energy-demand manufacturing facility in Zapopan, Jalisco, Mexico. The plant comprised four Caterpillar G3520H engine-generator sets with a total installed electrical capacity of 10 MW and two lithium bromide absorption chillers, each rated at 476 tons of refrigeration. One year of SCADA operating data was analysed, including electrical generation, cooling production, natural gas consumption and equipment operating conditions. Monthly average electrical generation ranged from 4,510 to 6,717 kW, with an annual average of 6,023 kW. Cooling production ranged from 160 to 372 TR and averaged 299.6 TR, while natural gas consumption averaged 1,602.5 Nm³ h⁻¹. The regression between fuel consumption and power generation was strong (R² = 0.984), indicating stable plant behaviour. The calculated overall cogeneration efficiency was 76.9% when electrical output and recovered thermal energy were considered. The assessment estimated an annual carbon dioxide reduction of 11,607 tons relative to conventional generation assumptions, while the economic analysis indicated a payback period of approximately 4.36 years. These findings suggest that natural gas-based cogeneration may offer a practical transitional option for improving industrial energy efficiency, reducing operating costs and supporting reliable electricity and cooling supply while renewable and lower-carbon systems continue to develop.