Optimal design of renewable driven polygeneration system: A novel approach integrating TRNSYS-GenOpt linkage

Abstract

Amid energy crisis, population growth, expanding energy demand, the utilities face limited supply of hydrocarbons due to depletion of available reserves. The future of energy supply quest for sustainable polygeneration system by integrating solar thermal, photovoltaic, wind and geothermal energy. The system is designed to produce multiple energy vectors including electricity, space heating & cooling, hydrogen, oxygen, pure water, domestic hot water, and electric vehicle charging. The key innovation lies in optimal integration of energy conversion devices with a multi-tiered backup system featuring thermal, electric, and pressurized hydrogen storage which provide uninterrupted operation during intermittent weathers. The system is modeled and simulated using TRNSYS® and optimized via GenOpt by applying Hooke-Jeeve's algorithm. The results of optimal system having bore hole depth 100 m, collector area 560 m², tank volume 15 m³, wind turbine hub height 46 m, PV module area 1.5 m², electrolyzer electrode area 0.25 m², fuel cell electrode area 0.01 m² show that the solar thermal collector achieves a peak efficiency (η) of 74% and a solar fraction (f) of 0.78, delivering 8020 MJ of heat gain annually. The thermally stratified storage tank provides 7105 MJ of heat energy by efficiently utilizing stored energy. Hydrogen production via electrolyzer reaches 54 m³ per day and 12,696 m³ annually, contributing to green energy storage. The wind energy system generates 1000 kWh at 41% efficiency. This study demonstrates the feasibility and performance of a polygeneration system, highlighting the potential of integrated renewable systems to meet diversified energy needs with enhanced storage solutions.