An alternative on-site accommodation pathway and techno-economic evaluation for Desert-Gobi-Wasteland energy bases by the wind-solar-thermal-chemical multi-energy integration

Developing Desert-Gobi-Wasteland (DGW) energy bases is critical for scaling up renewable energy deployment and advancing the global energy structure transition. However, the inherent intermittency and volatility of wind and solar power hinder their large-scale integration. Chemical energy carriers (e.g., hydrogen, ammonia, methanol) have emerged as promising solutions for electrical energy storage to address this challenge. This study proposes a novel wind-solar-thermal-storage-hydrogen-ammonia-methanol (WSTS-HAM) integrated energy system for DGW energy bases, aiming to mitigate fluctuations in renewable power output. On this basis, an integrated planning and scheduling model is established to minimize the base's annualized cost and determine the optimal system capacity configuration. An 8760-h annual chronological production simulation is conducted, and system performance is evaluated using two key economic metrics: levelized cost of ammonia (LCOA) and levelized cost of methanol (LCOM). Jiuquan City in Gansu is selected as a case study, where the WSTS-HAM system is analyzed based on local wind and solar resource endowments. Results demonstrate that wind-solar complementarity significantly improves system economic efficiency and identifies an optimal wind-solar ratio that minimizes energy storage capacity requirements, with the minimum LCOA and LCOM reaching 7006.75 CNY/ton and 8949.58 CNY/ton, respectively. Besides, analysis of thermal power phase-out impacts reveals that the system's reliance on battery storage increases, while total system cost and carbon emissions both decrease continuously. Sensitivity analysis indicates that coal price fluctuations exert a greater impact on LCOA than on LCOM, with maximum increases of 2.72% and 2.22%, respectively.