To address the challenges of cross-timescale electrothermal dynamics characteristics and the flexibility and stability issues caused by high renewable energy penetration in SOFC-based distributed energy systems, a distributed energy system using solid oxide fuel cells (SOFCs) is proposed. Based on the analysis of SOFC electrothermal dynamics characteristics across different timescales, an innovative SOFC-assisted peak shaving control strategy is designed.  Using the Simulink simulation platform, the electrothermal dynamic response and coordinated operation under varying load fluctuations are explored. Results indicate that thermal maintenance effectively reduces SOFC thermal inertia, enhancing peak shaving capability and stability. The control strategy ensures safe operation while meeting electrothermal demands, providing a theoretical basis for regulating and stabilizing SOFC-based distributed energy systems.