Optimization of an energy management system for PEMFCs including degradation

• A general degradation model is proposed and validated. • A new optimization method for long-term analysis is proposed. • Degradation effects can increase OPEX up to 12% in rule-based EMS. • Optimized EMS solution can minimize impacts in OPEX to 4%. • Oversizing PEMFCs and batteries can significantly reduce costs by 8%. Proton exchange membrane fuel cells (PEMFCs) can efficiently convert hydrogen into electricity for stationary applications, providing an emission-free solution for backup power and off-grid applications. However, degradation and partial load operation introduce new challenges that have been seldom addressed in the design and optimization of energy management systems (EMS). Thus, this study proposes multiple novelties in modelling and optimization to include these effects and overcome associated computational challenges by proposing a new rolling horizon optimization method. The results indicate that optimized EMS can reduce the equivalent annual operating costs (EAOC) by up to 15% compared with a rule-based method with fixed fuel cell load. Additionally, degradation effects can lead to a 12% increase in OPEX due to efficiency losses, which can be reduced to 4% with the proposed optimization method. Additionally, slightly oversizing the number of PEMFC units or providing enough battery support can lead to EAOC reductions up to 6%. Furthermore, hydrogen cost variation (1–2 USD/kg) has the largest effect on the EAOC (up to 20%) among the key economic parameters considered.