Optimal energy management and techno-economic assessment of hydrogen energy production system incorporated with photovoltaic and battery storage

Green hydrogen (H₂) has garnered significant attention in recent years as a key component of a zero-emission future due to its diverse range of applications. The energy management (EM) strategy of the green H₂ production system (HPS) plays a crucial role in facilitating efficient and cost-effective green H₂ production by regulating the operating point of the electrolyzer (EL) to achieve economic and operational benefits. This paper proposed an optimal EM scheme for photovoltaic-based battery (BT) grid-connected green HPS. The HPS is intended to meet H₂ and electricity demands of an industrial HPS. The objective of the EM scheme is to minimize the cost of green H₂ production by minimizing the total system costs of the HPS, while ensuring the system operates reliably. The objective is realized by incorporating the EM strategy model with Z-score statistical values of past grid electricity costs which reflect seasonal electricity price trends. This enables the green H₂ production and storage when electricity prices are relatively low. The EM variables considered for the optimization include: EL status (EL on/off operation of the EL), electricity purchased from the grid, input power to the EL and output power from EL (H₂ production rate), energy stored in the H₂ storage tank and BT, discharging and charging power of the BT and H₂ tank. Four test case systems (Case 1-4) are used to demonstrate the techno-economic feasibility of the proposed EM scheme model for the green HPS. The performance EM scheme has also been demonstrated for both seasonal and intraseasonal storage. Lastly, sensitivity analysis has been performed to investigate the impact of PV power, and EL capacity on the cost of H₂ and EL efficiency.