Improving nuclear flexibility by high-temperature production and burning of hydrogen energy: Feasibility and economic evaluation

Flexibility is becoming highly important for the power grid as the renewable energy contribute towards a higher proportion. As basic power source, nuclear power plants (NPPs) are also expected to improve flexibility capability to facilitate the high penetration of the renewable energy. The present work provides a novel path combined solid oxide electrolysis cells (SOECs) and H 2 –O 2 burning to improve the flexibility capacity for nuclear power and realize the coupling supply of H 2 , O 2 and hot water . The flexibility performance of NPPs-SOECs system is estimated based on a self-established thermal model. Within the SOECs temperature ranges of 600 °C–1000 °C, a lowest unit load of 20.4 % with a minimum unit electrical consumption of 3.08 kWh/Nm 3 for hydrogen production can be achieved during charge period. In discharge period , a highest unit load of 113.3 % can be achieved based on H 2 –O 2 burning. The cycle efficiency of NPPs-SOECs can reach 56.5 % in this simulation. When NPPs are coupled for H 2 production, SOECs have the highest energy utilization efficiency of 40.5 %, significantly higher than that of alkaline electrolysis and proton exchange membrane . • A novel NPPs-SOECs system for integrated flexibility and H 2 production is proposed. • A lowest unit load of 20.4 % can be achieved for NPPs. • A highest cycle efficiency of 56.5 % can be achieved for NPPs-SOECs system. • SOECs have higher energy utilization efficiency than AE and PEM when coupled with NPPs for H 2 production.