Phased performance evaluation of hydrogen-based and electricity-driven energy systems under renewable energy expansion for plus-energy buildings

초록

The pathways to reach net-zero emissions drive the need for decentralized and sustainable energy systems based on clean energy carriers, local renewable resources, and multi-energy complementarity. However, previous studies lack a comprehensive evaluation of high-efficiency systems with control strategies, show limited use of renewable energy, and provide insufficient consideration of capacity design and surplus energy. In light of these shortcomings, this study derives zero- and plus-energy building scenarios based on a phased performance evaluation of hydrogen-based and electricity-driven energy systems, considering variations in renewable energy system capacity from energy, environmental, economic, and self-sufficiency perspectives. A control strategy aimed at maximizing energy efficiency and overall performance of the hydrogen-based plus-energy building system is implemented. Additionally, the capacities of major components, including multiple energy storage devices, are designed based on parametric system evaluations and dynamic monitoring analysis. When the renewable energy system is confined to the building footprint, the primary energy saving ratios of the hydrogenbased and electricity-driven plus-energy building systems are 31.5% and 40.4%, respectively. With subsidy support, the payback period of the hydrogen-based plus-energy building system is 8.09 years, whereas the average payback period of the electricity-driven plus-energy building system is 7.13 years. In the zero- and plusenergy building scenarios of the hydrogen-based plus-energy building system, gray hydrogen is fully replaced by green hydrogen, and photovoltaic module installation areas of at least 5.52 times the rooftop area are needed. The net-zero and net-plus energy building scenarios of the electricity-driven plus-energy building system are established based on the primary energy balance through grid interaction, requiring installation areas of at least 2.09 times the rooftop area. Various scenarios capable of improving system performance are developed based on capacity variations of components that accommodate renewable energy and mitigate its intermittency. The surplus renewable energy of each system is shared with hydrogen and electric vehicles, thereby enhancing the energy performance and self-sufficiency of the vehicles.

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