This special issue will publish original research papers and review articles related to high-performance building envelope, efficient energy system, and photovoltaic, energy storage, direct current, and flexibility technology (PEDF).

This special issue focuses on sustainable building technology, aiming to tap the potential of energy saving and carbon reduction in urban buildings, and help the realization of the grand vision of China's urban and rural construction field - "2030 carbon peak, 2060 carbon neutral," mainly including the following three aspects:

• High-performance building envelope technology, including high-performance insulation technology, high-performance doors and windows, efficient shading systems, etc.
• Efficient energy systems, including efficient cooling and heating equipment and system, efficient lighting system, etc.
• Renewable energy utilization technology, especially PEDF (Photovoltaic, Energy storage, Direct current, Flexibility) technology, including BIPV/BAPV, flexible energy use, energy storage system, and so on.

Keywords: high-performance building envelope, efficient energy system, photovoltaic, energy storage, direct current, and flexibility technology (PEDF)