Two-phase heat transfer technologies can offer efficient, low-cost, and long-life heat exchange or thermal management and thus are playing a significant role in energy collection, transportation, and utilization. The passive two-phase heat transfer devices are some of the key elements of sustainable development in relevant fields, and their application to improve the practicality and efficiency of renewable energy use greatly benefits the worldwide reduction in fossil energy and CO2 emissions. In recent years, adopting advanced passive two-phase heat transfer technologies for the enhancement and revolution of renewable energy utilization processes is getting increasing attention. A considerable amount of studies on passive two-phase heat transfer devices involving two-phase flow mechanism, fluid mechanics analysis, heat transfer enhancement, material upgrades, and structure optimization has been devoted.

To further promote and spread passive two-phase heat transfer technologies for renewable energy utilization, this newly launched Special Issue is open to cutting-edge research addressing current problems and future challenges. Original research papers reporting critical review, and theoretical and experimental investigation of innovative two-phase heat transfer technologies for sustainable energy utilization are welcomed. The potential backgrounds of renewable energy uses for the passive two-phase heat transfer technologies include but are not limited to: solar energy, geothermal energy, air source, water source, nuclear energy, waste heat.