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Harvesting cold energy from the universe by radiative cooling (RC) is a promising zero‐carbon route for green cooling. However, low power density and spatiotemporal energy mismatch of RC are great challenges for realizing efficient space cooling. Herein, a facile strategy for regulating cold energy from the universe by bifunctional phase change materials (PCM) for sustainable cooling is proposed. A bifunctional phase‐change composite film (PCCF) by integrating RC coating with PCM for 24‐h cold energy harvesting, storage, and utilization is demonstrated. The bifunctional PCCF can harvest cold energy from the universe and regulate the redundant cold energy generated by nighttime RC to compensate for the cold shortage of daytime RC, realizing flexible regulation of all‐day RC and setting new records of cooling power up to 180 W m−2 with sub‐ambient temperature drop of 11.95 °C. The work offers a promising strategy for zero‐carbon sustainable cooling by maximizing RC with cold energy storage. [ABSTRACT FROM AUTHOR] more...

The trigeneration combined the electricity, cooling and heating makes adiabatic compressed air energy storage system (ACAES) popular as an energy storage technology. Based on thermodynamic analysis, this paper studies the influence on the system performance of four variable factors, including compression stages, expansion stages, water (heat storage medium) mass flow rates in charging process and discharging process to provide a guidance for the design of ACAES for different user demand. The results show that changing these four factors can achieve different energy output distributions in a very wide range (power supply ratio is 0.50–0.86, heating output ratio is 0.00–0.39, cooling supply ratio is 0.00–0.41). Simulation results also indicate that fewer compression and expansion stages are suggested for the cases requiring shorter running time. Furthermore, according to this study, less compression stages than expansion is good for electricity generation and more compression stages is good for cooling supply. And for large heating supply demand, less compression is suggest. Besides, the energy efficiencies for different configurations of trigenerative ACAES are also achieved which are changed from 0.62 to 0.87 and the best configurations with highest system efficiency are also presented. Finally, by economic analysis, the most economic condition is achieved. • Single ACAES is used for trigenerative application to meet different energy demands. • Thermodynamic, exergy and economic analysis are used to perform the trigenerative application. • The energy efficiency of trigenerative ACAES is changed from 0.62 to 0.87. • The payback period of trigenerative ACAES is 3.4–6.8 years with different configurations. • The design guidance of compression stage, expansion stage, thermal storage are provided. [ABSTRACT FROM AUTHOR] more...