Theoretical and experimental studies were performed for a solar-ground source heat-pump (SGSHP) system with a vertical double-spiral coil (VDSC) ground heat-exchanger (GHX). The heating mode of the SGSHP system is alternated between a solar energy-source heat-pump (SSHP) and a ground-source...

Experimental results of the gas-hydrate R141b cool-storage process are used to study the performance of a new type gas-hydrate cool-storage system. The relations among the cooling rate of the cool-storage medium, the degree of subcooling of crystallization, the formation rate of gas-hydrate, the...

Thermodynamic optimization models of gas-hydrate cool storage and cool release processes are established in this paper. The optimal temperature configuration at the sensible heat transfer stage and the optimal gas hydrate phase change rate configuration at the phase change stage in the processes...

Supercritical CO2 has good mobility and certain heat capacity, which can be used as an alternative of water for heat recovery from geothermal reservoirs, meanwhile trapping most of injected CO2 underground to achieve the environmental benefits. In this paper, different types of geothermal...

China has experienced off-seasonal power shortages in recent years, where the growth in capacity supply exceeds the power demand. This paper investigates the mechanism of power shortages in China by estimating the capacity expansion and capacity utilisation models with the annual data of 30...