Solar Thermal Energy Storage in Power Generation Using Phase Change Material with Heat Pipes and Fins to Enhance Heat Transfer

Abstract

Phase change materials absorb or otherwise release heat at close to a constant temperature during its melting and solidification phases. This is a very sought after property in power generation, where a high temperature heat source is required within a narrow temperature range as heat input for the turbine. Solar tower technology provides a high temperature heat source, but unfortunately it is time dependent. A sufficient amount of this heat may be stored in a phase change storage system which can deliver dispatchable heat. In such a storage system the phase change material needs to be exposed to a sufficient heat transfer area to melt or solidify at sufficient rates. In this study this is achieved with heat pipes with metallic fins. The analysis of this design included testing an experimental module during heat absorption and heat removal cycles, as well as a numerical analysis to model the storage module. To determine the parameters for a specific phase change storage system in a high temperature solar tower application the validated numerical thermal response simulation is incorporated. Certain solar input conditions and load cases are applied to the phase change storage system model and the size and geometry of the solar thermal storage system are determined from this analysis.

Numerical Analysis of Shell-and-Tube Type Latent Thermal Energy Storage Performance with Different Arrangements of Circular Fins

“…Furthermore, the combination of solar power and LTS, like solar heating systems and solar cooking, is currently being researched [1]. Malan et al [3] examined the potential use of LTS in solar thermal power plants for performance optimisation. Due to the variety of possible applications, several reviews have been carried out inter alia by Sharma et al [1]; Zalba et al [4]; and Farid et al [5].…”

Thermal Conductivity Enhancement of Phase Change Materials for Low-Temperature Thermal Energy Storage Applications

“…In residential applications, an appropriate thermal storage system can efficiently improve indoor thermal comfort degree by transporting much of excessive energy from daytime to nighttime and from hot days to cold days [27,31,[42][43][44]. PCM-based storage systems could efficiently be integrated with concentrated solar power plants, solar water heating systems, solar greenhouses, solar cooking systems, and photovoltaic systems [45][46][47]. Nevertheless, as discussed before, many commonly-used PCMs have poor thermal conductivity [45][46][47][48][49].…”

“…PCM-based storage systems could efficiently be integrated with concentrated solar power plants, solar water heating systems, solar greenhouses, solar cooking systems, and photovoltaic systems [45][46][47]. Nevertheless, as discussed before, many commonly-used PCMs have poor thermal conductivity [45][46][47][48][49]. Therefore, PCMs with enhanced thermal conductivity are required to overcome the discrepancy between the supply and demand (i.e., considering the impermanency of thermal energy supply through renewables) [39].…”

The influence of thermal contact resistance on the relative performance of heat pipe-fin array systems

“…External arrays of fins, foils, and porous metallic foams have been added to HPs to reduce the overall system thermal resistances [16][17][18][19][20][21][22][23][24][25][26][27][28][29].…”