Thermal loss in concentrated solar power plants: A review of external and cavity receivers

A vast solar resource remains underutilized, and cross-country comparisons show a persistent gap between high direct normal irradiation and realized solar generation. Concentrating solar power plants with external and cavity receivers can provide dispatchable, high temperature heat, but receiver performance is constrained by thermal losses. This review synthesizes loss mechanisms and evaluates models, experiments, and mitigation strategies across receiver types and operating regimes. Conduction through supports is typically negligible, contributing less than 1%, while convection ranges from a few to several tens of percent and increases with wind exposure and receiver orientation; radiation dominates above 500^∘C because of its fourth-power dependence on temperature. External receivers incur higher losses than cavity receivers due to full ambient exposure and a larger sky view factor, whereas recessed cavity apertures reduce convective exchange and reradiation. We classify key design and operational levers, including aperture shaping and shielding, panelization, shaped geometries, internal fins and microchannels, air curtains, mass flow scheduling, and advanced materials such as low-emissivity coatings, aerogels, and phase change materials. Reported outcomes include up to 50% total loss reduction at 800^∘C through coordinated geometry and surface optimization, multi-megawatt savings from partial dome shielding under moderate winds, and about 30% convective loss reduction from wind blocking and tuned air curtains. The review consolidates scattered evidence into a hierarchy that aligns interventions with the dominant loss pathway to improve receiver thermal efficiency.

Solar energy

Solar Energy

313

0038-092X

N/A

N/A

24