Thermal Spray Processes in Concentrating Solar Power Technology

Felice Rubino,Pedro Poza,Pierpaolo Carlone,Germana Pasquino

doi:10.3390/met11091377

Abstract

Solar power is a sustainable and affordable source of energy, and has gained interest from academies, companies, and government institutions as a potential and efficient alternative for next-generation energy production. To promote the penetration of solar power in the energy market, solar-generated electricity needs to be cost-competitive with fossil fuels and other renewables. Development of new materials for solar absorbers able to collect a higher fraction of solar radiation and work at higher temperatures, together with improved design of thermal energy storage systems and components, have been addressed as strategies for increasing the efficiency of solar power plants, offering dispatchable energy and adapting the electricity production to the curve demand. Manufacturing of concentrating solar power components greatly affects their performance and durability and, thus, the global efficiency of solar power plants. The development of viable, sustainable, and efficient manufacturing procedures and processes became key aspects within the breakthrough strategies of solar power technologies. This paper provides an outlook on the application of thermal spray processes to produce selective solar absorbing coatings in solar tower receivers and high-temperature protective barriers as strategies to mitigate the corrosion of concentrating solar power and thermal energy storage components when exposed to aggressive media during service life.

Highlights

After photovoltaic (PV), concentrated solar power (CSP) is the second class of solar technology adopted worldwide to exploit solar energy to produce electricity
This paper provides an outlook on the application of thermal spray processes to produce selective solar absorbing coatings in solar tower receivers and high-temperature protective barriers as strategies to mitigate the corrosion of concentrating solar power and thermal energy storage components when exposed to aggressive media during service life
One of the main goals for engineers and designers is to increase the amount of energy collected from solar radiation, maximizing the heat delivered to the transfer fluid and, at simultaneously, reducing the heat loss at the receiver

Summary

Introduction

After photovoltaic (PV), concentrated solar power (CSP) is the second class of solar technology adopted worldwide to exploit solar energy to produce electricity. Maximizing the absorption of solar energy and reducing the heat losses from the receiver to the environment (i.e., the thermal emittance) are the key factors to increase the solar-to-heat efficiency, which constitutes almost 40% of the energy balance in a CSP plant (Figure 2) [12] It means that receivers should have optimized optical properties and microstructure stability in the operative temperature range. The structural materials, e.g., steels and aluminum alloys, usually employed in the construction of the elements that compose the CSP plants (namely heliostats, collectors, and receivers) do not provide the required optical properties necessary for efficient exploitation of solar energy For this reason, coatings are used to cover the surface of these elements to achieve the optimal values of solar absorptance, reflectance, and thermal emittance, and simultaneously improving (when possible) the structural integrity of CSP components. The readers may read the works of Kennedy [18], Atkinson [19], and Xu [20] for more exhaustive information about the materials used and their chemical composition, the typical configurations of the coatings, the field of application, and the main failure mechanisms

Thermal Spray Processes for Selective Absorber

Corrosion Resistant Coatings in TES System

Findings

Conclusions and Future Perspectives