Thermal selective coatings and its enhancement characteristics for efficient power generation through parabolic trough collector (PTC)

World climate is an area of concern due to the use of fossil fuels that have been the most commonly preferred resource of energy since the industrial revolution and urbanization. The target to maintain the lowest level of carbon emissions and greenhouse gases has created an urge to look for renewable energy resources. Among the renewable energy resources available worldwide, solar energy is considered as one of the feasible and mature technologies in view of large-scale commercial deployment. Solar photovoltaic and solar thermal conversion (STC) techniques have been implemented so far and are still advancing towards cost-effective solutions. Parabolic trough collector (PTC) is one such economical and feasible STC technology as far as high-temperature thermal applications are concerned and are being widely used for power generation. This paper is an attempt to present the current scenario of PTC technology along with its various advancements over the years. Further in this paper, selective coatings, coating techniques and heat collection element (HCE) or receiver are discussed in detail with regard to their advancements. The present work also illustrates the progressive trends in PTC technology, particularly with respect to various heat transfer fluids, HCE inserts, selective coatings and other performance factors along with some futuristic aspects with respect to coatings and receiver inserts in view of high thermal performance. Graphic abstract