In recent years, linear Fresnel (LF) collector systems have been developed as a technical alternative to parabolic trough (PT) collector systems. While in the past, LF systems focused on low- and medium-temperature applications, today, LF systems are equipped with vacuum receivers and, therefore, can be operated with similar operating parameters as PT systems. Papers about the technical and economical comparison of specific PT and LF systems have already been published (Dersch et al., 2009, "Comparison of Linear Fresnel and Parabolic Trough Collecor Systems—System Analysis to Determine Break-Even Costs of Linear Fresnel Collectors," Proceedings of the 15th International SolarPACES Symposium, Berlin; Giostri et al. 2011, "Comparison of Two Linear Collectors in Solar Thermal Plants: Parabolic Trough vs. Fresnel," ASME 2011 5th International Conference on Energy Sustainability, Washington, DC; and Morin et al., 2012, "Comparison of Linear Fresnel and Parabolic Trough Collector Power Plants," Sol. Energy, 86(1), pp. 1–12). However, the present paper focuses on the systematic differences in optical and thermodynamic performance and the impact on the economic figures. In a first step the optical performance of typical PT and LF solar fields (SFs) has been examined, showing the differences during the course of the day and annually. Furthermore, the thermodynamic performance, depending on the operating temperature, has been compared. In a second step, the annual electricity yield of typical PT and LF plants has been examined. Solar Salt has been chosen as the heat transfer fluid. Both systems utilize the same power block (PB) and storage type. Solar field size, storage capacity, and PB electrical power are variable, while all examined configurations achieve the same annual electricity yield. As expected for molten salt systems, both systems are the most cost-effective with large storage capacities. The lower thermodynamic performance of the LF system requires a larger SF and lower specific SF costs in order to be competitive. Assuming specific PT field costs of 300 €/m² aperture, the break-even costs of the LF system with Solar Salt range between 202 and 235 €/m², depending on the site and storage capacity. In order to confirm the major statements, within a sensitivity analysis, it is shown that a variation of SF and storage costs does not have a significant impact on the relative break-even costs of the LF system.

This study compares the levelized cost of energy (LCOE) of parabolic trough solar power plants using thermal oil or two different molten salt mixtures located at three different sites and with different thermal storage capacities. The necessity of using appropriate model approaches for the temperatures along a loop of the solar field is discussed, as well as the utilization of heat from thermal storage for freeze protection of the molten salt plants. The ternary salt mixture with a lower temperature limit of 170 °C and an upper temperature limit of 500 °C shows the lowest LCOE for all sites and almost all investigated storage capacities. Molten salts as heat transfer fluids are particularly favorable for sites with high irradiation and plants with large storage capacities of more than six full load hours.

The objective of this study is to present updated estimates of the cost of concentrated solar power (CSP) projects that are relevant for the current Italian market. To this end, a comparative techno-economic analysis of different CSP plant types based on parabolic trough (PT) collectors was conducted, considering various scenarios with respect to heat transfer fluids, location and storage size. The scenarios were defined in accordance with a number of requirements, including the utilization of technologies produced in Europe (in alignment with the EU's Net-Zero Industry Act), the availability of performance and cost data from existing literature, and/or the authors' own experience, as well as the eligibility for incentives according to the initial drafts of the new support measure. The analysis employed two distinct modelling tools, developed by ENEA and DLR, respectively. These offered varying levels of detail in the description of the plant behavior. Thus, cross-checking of the results was enabled. Additionally, insights were gained concerning the impact of the chosen modelling approach on performance assessment.