# Techno-Economic Assessment of an Innovative Small-Scale Solar-Biomass Hybrid Power Plant
## 1 Introduction  
The need to limit the impact of the power generation sector on the environment is clearly identified in the UN's Sustainable Development Goals, which propose actions in the areas of energy, the atmosphere, and climate change [1]. Currently, there is evidence of a nearly linear relationship between cumulative greenhouse gas (GHG) emissions and global temperature variation [2]. In such a scenario, there has been a growing interest in the development and application of cleaner and more sustainable power generation technologies [3]. Renewable energies constitute a technically feasible alternative, allowing for the simultaneous reduction of GHG emissions.  
Unlike other renewable technologies such as wind or photovoltaic, concentrating solar power (CSP) plants are currently not economically competitive compared to fossil fuel-based power generation due to their high production costs [4; 5]. Additionally, CSP technology has an added disadvantage in managing electricity production due to the high variability of solar resources, which necessitates costly thermal energy storage systems [6]. However, there is a wide consensus in the scientific community that one of the most promising alternatives for reducing the costs of CSP plants is hybridization with other lower-cost generation technologies [7], such as direct biomass combustion, which is considered carbon-neutral [8; 9]. The cost reduction attributed to CSP-biomass hybridization stems from the shared use of infrastructure and common equipment [10]. In addition to the aforementioned production cost reduction, hybridization contributes to improving the dispatchability of electricity generation compared to conventional CSP plants, which are more or less subject to the randomness of solar resources [11; 12]. Furthermore, otheradditional advantages derived from CSP-biomass hybridization include improved thermal cycle efficiency and reduced environmental impact due to the smaller solar field size and lower water consumption [13].  
While most publications regarding CSP-biomass hybridization refer to theoretical studies [14; 15; 16], the most notable milestone in this field is the Termosolar Borges project in Spain. This 22.5 MW capacity plant, operational since 2012, was the first commercial plant to use biomass from agricultural residues to complement solar resource generation through parallel hybridization [17]. The Brenderslev plant in Denmark, although smaller in size (4 MW), is also noteworthy [18].  
Economic analysis is a fundamental part of any feasibility study, especially when addressing projects of an innovative nature [19]. In the field of power generation plants, the Levelized Cost of Energy (LCOE) serves as the benchmark indicator for comparing different technologies [20; 21] and as a guide for design optimization [22; 23]. However, the LCOE has limitations, such as not taking into account the dispatchability of electricity production when evaluating certain renewable technologies [24; 25]. In the specific case of CSP-biomass hybridization, noteworthy economic analyses were conducted by [PERSON] et al. [26] and [PERSON] et al. [27].  
The objective of this study was to assess the economic viability of a CSP-biomass hybrid plant based on an innovative series/parallel-process scheme. The hypothetical power plant analyzed in this work had a capacity corresponding to a small scale, with a chosen gross generation capacity of 2 MW. This study was structured into three parts. First, the materials and methods applied in this work, including the influence of the selected location, technical plant characterization, and economic analysis details, are presented. Next, the obtained results are analyzed, encompassing daily simulations, annual balances, and the calculation of the LCOE. Finally, the conclusions drawn from this analysis are presented.