## 1 Introduction  
Corrosion represents a major concern in numerous industries (maritime, geothermal, petrochemical, etc.) due to the potential damage that can be caused by it [1; 2; 3]. The need for the constant replacing or repairing of various pieces of equipment or parts, leads to high maintenance costs. Research is focused on developing new materials, with improved properties, which can serve as options as commercially available alternatives.  
One of the main concerns for the geothermal industry is represented by the erosion-corrosion effect that affects the in-work turbine blades, which are in direct contact with the geothermal steam. Due to their specific effects and superior properties, the use of high-entropy alloys is desired in multiple applications, where corrosion represents the main issue. The literature [4; 5; 6; 7] presents these alloys as a viable solution for different applications or domains and they represent the subject of this paper.  
According to our recent research on corrosive-resistant materials for the geothermal environment [8; 9; 10], promising results were obtained for high-entropy alloys from the CoCrFeNiMo system, produced from a liquid [11] and solid state [12]. The alloys were tested in corrosive media and the results published [12; 13].  
For this application, the CoCrFeNiMo\({}_{0.85}\) high-entropy alloy was analyzed in terms of economic efficiency, as a possible solution to improve the in-work geothermal power plant equipment. The initial powder's composition was decided based on the theoretical calculation of the valence electron concentration (VEC). The results indicated that, for a value of 7.87, a mixture of both FCC and BCC phases were present and were later on confirmed [10]. According to [PERSON]. [PERSON] et al. [14], the mixture of phases indicates there are properties such as high ductility and strength in the final alloy.  
The coatings were subjected to corrosion testing and the results showed that after performing the testing in a saline solution (3.5 wt% NaCl), a corrosion rate of 0.00016 mm/year resulted. Good adhesion was observed from the pull-off test results where no cohesive or adhesive types of failure occurred. [8].  
In an article published by [PERSON] et al. [15; 16], the steam effect on the geothermal turbines was discussed, and it was mentioned that for a period of 15-20 years, the maintenance costs could reach USD 20 mil [17]. This case was studied for a geothermal power plant located in Hellisheioi, Iceland.  
From an economical point of view, the main costs are represented by the turbine transportation from the power plant to the producer or service facility and by replacing the turbine blades when the damage cannot be undone by refurbishing.  
The electrospray deposition method could represent a viable solution for the highly corrosive media due to the efficiency of the thin high-entropy layers. Advantages such as local repairs are also taken into consideration, where parts affected by the erosion effect could be adjusted.  
By taking into consideration the presented factors, for this paper, economic calculations were performed in order to establish the cost efficiency of CoCrFeNiMo\({}_{\text{x}}\) high-entropy alloy coatings by electrospray deposition.