Investigation of the power capacity selection problem across small hydroelectric works

The need for utilizing renewable energy sources arises from two main reasons: environmental awareness and the gradual reduction of mineral fuel reserves in relation to human needs. Small hydropower projects do not require a storage reservoir and are considered more environmentally friendly and less intrusive to the environment. There is often confusion regarding large hydropower projects. Small hydropower projects are not simply scaled-down versions of large ones. They have a different construction, design, and operational approach. In this work, basic concepts of energy and small hydropower projects are initially defined based on international literature. Once the concepts are understood, the importance of selecting the appropriate installed power and types of turbines to be installed in each specific small hydropower project becomes apparent. Clearly, the choice of water intake location and the position of the generation station have a significant impact. However, a comprehensive study is conducted specifically for optimizing small hydropower projects based on installed power. Initially, this optimization is carried out with the objective of maximizing the average annual energy generation and achieving a capacity factor of at least 30%. Subsequently, an economic analysis is performed, and an empirical mathematical relationship for cost is developed, which is used in the second optimization that aims to maximize the net annual profit. The entire analysis is based on real data from constructed projects. Finally, a comparison is made between the results of the two optimization processes, leading to the conclusion of whether maximizing energy generation is economically advantageous and what the optimal installed power value is. Energy optimization represents a simpler approach and yields similar results to maximizing net profit; therefore, its use is recommended with a higher capacity factor as a constraint. In conclusion, the significant points of this study are the developed empirical cost relationship, which universally applies to a small hydropower project, the increase in capacity factor in energy optimizations, and the importance of hydraulic losses in the results.