AN INTEGRATED MODELING APPROACH FOR HYDROPOWER POTENTIAL ASSESSMENT AND SUITABILITY ANALYSIS

Abstract

As the demand for energy continues to rise, experts and energy supply agencies are actively seeking diverse power sources to fulfill the demands. Among several non-renewable and renewable energy resources, hydropower become a priority because of its sustainability and environmental suitability. As a result, experts in the field focus on developing approaches for suitability assessments for hydropower projects and analyzing the spatial distribution of the potential sites at regional as well as global scales. This strategic approach would enable policymakers and government stakeholders to gain valuable insights, facilitating the idea and planning of future sustainable and environmentally compatible energy development endeavors. This study focused on hydropower potential assessment and feasibility analysis, including the catchment and global scale, as several limitations exist in the existing literature. For example, previous studies have limitations in considering the recently updated hydrological information. In addition to this, some of the global scale studies used topographical information that has left some parts of the landmass uncovered. Moreover, many of these studies relied on relatively coarse-resolution digital elevation models (DEM), which may not accurately capture where finer details are required for precise assessment. Similarly, regarding regional and catchment-based hydropower potential assessment studies, many of the proposed methodologies primarily focus on assessing small-scale and Run–of–River (RoR) type hydropower potential possibilities. However, it is reported that a significant amount of untapped hydropower potential is available, especially in developing countries, which needs to be assessed via the development of comprehensive methodological frameworks. Therefore, the study comprises two main parts. The first part of the study provides an assessment of the worldwide hydropower potential, mainly the RoR type, and evaluates the spatial distribution. The analysis focused on assessing possible hydropower potential and evaluations under theoretical, technical, economic and environmental constraints. The study used a relatively recent (1965 – 2014) global runoff dataset having a resolution of 0.5o x 0.5o for the computation of design discharge and a 3' x 3' (approximately 90 m x 90 m at the equator) resolution DEM covering 90oN - 60oS, for topographical analysis. Design discharges (Qd) at 30%, 75% and 95% flow dependability were used in the assessment and evaluations. The study assessed the suitability of potential sites with an interval of 0.5 km to 5 km in the river networks and used empirical relations derived from the observed cost of electromechanical equipment to corresponding head (H) and installed power (P) for economic analysis. The analysis revealed that the global theoretical hydropower potential ranges from 25.48 Peta watt-hours per year (PWh/yr) at 95% flow dependability to 184.17 PWh/yr at 30% flow dependability. Of these, the energy ranges from 7.06 PWh/yr to 49.05 PWh/yr, which is technically feasible considering a design discharge determined from a flow in ranges of 95% to 30% flow dependability. After excluding environmentally unsuitable and economically less competitive (Levelized Cost of Electricity (LCoE) > US$ 0.1/kWh) potential sites, it was estimated that an exploitable hydropower potential of 5.42 PWh/yr at 95% flow dependability to 39.56 PWh/yr at 30% flow dependability would be available globally.