Abstract
This paper examines how geographic, climatic, operational, and market conditions influence the profitability and productivity of hybrid renewable power plants that combine reservoir-based hydropower, floating solar photovoltaics, and battery energy storage. Three contrasting regions are examined through case studies in Western Africa (Guinea), Eastern Asia (the Philippines), and Northern Europe (Norway), each with distinct hydrological regimes, solar availability, evaporation intensity, and electricity market structures. A uniform hypothetical watercourse is used across all regions to ensure comparability, and hourly operational scheduling is performed for 39 scenarios spanning dry, median, and wet hydrological years, alternative energy mixes, and system constraints such as grid connection limits. The results show that solar integration boosts net revenue across all regions, with the largest increase (109%) observed in Guinea during a dry year under contractual load obligations. In deregulated electricity markets, such as those in the Philippines and Norway, solar integration does not affect optimal hydropower operation when all production can be sold at market prices. Battery energy storage consistently yields higher profits in the Philippines, with an 8.2% increase in a dry year by exploiting strong price fluctuations. In contrast, in Norway, it has a limited economic impact but can smooth peak generation and alleviate grid constraints. Reductions in reservoir evaporation from floating solar installations depend on maintaining comparable hydropower operating conditions. Without grid connection limits, covering 0.5% of the reservoir surface area reduces annual evaporation by 0.6% in the Philippine median year, while grid constraints alter hydropower operations and increase evaporation by 0.7%.