Abstract

Recirculating water systems are designed to minimize or reduce dependence on water exchange and flushing in fish culture units. Water is typically recirculated when there is a specific need to minimize water replacement, to maintain water quality conditions which differ from the supply water, or to compensate for an insufficient water supply. In this work, recirculating system of fish was used in rearing fish which comprised of fish ponds and treatment pond. Submersible pump was powered by solar energy while the electropome pump was powered by generator provided electricity. Simple annual costs analysis as well as net present value (NPV) method were used to compute the profitability. The total fixed cost of using recirculation system with solar powered pump was higher by N163, 500.00 while the total variable cost of using recirculation system with generator was higher by N244000.00. NPV’s recorded were 299607, -66323, -40409 for generator powered system and 1336085, 575047, 626113 for solar powered system at r = 0.1, 0.2, 0.19, respectively. Results also indicated a shorter payback period for solar system. Solar as power source was more profitable than generator despite its high initial capital.

Key words: Recirculating system, solar photovoltaic, fish culture, net  present value, financial feasibility, fuel generator.