Techno-Economic Feasibility Study of Solar and Wind Based Irrigation Systems in Northern Colombia

Abstract

Water pumping systems powered by solar and wind energy are a clean, decentralised and economical alternative for the irrigation of crops. The intense droughts experienced over the last few years in Northern Colombiadue to the influential El Niño phenomenonhave reactivated the need for reliable water pumping irrigation systems in the region. This study aims to assess the techno-economic feasibility of solar and wind based pumping irrigation systems, taking as a case study the municipality of Piojó in the Atlántico department. In the first stage of the study the irrigation water requirements were determined by using the software CROPWAT to assess two different crop patterns that represent existing feasible alternatives for small farmers in the region: i) a common crop pattern, which represents the current average distribution of crops for subsistence farming and ii) a fruit cash crop pattern that comprises crops for which well established markets exist in the region. Solar, wind and diesel based pumping systems were sized based on the crop water demands for 1 ha. The unit irrigation costs of the three technologies, the two crop patterns and the three irrigation methods (surface, sprinkler and drip) were calculated and compared. The economic analysis was complemented by a cost-benefit analysis spanning 20 OPEN ACCESS 2 years. Our results show that both the renewable energy based pumping systems (wind and solar) can meet the irrigation water demands of small farmers in the region. The economic analysis shows that windmills are the most cost effective solution, with solar pumping systems in second place. Diesel pumping systems are the least cost effective, even when they do not require capital investment for water storage tanks. The cost benefit analysis demonstrates that none of the irrigation systems are financially feasible for providing water in a common crop pattern. In the case of the fruit cash crop scenario the highest dividends were obtained by the wind pumping system and the lowest dividends by the diesel pumping system. The lowest payback period was obtained by the windmills (7 years) and this payback period could even be shortened to 5 years if the surplus water was used to irrigate larger areas.