Designing a solar and wind hybrid system for small-scale irrigation: a case study for Kalangala district in Uganda

Abstract

Background: Dynamics in rainfall patterns are posing a threat to crop production in Uganda. Irrigation can be used to ensure constant production; however, the motorized powered irrigation methods are quite costly to run in addition to being environmentally unsustainable. There is thus need for alternative irrigation methods. Renewable energy sources which are readily available can be used to power irrigation systems. This study hence sought to design an appropriate wind-solar hybrid system for irrigating 1 acre of banana plantation in Kalangala district, Uganda. Methods: Using metrological data, mean wind speed and monthly solar irradiance of global radiation horizontal for the district were analysed. A wind-solar hybrid system was optimally designed for a standalone drip irrigation system of 450 banana plants on 1-acre land with water requirement of 33.73 m 3 d −1 . The wind turbine was simulated to analyse for static pressure, cut plane flow behaviour, turbulence intensity and stress distribution exposed at 20 m s −1 wind speed. A cost analysis was done to estimate the total project investment, maintenance and operational cost, annual project gross income, net income stream and the annual net real rate of returns. Results and conclusions: The simulation results showed that the system could effectively operate at speeds of 20 m s −1 without deformation. The net present value of income stream for the first 5 years at r = 5% was 12,935,468 UGX with a net real rate of return of 3.5% per year. The study will, therefore, be a useful guideline in making investment decisions in hybrids irrigation systems.

Impact analysis of time‐varying voltage‐dependent load models on hybrid DG planning in a radial distribution system using analytical approach

“…The landscape type is considered as small towns, villages, with agricultural land and for this landscape the friction coefficient is 0.4 as discussed in [5]. Thus, the wind velocity at any height can be found by Hellman's equation, as discussed in [27]:…”

“…In general, the active and reactive power of DG unit at a bus j is given by Q DGj = j P DGj (27) Substituting (25) and (27) in (26) we get…”

Designing A Solar and Motor-Based Hybrid Powered Mobile Sprinkler System for Small-Scale Irrigation: A Case Study for Auchi Polytechnic Demonstration Farm

“…Water and energy are two interconnected industries, with a 40% rise in energy consumption expected to lead to a 30% increase in water demand (Couto et al, 2013). These high energy demands hence make irrigation adoption limited economically especially to the majority of smallholder farmers who earn less than a dollar per day (Ssenyimba et al, 2020). Renewable energy irrigation pumps are becoming more popular as a solution to the problem of over-reliance on the conventional grid and motorized irrigation pumps (Ssenyimba et al, 2020).…”

“…These high energy demands hence make irrigation adoption limited economically especially to the majority of smallholder farmers who earn less than a dollar per day (Ssenyimba et al, 2020). Renewable energy irrigation pumps are becoming more popular as a solution to the problem of over-reliance on the conventional grid and motorized irrigation pumps (Ssenyimba et al, 2020). Apart from hydropower, there is a growing trend in Nigeria to look into alternative renewable energy sources to help the country's burgeoning industrial sector (Bodunde et al, 2019).…”

“…However, using a renewable energy resource system as a stand-alone system may result in in operation at certain times of the day and seasons, as well as unnecessary operational and lifecycle costs and component oversizing (Adeodu et al, 2019;Rahman et al, 2014a). These constraints can be solved by combining two or more renewable energy resources, such as a solar system and a generator, into a hybrid system (Rahman et al, 2014a;Ssenyimba et al, 2020). A hybrid system has the advantage of improved reliability and gives better energy service when compared to a standalone supply system (Rahman et al, 2014b;Ssenyimba et al, 2020).…”