Environmental and Economic Cost Analysis of a Solar PV, Diesel and hybrid PV-Diesel water Pumping Systems for Agricultural Irrigation in Rwanda: Case study of Bugesera district

Abstract

Rwanda agriculture sector has a significant impact on country’s economy whereby 80% of population depend on agriculture. Poor performance of agriculture sector affects economic development in different angles as 91% of food consumption and 34% GDP are from national agriculture. One of the critical problems currently being faced by Rwandan government is to ensuring sustainable food production. Many irrigation projects were started with the principal objective of enhancing agricultural production while avoiding dependence on rain-fed agriculture, but the problem of power to pump water is still a major barrier. Therefore, that’s why several economic analyses have been conducted in this thesis to establish the most cost effective solution for irrigation and to evaluate the project profitability toward the country’s vision 2020. This study intends to analyze environmentally and economically the cost of a solar PV, Diesel and hybrid PV-Diesel water pumping systems for agricultural irrigation in Rwanda.The HOMER optimization software was used to evaluate both the environmental and economic viability of the proposed pumping systems by taking into account the variations of both the solar radiation and diesel price. Although this master thesis has used Bugesera (Rwanda) as case study, PVWP technology can be applied for agricultural irrigation purposes all over the world especially in rural areas applications leading to higher incomes and better living conditions for farmers. Results show that using PVWP systems for agricultural irrigation is the most profitable when compared to the rest two alternatives. It was found that the costs of producing one unit of energy by PV system are lower than the rest two systems. The HOMER results show that COE for solar PV, Diesel and hybrid PV-Diesel systems are 0.192, 0.367 and 0.289 $/kWh respectively. Finally the research found that by replacement of DWP with PVWP systems results to reduction of CO2 emissions by 14.48 tonnes over DWP and 1.25 tonnes over hybrid PV-Diesel systems yearly. Although, PVWP has more advantages of reducing CO2, there are also some disadvantages such as soil, farmland and grassland degradation and wildlife disturbance. However, Solar PV water pumping systems can contribute significantly positive to Rwanda economic development if all the identified barriers are well removed.