Field study in Machacamarca, Bolivia : An investigation on the effects of implementing solar powered irrigation

Abstract: This bachelor thesis consists of a field study conducted in the canton of Machacamarca close to La Paz in Bolivia. The global climate change has affected the weather in the area which has caused higher temperatures, irregularity in precipitation and unexpected frost. This has complicated the traditional cultivation methods and affected the harvest yield. One of the more important sources of income in the canton is the local diary that is processing milk from the local farmers. The main purpose of the thesis was to investigate the economic improvements that could be achieved in the canton with the implementation of an irrigation system driven by photovoltaic power, and to evaluate if it would be feasible. The simulation program Decision support system for agrotechnology transfer, DSSAT, has been used to simulate the cultivation and harvest of the two main crops for forage, alfalfa and barley. The required input data has been collected from the canton of Machacamarca and used to simulate the harvest yield for three scenarios, business as usual, ideal irrigation and limited irrigation calculated from the local conditions. A Matlab code based on numbers and parameters collected during the field study is used to create economical simulations from the different harvest results to receive economical results from several steps in the process. The final economical outcomes are compared to each other and to the cost for the chosen pump and irrigation system. Both scenarios considering irrigation show a stabilized and improved harvest yield, but only the third scenario is possible to implement in Machacamarca due to water restrictions in the area. This makes it possible to feed 0.47 more cows per hectare which will improve the farmers and the diary ́s income with 94.57 %. The water use for irrigation is 1.33 litres per square meter which makes the Shurflo 8000 water pump the most suitable option to provide water to the irrigation system powered by a 130 W solar panel and a battery. The investment cost for the system would go up to 6114 BOB equal to 883 USD and the system has a maintenance cost of 200 BOB every second year. This would make it economically feasible for the farmers to buy a system, but it would require investors or funding. With a payment plan the farmers would be able to pay off the investment without any problem.