Irrigation system cost comparison model

Anjela Begmatova

The model presented in this thesis is a cost estimator, which was developed to assist growers, irrigation managers, and others with related interests with making system conversion decisions. It allows comparing costs for two irrigation systems of interest and calculating the potential gains/losses as a result of converting from one system to another. Model’s capability of calculating and comparing not only the total costs of each system but also annualized cost savings, such as costs per unit area and costs per water amount used for irrigation, permits focusing on profit maximization while minimizing the farming costs. Total farming costs, distribution uniformity (DU), irrigation efficiency (IE), and pumping plant efficiency (PPE) not only affect efficiency and profitability of irrigation systems but vary with irrigation methods as well. The results revealed that annual energy costs, cost/acre-year and total costs tend to decrease, and the cost/acre-in increases, when DU and IE increase, regardless the engine type. Electric pumps have advantages over the fuel pumps for all tested systems: even without improving DU and IE values, it is enough to upgrade the fuel pump to the electric pump to reduce system costs greatly. The results of sensitivity analysis showed that total costs (TC) had the same degree of sensitivity to all management factors (PPE, DU, and IE) regardless of the system and engine type. However, there were variations among the systems and pumps: TC were more sensitive to the parameters for the wheel-line than the center pivot irrigation system regardless of the engine type and, similarly, the costs had higher sensitivity to the parameters for the fuel pump than the electric pump regardless of the system. For the economic impact, TC were most sensitive to the labor costs and they were least sensitive to the pumping costs in all cases. However, the costs were more sensitive to changes in parameters for fuel pumps rather than electric pumps. Pumping costs showed the greatest variation and proved to be a dominant component of TC, which is explained by significantly different values of DU and IE of the two systems.

Irrigation system cost comparison model

Files and links (1)

Abstract

Metrics

Details