Wind pumps for irrigating greenhouse crops: Comparison in different socio-economical frameworks

Abstract

A simple methodology was used to compare the economic feasibility of wind pump technology, solar photovoltaic pumping, diesel generators, and connection to the electrical grid to provide energy for pumping irrigation water in commercial greenhouses in Spain, Cuba and Pakistan (countries with different developmental backgrounds). The analysis took into account wind resources, distance to the grid, water storage tank volume requirements, and planting dates. Comparisons were made in terms of the levelised cost of energy associated with each system. For all three countries, if a grid connection was already in place, installing wind pumps would be economically unwise. Where no grid connection exists, the distance to the grid and the wind resource available are key factors to be taken into consideration when deciding between options: a 10% increase in the average wind speed is equivalent to a 20% reduction in the distance to the grid in terms of costs return. Finally, the water elevation has a major influence on the economic feasibility of wind pump technology, much more than, for example, on solar photovoltaic pumping technology. The results reveal that, generally, the critical factors to consider when making energy management decisions differ depending between countries. In Spain, the proximity of the electrical grid makes the connection to it the best option. In Pakistan, scarce wind resources are a serious limiting factor. Cuba, however, has good wind resources; water elevation, distance to the grid and water storage needed are the critical factors when determining the economic feasibility of wind pumping there.