TECHNICAL AND FINANCIAL PERFORMANCE OF SOLAR AND DIESEL-POWERED SPRINKLER IRRIGATION SYSTEMS AT UDS NYANKPALA CAMPUS, TOLON DISTRICT, GHANA

Abstract

This study compared and evaluated the performance and financial viability of solar and diesel-powered sprinkler irrigation systems used for vegetable production. Solar and diesel pumps were used to power the same sprinkler irrigation system and to irrigate cabbage during the first trial from 21stApril 2022 to 21 July 2022 and onion in the second trial from21st June 2022 to 21st September 2022. Primary data were sourced from field trials and computer based models were used to analyze them. Results show that cabbage required 132.5 mm supplemented to 334.1 mm effective rainfall and onion required 48 mm supplemented to 426.6 mm of effective rainfall. The Solar powered irrigation system (SPIS) pump sizing tool showed that solar pump had 25.9 m head with 34 % efficiency compared to the design discharge. In addition, hourly solar radiation data showed that it requires at least 50 W/m2 irradiance to operate. The SPIS Payback tool confirmed that solar initial investment is high compared to diesel powered system. Diesel powered irrigation system showed the better cost benefit ratio of 2.49, compared to SPIS (0.974) during the initial stage of the project. However, solar system overtakes diesel after nine years of the system life cycle. Also, solar system mitigates 1,049.55 Kg of CO2 per ha if irrigation is supplementary, while that amount can increase up to 4,198.18 Kg of CO2 per ha for total irrigation of vegetables farm during one growing season. Diesel engine operated irrigation pump emits carbon dioxide but solar pump was found to be an environmentally friendly technology. Implication stems from this research, being of interpretive and exploratory nature, raises a number of ideas for future researchers to tackle water pumping and economic emanated problems for sustainable production.