Overall seasonal energy cost analysis of smallholder pumped irrigation systems in the arid and semi-arid lands of Kenya
In Kenya, there has been a tremendous increase in the number of smallholder farmers using motorized pumps in their farming operations. The recent increase in uptake of pumps in irrigated agriculture is as a result of need to increase food production to meet the rising demand as well as modernize farming operations and has been met by various challenges. Among the challenges facing adoption of pumps is rising cost of energy particularly fuel used, diminishing energy reserves as well as lack of technical knowledge in selection, design and operation of these pumps. The result has been significant rise in cost of crop production in pumped irrigated agriculture. Combined with other factors such as market competition for agricultural produce and low market prices, the operation costs of smallholder pumped irrigated agriculture has as a result tremendously increased. The aim of this study was therefore to investigate the uptake rate as well as the cost of production due to pumps use in smallholder agriculture. This study was hence carried out in Kakuzi and Yatta divisions both located in the Arid and Semi Arid Lands and 80 smallholder farmers growing various horticultural crops such as French beans (Phaseolus vulgaris L), Tomatoes (Lycopersicon esculentum L) and Water melons (Citrullus lanatus) were considered. Face to face questionnaire as well as observational study was used to gather information. Detailed analysis of 10 pumps used in 10 sample farms was done to evaluate pumps working efficiency, fuel consumption rate and pumps water discharge under different operating conditions. This analysis helped in computing the overall seasonal energy cost of pumped irrigation. The study found out that despite the increase in cost of production as a result of pumping, farmers still adopted it with 80% of the studied population engaged in it. It emerged that high cost of fuel was the most limiting factor for 65% of the sampled population practicing pumped irrigation. Results indicated a big variation in fuel used to irrigate a unit piece of land from one farm setup to the other. In some farms growing similar crops, mean fuel (petrol) amount used to irrigate 1 hectare of land was in excess of 60L while in others, fuel used was as low as 5L. The overall seasonal energy cost in nearly all the farms investigated was over 50% of the total cost of production. The high value for overall seasonal energy cost could be attributed to several factors such as pump operating efficiency, fuel consumption rate and farm operating conditions (elevation, water conveyance distance and time of irrigation).
Key words: Energy use, pump performance, pumped irrigation, overall seasonal energy, cost (OSEC), Kenya