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), Keny

Farm water use efficiency assessment for smallholder pumped irrigation systems in the arid and semi-arid areas of Kenya

Water use efficiency for irrigated agriculture still remains low.  This presents a risky trend in the near future due to diminishing water resources as well as rising population demanding increased food supplies.  The objective of the study was to investigate pumped irrigation methods used by smallholder farmers in the arid and semi-arid land environments as well as assess the water use efficiency during crop production under usual farmer management.  The study was carried out in Mitubiri location of Kakuzi division and Kithimani sub location of Yatta division, Kenya.  Observational study during the field transect walks in the study sites identified methods of irrigation used by the smallholder farmers, water conveyance as well as application methods and the soil physical properties.  Questionnaires were developed and administered to 80 farmers in order to find out the socio-economic status of the people and the agricultural practices carried out.  A detailed study was carried out in 10 experimental plots set in the study areas.  Water losses during conveyance and application were assessed in the experimental plots.  Of the five farms where water conveyance was through secondary canals, the mean water conveyance efficiency was found to be 81.4%.  Water application efficiency in the ten blocks under different crops grown i.e. baby corns (Zea mays L.), French beans (Phaseolus vulgaris L), tomatoes (Lycopersicon esculentum L) and water melon (citrullus lanatus) in the months of April to July 2009 was assessed.  On average, water application efficiency ranged from 19.5% to 30 % for the crops assessed which was far below the recommended range of 65% for surface irrigation methods.  The study hence shows that there is a need to improve water use efficiency in smallholder irrigated agriculture in order to conserve water and ensure no shortages of water during the times of high water demand

Assessing performance of small-scale pumped irrigation systems in Sub-Saharan Africa: evidence from a systematic review

Small-scale irrigation (SSI) has significant potential to increase crop productivity in Sub Saharan Africa (SSA). Pumped irrigation systems are one of the technologies increasingly being used by smallholder farmers. The aim of this study was to systematically review evidence on the performance of SSI pumped systems, including motorized, treadle, rope and washer, solar and wind pumps. The study revealed a lack of standardization and use of a wide range of indicators to assess performance. Most evidence related to motorized pumps, these studies confirmed mixed levels of performance; studies relating to other types of pumped system mostly reported a positive impact, although the method of assessment used was critical. Studies reporting positive impacts tended to be those that used socio-economic based factors such as yield and profitability, whereas studies reporting mixed performance tended to be those that relied more on technically based indicators such as pumping and irrigation system efficiency. The analysis highlights the sensitivity of interpreting findings from different studies, and how caution should be exercised when comparing performance within and between different types of irrigation system. The implications for supporting policy development and identifying future research gaps are discussed