**1. Introduction**

Agriculture has been practiced for centuries and is regarded as the main source of food and income for the rural communities of Ethiopia [1], which accounts for more than

**Citation:** Assefa, T.T.; Adametie, T.F.; Yimam, A.Y.; Belay, S.A.; Degu, Y.M.; Hailemeskel, S.T.; Tilahun, S.A.; Reyes, M.R.; Prasad, P.V.V. Evaluating Irrigation and Farming Systems with Solar MajiPump in Ethiopia. *Agronomy* **2021**, *11*, 17. https://dx.doi.org/10.33 90/agronomy11010017

Received: 25 November 2020 Accepted: 21 December 2020 Published: 23 December 2020

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80% of the total population [2]. However, rainfed agriculture has frequently suffered from uneven distribution of rainfall and frequent drought shocks, leading to food insecurity of the poor rural communities [3,4]. In response to such recurrent challenges, smallscale irrigation has been considered as one of the main strategies to alleviate food and income shortages [5,6] and enhance the livelihoods of farmers in Ethiopia [7–12]. Smallscale irrigation often refers to distributed irrigation, small private irrigation, smallholder irrigation, or farmer-led irrigation [13]. In recent years, there is a keen interest in small-scale irrigation due to its cost-effectiveness [14] and sustainable management as compared to large-scale irrigation [13]. It is believed that Ethiopia has more than 6 million hectares of land that is appropriate for small-scale irrigation use [15] and ample water resources suitable for irrigation [15–18]. Nevertheless, irrigated agriculture comprises only 3% of the national food production, using less than 5% of the cultivated land for irrigation [4,19] due to various constraints. Xie et al. [13] depicted that Ethiopia has the potential to add about 1 million ha of land irrigated by small-scale irrigation systems by 2030.

Despite the considerably large potential for irrigation, there are several challenges for the wider adoption of small-scale irrigation in Ethiopia. Some of these challenges include temporal water scarcity [10], poor management of soil and water [7,11,20], lack of water storage facilities, limited opportunities for gravity-fed irrigation, lack of access to irrigation technology, high initial and operation cost of irrigation technologies, and limited capital investments [15,19,21]. On the other hand, limited rainfall and prolonged dry spells entail the need for the efficient use of both surface and groundwater sources, conservation agricultural (CA) practices, efficient water distribution and application systems [22–25]. It is evidenced that in Ethiopia, CA practice provides dual benefits of improved water [11,16,22,25–28] and improved soil conservation [29]. In terms of water application technology, the drip irrigation system is considered the most efficient and water-saving system [30,31]. CA in this study refers to the minimum soil disturbance with no-till practice, year-round organic mulch cover with grass, and diverse cropping in rotation, whereas CT refers to the traditional tillage with no-organic mulch cover and diverse cropping in rotation.

Groundwater is believed to be stable in the face of climate change as compared to surface water and would serve as a source of irrigation [15,32,33]. The role of efficient, labor-saving, and cost-effective water-lifting technologies is vital in unlocking groundwater potential for smallholder farmers [34]. Treadle pumps, rope and washer, pulley, and bucket have been used by smallholders in Ethiopia as a means of water-lifting technologies. However, these technologies are labor-intensive and only just used as a means of waterlifting beyond domestic use (e.g., drinking and cooking), and not for irrigation. Motor pumps (diesel or petrol) have been used by some farmers for irrigation but constrained due to high energy demand, limited access to fuel, and the alarming increase in the cost of fuel, and thus leading to increased risks in irrigated crop production [34]. In some urban areas, electric motor pumps might be feasible and used for urban agriculture. However, electricity access is rare for the rural community of Ethiopia [35]. In response to such challenges, several researchers suggested the use of solar pumps due to their high labor productivity, environmental sustainability, and use of renewable energy sources [36–38]. Ethiopia, as a tropical region, has ample solar energy [39,40] that can be captured for water lifting and pumping systems.

The MajiPump is a solar-powered water-lifting technology that was introduced in Ethiopia in 2017 by the Appropriate Scale Mechanization Consortium of the Feed the Future Sustainable Intensification Innovation Lab (SIIL). The solar MajiPump, a submersible pump, uses solar energy to extract water from wells and surface ponds. A solar panel is connected to the MajiPump by an electric cable driven by the direct current (DC). However, the discharge head and discharge capacity of the MajiPump is not known beyond the company specification. Evaluating the use of these pumps under field conditions and their impact on crop yields is critical for scaling and adoption of these technologies. Widescale use of efficient water applications in combination with improved crop and soil water management

technologies are vital for income generation and increase resilience in the face of climate change, and to reverse the decline of soil fertility. Such systems need to be tested for both vegetable production systems, which are becoming more popular due to demand for vegetables from urban markets and for high-value grain crops such as maize (*Zea mays* L.). Smallholder vegetable production is considered as a strategic approach to minimize children's death and stunting caused by malnutrition, which is a serious challenge in Ethiopia [41], by providing healthy and nutritious diets. Thus, the objectives of this study were to evaluate small-scale irrigation package: (1) MajiPumps (MP400 and MP200) for its discharge head and discharge capacity with different solar panels; (2) drip water application system with the common farmer's overhead irrigation practice using hose; and (3) CA with farmer's conventional tillage (CT) practice; in terms of water productivity and yields of key crops [garlic (*Allium sativium* L.), onion (*Allium cepa* L.), cabbage (*Brassica oleracea* L. var. captata), potato (*Solanum tuberosum* L.), and maize]. The results from this study would assist decision-makers and other stakeholders in scaling small-scale irrigation technologies and exploring groundwater potential in Ethiopia.

### **2. Materials and Methods**
