Solar Powered Irrigation Systems in Egypt

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This article is mainly based on information and documents that can be found at raseed-giz.com.

The Agricultural Sector in Egypt

About 54% of Egypt’s working population is employed in the agricultural sector, making agriculture key for the country’s development. However, agriculture in Egypt is aggravated by low rainfalls, relative low humidity (except for the coast) hot climate and the fact that water quality and volume of the Nile is constantly decreasing. Furthermore, 90 % of farmers work on lands of about 5 Feddan or less (1 Feddan = 0, 42 Acres). These factors entail that the Delta region has become less attractive for agricultural use and is instead being used to accommodate Egypt’s rapidly growing population. Therefore, and to meet the rising food demand; in the past 5 to 10 ears agribusinesses were forced to reclaim desert lands (the so called “new lands”) for agricultural use in the western desert and other desert areas. Yet, very high evapotranspiration and sandy soils usually require frequently water application to ensure that the water will not leach towards deeper soil layers where it will be unreachable for the crops. This makes irrigation agriculture inevitable in Egypt.[1]

Rising Fuel prices

Costs of diesel for irrigation systems are increasing sharply due to the lack of availability of diesel in the markets. Moreover, the use of diesel fuel is also more expensive in the “new lands” due to the remoteness of desert farms. Taking into account the costs of transportation of diesel, maintenance and overhauling of generators, using diesel will no longer be economically feasible or affordable for those farms in the near future. At the same time, Egypt’s exporters lose competitiveness in the international market due to crop losses that were caused by lack of irrigation. High CO2 emissions, immense diesel spills into the soil and risky long distance transportation of diesel to the farms are just a few ecological downsides of diesel operated water pumps. This makes the use of alternative energy sources vital to the development of Egypt’s agricultural sector.

Solar Irrigation in Egypt's Agricultural Sector

With 96 % of desert land, a high frequency of clear sky days and solar radiations ranging from 2000 kW/h in the north up to 2600 kW/h (m²/year) in the south, Egypt is one of the most potential countries in the MENA region for solar energy. The introduction of solar pumping irrigation technologies presents an opportunity to abandon non-sustainable and non-reliable fossil fuel powered generators. Fluctuations in both fuel prices and supply are prevented through the implementation of solar pump solutions. Using solar power guarantees stable and reliable on farm energy supply. Therewith, crop losses that result from insufficient irrigation are avoided. Furthermore, a cost calculation that was conducted for a remote desert farm in Bahareyia shows that one kw/h generated from diesel will cost the farm 1, 3 Egyptian Pound (LE) due to the cost of transportation, whereas 1kw/h generated from Photovoltaic (PV) will cost them only 0, 95 LE. With respect to irrigation, this implies that 1m3 of pumped water costs the farm 0, 35 LE when using diesel generators and 0, 19 LE when using solar energy. Using an alternative energy, such as Photovoltaic Systems, is thus also more cost-effective for remote desert farms.[2]

The Initiative 'RaSeed'

For this reason, the German development programme “Agricultural Water Productivity as Adaptation to Climate Change” on behalf of the German Federal Ministry of Economic Cooperation and Development (BMZ) called into life the initiative ‘RaSeed’.[3] The initiative aims to promote the use of Photovoltaic (PV) systems in drip irrigation farming in order to support cost-effective and sustainable agriculture. Therefore, the aim is to introduce high capacity solar operated water pumps - of up to a pump size of 100kW [4] - to the Egyptian agricultural sector. Furthermore, soil in the “New Lands” is mostly sandy, and water used for irrigation is ground water. Hence, it is crucial to use water efficient irrigation systems. RaSeed targets farm specific optimization of drip irrigation systems that enable maximum fuel savings and water efficiency by taking into account soil compositions and environmental conditions. In order to further the initiative, a Private Public Partnership (PPP) was established with two solar energy firms (Ashoff Solar and Juwi) that are supported by the multi-donor initiative ‘Powering Agriculture- an Energy Grand Challenge for Development’. Together with its partners, RaSeed establishes a network, providing high quality solar energy technology and training in Egypt.

Solar Pump Systems in Egypt

There are different options available when it comes to solar pump systems for irrigation. Generally speaking, the most commonly used PV cells are polycrystalline and monocrystalline cells. RaSeed opted for polycrystalline cells, although, monocrystalline cells are the most efficient ones. However, given that most of the farms in Egypt are located in remote desert areas, far away from on-grid systems and in-house cabling, polycrystalline cells have a better cost-efficiency ratio. Which solar pump system is best suited depends on various external factors. [5] Stand-alone solar pump systems for direct irrigation offer a very simple solution, with the pump and a solar inverter being directly connected. However, this system does not provide a backup power source. Therefore, three different and more advanced solar pump systems were made available by the partnering firms:

Battery Based System

To maximize independence of fuel price fluctuation, a so called Battery Based Hybrid System uses batteries in order to store any excess energy, making it a good option for full- day operations. However, the batteries and their mandatory replacement over time make this system also very cost intensive. In this setup kWp will cost between 33,000 LE to 47,000 LE, with the batteries making up almost half of these costs.

Solar Fuel Saver System

To avoid fluctuations in the irrigation schedule and to prolong irrigation hours one may prefer a hybrid system, which combines solar and diesel power. A so called solar fuel saver system avoids the aforementioned high battery costs; by using a controller that ensures continues operations. This system costs only around 16,000 LE per kWp and is therefore much cheaper than the battery based hybrid system. However, this system requires a constantly running diesel generator, despite solar energy being the main energy source.

Variable Speed Drive

The variable speed drive system is probably the most adequate for the Egyptian agricultural sector. This system uses a variable speed drive that connects and regulates PV Panels and the diesel generator. Depending on solar irradiation and the size of the power plant, the diesel generator can be turned off completely. Furthermore, the variable speed drive system is the most cost efficient, with 15,000 LE per kWp.

Pilot Projects

Three pilot projects that were initiated mostly at the end of 2014 are supported by the RaSeed initiative in order to promote and assess the feasibility and efficiency of solar energy irrigation systems under different conditions - hot weather, high soil salinity and sand storms. They are implemented at different locations across Egypt, allowing for a pluralistic analysis of solar irrigation systems in desert areas over time:
1. SEKEM- the Bahareiya Oasis
The solar powered irrigation system (45kWp) at the Bahareiya Oasis that was built at the end of 2014 is exposed to extreme heat (45-50 o C during summer time), which can have a negative effect on the PV panels. Also, due to the extreme remoteness of the farm, only solar energy can be used, implying that the fields can only be irrigated throughout the day (6 h during winter and 8 h during summer time).

2. WADI FOOD- in Wadi El Natroun
In Wadi El Natroun, a hybrid plant of 150kw/p (92Kw pump) was installed at the end of 2014. The irrigation plant is partially powered with diesel fuel (12%). Due to expansions in 2013, 14 % more water and 58% more fuel was needed, which lead to a stark increase in costs. Also, despite a strong water flow (115 m3/h), the water at the farm is extremely saline, and the fields are irrigated 16-18 h during summer time and 12 h during winter time, which could lead to salinization of the fields.

3. PICO- El Mansoureya
The desert farm at the outskirts of Cairo has implemented a central solar powered irrigation system with four pumps (288 kW) and a fuel saver system. The pumps reach 180 meters deep. However the existing generators are massively oversized, which has caused efficiency and distribution problems.

References

RaSeed


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[2]RaSeed is composed of the words Ra & Seed. Ra refers to the pharaonic god of the sun, which stands for energy and life, while a seed is the basis for all agricultural activities. At the same time, Raseed can be translated to ‘Credit’ in Arabic.
[3] To generate 100 m³ of water per hour, the solar pump has to be driven with around 70kWp. This requires the application of solar panels on an area of around 550m² to 800m².

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[4] For further information on irrigation pumps see: Study on Solar Energy vs. Diesel on Pilot Farm

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[5] For further information on irrigation practices in Egypt, see: Manual for Irrigation Practices in Egypt
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