POWERING AGRICULTURE Sustainable Energy for Food. MASSIVE OPEN ONLINE COURSE Assignment One Solar Powered Irrigation Systems

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1 POWERING AGRICULTURE Sustainable Energy for Food MASSIVE OPEN ONLINE COURSE Assignment One Solar Powered Irrigation Systems

2 POWERING AG MOOC TEPMLATE FOR ASSIGNMENT ONE 3 Group s name Team East Africa 2 Chapter 1: Case study location The proposed solar powered irrigation system will be located in the following area: Continent Country Region Coordinates Short description about the socio economy of the region (max. 500 Africa Ethiopia Oromia Region, near Asella town - Kulumsa Agriculture Research Center Please provide the coordinates of your site: 8 0'58"N 39 9'26"E Kulumsa Agricultural Research Center is found at an altitude of 2200m a.s.l. It has a mean annual rain fall of 832mm and a mean temperature of 17 o C. The center is located near Kulumsa village with population size of 2,300.The heavy black clay soils, clay soils, clay loam soil and silty loam are the four major soil types on which the main staple crop wheat, highland pulses, oil crops, horticultural, fruits and forage crops are grown. The agricultural production system in the area is rainfed during the main rainy season (June- August) except for some summer crops and fruit trees which uses surface irrigation system (basin and furrow) from the collected reservoir. However the supply of water is not sufficient to irrigate large scale wheat production in the dry season. The centre is grid connected to hydro electric power. Due to frequent interruption, it has also a bigger capacity generator as back up. The centre is responsible for developing and releasing improved crop varieties multiply breeder seeds and assist farmers to increase productivity. Optional resize to view

3 POWERING AG MOOC TEPMLATE FOR ASSIGNMENT ONE 4 Chapter 2: Farming system (maximum 200 Farming system and water requirement 1. The site is known for growing wheat in the main rainy season. Barley, Faba Bean and Mustard are also grown as rotational crop. In the dry season most of the fields are left out of production except for small plots which are used to grow fruit trees (apple and avocado) and some vegetables. The apple plantation located on the downstream end of the reservoirs started last year. It uses basin type irrigation system water being supplied from the reservoirs by gravity. It is planned to expand on additional 5000m 2 area located above the reservoirs to promote apple production and increase the supply of plant material (seedling) to the farmers in the region; thereby increase their income. Apple is harvested twice in a year and can be a good source of income if they produce it in a small plot near their house. The purpose of this project is to develop an energy efficient irrigation system for the planned apple fields. 500 apple seedlings will be planted in 0.5ha area with spacing of 2.5mx4m in an area located in the upstream side of the reservoirs. As this new area is found on the upstream side of the reservoir, it is not convenient for gravity irrigation. Solar powered drip irrigation system is chosen for this project. Water requirement (maximum The two reservoirs have a total capacity of 70,000.m 3. One of the reservoirs is filled regularly with waste water from the malt factory which is full of impurities and not suitable for drip irrigation system, it is mainly used for surface & sprinkler irrigation. The other reservoir which has a capacity of 27,000m 3 is directly filled by river water weekly as the river water is diverted and mainly used by the malt factory. As per the agreement made with the malt factory, it is assumed that there is sufficient water for irrigation in the dry season given that there is no drought in the area which interrupts the river water supply as it happened last year. 2. The maximum crop water requirement of a matured plant is about 30l/day per plant. CWR, for 500 apple trees Months m 3 /month January 465 February March 279 April 300 May June 450 July 465 August September 270 October 310 November 450 December 465

4 POWERING AG MOOC TEPMLATE FOR ASSIGNMENT ONE 5 3. The water requirement of the plant can be met by rainfall during the rainy season for August production. Irrigation is required mainly for the dry season production. Since the rainfall data considers the total monthly, it does not mean that rainfall is uniformly distributed, irrigation may be needed in the middle, especially for months April, May and June.

5 POWERING AG MOOC TEPMLATE FOR ASSIGNMENT ONE 6 Chapter 3: Pumping head (height) calculation Pumping head (maximum Since the planned irrigation area is located on the upstream side of the reservoir, it is not possible to use gravity irrigation; it is required to pump water from the surface of the reservoir whenever irrigation is needed. Due to usage, the water level will decrease which increases the suction head of the pump from time to time The reservoir has a vertical depth of 6m. From the top of the reservoir up to the top end of the irrigation field, there is a maximum of 1.2m height difference. If two drippers each with a capacity of 8LPH are chosen per one tree, it is required 2.22LPS to irrigate 500 apple trees at a time. Maximum discharge required: 8m 3 /hr PVC pipe of diameter 63mm Elevation difference incl. Suction head: 7m Total pipe length:200m Pump type: surface pump with suction head of 6m Estimated Total head (including pipe, static head, main line, fittings...) = 20m

6 POWERING AG MOOC TEPMLATE FOR ASSIGNMENT ONE 7 Chapter 4: Sizing of the SPIS PV panel size (capacity) (maximum 500 P peak = 8.0 x H T x V day G total, day The mean daily global solar radiation for the design month of January is considered: G total, day = 7.6kWh/m 2.day H T = 20m V day = 15m 3 /day According to this equation, it takes a 316Wp PV generator to deliver water at the rate of 15 m³/d at a head of 20 m for a daily total global irradiation of 7.6 kwh/m²day.

7 POWERING AG MOOC TEPMLATE FOR ASSIGNMENT ONE 8 Chapter 5: Summary PV panel size (capacity) (maximum Our 316 W p is sized for the month of January in order to meet the peak demand and minimum dry season solar radiation (During the driest months of November, December and January) as indicated by the IWR graph. With this big size, the system will also be able to comfortably supply the demands of other months. Since the rainfall data considers the total monthly, it does not mean that rainfall is uniformly distributed, irrigation may be required during other months; especially for months April, May and June.