Recently, we have been working in two areas: a motorcycle water pump for smallholder farmers and a solar panel pumping system and also developing a beautiful irrigation project very suitable for smallholder farmers.
Irrigation Project for smallholder farmers in Uganda
Irrigation Project in Eastern and Northern Uganda
Uganda is one of the counties most affected by global climate change and its geographic position in the far north of sub-Saharan Africa makes it especially vulnerable.
The availability of water is by far the most limiting factor for agricultural production in Uganda, as most farmers are reliant on rainfed agriculture. The availability of water for crops and livestock, especially in Uganda’s Eastern and North regions, is already being affected by changes in weather patterns. These periods of extreme weather variability are expected to continue in the coming years with severe consequences for rural livelihoods.
Uganda’s emerging economy is largely dependent on their agricultural sector, with over 85% of its estimated population of 42 Million living in the rural areas dominated by subsistence farming. This means that most of the country’s GDP and food security is in the hands of family run smallholdings.
With this in mind, it seems that the modernisation of agriculture is a critical path for empowering the poor and vulnerable members of society. Providing smallholder farmers with better extension services, quality inputs, and credit will elevate poverty by providing farmers with sustainable livelihoods.
Current farming communities
The Eastern and Northern regions of Uganda are home to approximately 18 million people. These largely rural regions are heavily reliant on subsistence agriculture, mostly comprising of small parcels of privately-owned land of one acre or less. Farmers mostly choose to grow low value crops such as maize, beans and cassava. These crops are often grown to provide families with both food and income. Sadly, they often fail to deliver both, due to poor yields and low market value. As a result, there is not enough food to feed the family or enough income to pay for schooling and healthcare when needed.
Farmers in Eastern and North Uganda are in real need of affordable irrigation system to help them cope with the changing climate that has led to many bad harvests in recent years. The United Nations Framework Convention on Climate Change defines climate change as “a change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods”.
For many years, farmers have been able to follow a relatively consistent weather pattern, which helped them decide when to complete their seasonal farming activities. However, recent changes to local climatic conditions now mean they often cannot rely on past weather patterns for their agricultural calendar, making it hard to consistently produce the qualities of food needed for their families.
The majority of Uganda sits within the drainage basin of the River Nile. Lake Victoria is the source of the White Nile, which runs north through Uganda to Lake Kyoga in the Central region and then into Lake Albert in the west, before heading north to the border with South Sudan.
Uganda is endowed with abundant water resources. Indeed, the total renewable groundwater is 39,000 Million cubic meters/year but only 259 million cubic meters/year are currently being withdrawn for agricultural irrigation purposes (Figure 1).
In many areas at Eastern and Northern Uganda the water table is between 1 and 20 meters below the surface, this huge aquifer of water is so close to the farmers, but they simply don’t have the technology to efficiently access it.
Figure 1: FAO. 2016. AQUASTAT website. Food and Agriculture Organization of the United Nations (FAO)
The project aims to promote a simple and cost-effective system that combines modern solar pumping technology with user-friendly gravity irrigation. This is ideal for smallholder farmers as it has low running costs and is simple to operate and repair.
The project will start by drilling a new borehole and installing a highly efficient DC Solar water pump which fills a water tank 6 meters above the ground. A single long flexible pipe will come out of the tank and be used irrigate the farmers plots. This means the farmers don’t have to turn the solar pump on and off as it will automatically refill the tank during daylight hours. They simply open the tap at the end of the long pipe and irrigate their crops.
To safeguard the project, the area where the tank and borehole are, must be protected by a fence, with only the project beneficiaries having access to this area.
In order to optimise the cost-effectiveness of the system, each borehole will fill a 5 cubic meter water tank, which will irrigate 8 acres of land.
1 acre is the average size of a smallholding in the area, so 8 farmers could share one irrigation system. This would mean scheduling the irrigation so that the single irrigation pipe is shared fairly between the families. In practice, 2 farmers would be able to irrigate each day, with all 8 acres being irrigated once in a 4-day rotation.
- Average static pumping head height: 16 m (52 feet) = 10 meters to surface plus 6 meters to the water tank inlet
- Daily flow needed: 4 cubic meters required per acre per day, as 2 acres are irrigated per day, 8 cubic meters will be needed daily
- Irrigating flow at a maximum distance (150 meters from the water tank):
- Pipe size 32 mm
- Total head 6 meters
- Flow speed: 0.6 meters/second
- Irrigating flow estimated: 0.5 liters/second
- Head loss: 2.5 meters
- Time spent to irrigate one acre: 2 hours
- Solar pumping system:
- Lorentz PS100HR7 pump with a 120-Watt Solar panel can pump 0.9 cubic meters per hour
Figure 2: Lorentz compass 2019
Figure 3: Solar Irradiation at Soroti Town, Eastern Uganda (1° North; 33° East)
The majority of farmers already know how important irrigation is to farming, as they utilise natural wetlands to grow rice. One of the major issues is that farmers have become used to NGO’s starting projects without the correct buy-in from the community. This has created many “white elephants” that often result in broken boreholes being abandoned and water tanks or water harvesting systems breaking and never being repaired. Farmers are sometimes waiting for another NGO to come along and repair the equipment, as they have not been empowered with a sense of project ownership as well as the technical and financial expertise to repair it themselves.
The most critical component of the project is to empower the local community, so they have a real sense of ownership over the irrigation system. To achieve this goal farmers must contribute to the initial cost of setting up the system. The level of contribution will depend on a farmer’s acreage. Once the project is up and running the farmers must repay a percentage of the remaining cost of the irrigation system. The farmers must also make monthly contributions to a community reserve fund that will be used to maintain and repair the system when needed.
The idea is that they must feel like they are purchasing this technology to improve their yields and ensure year-round production, rather than seeing themselves as lucky beneficiaries of an international pilot project.
The long-term aim of the project is to be fully sustainable by providing this irrigation system to the farmers under a low-interest long-term financing plan. Once the first community of farmers has utilised the system to increase their household food and income security, it is hoped that the project can be replicated with other communities within the Eastern and Northern regions of Uganda.
The total estimated cost of the project is 45 Million Ugandan Shilling (M. Ugx):
|Item||Cost (M. Ugx)|
|Bore hole + 110mm PVC well with casing + 6m well screen with packed pea gravel||20|
|6-meter high welded tower (including masonry work to fix)||7|
|5 cubic meters polymer water tank||2|
|Solar pumping system||12|
|Consumables + other expenses||4|
Cost benefit analysis
Currently most farmers plant twice a year, during the two rainy seasons. If they had access to irrigation technology, they could grow three or more crops per year. The simplest way to understand the financial benefit of this irrigation system is estimate the value of growing a third crop during the dry season.
- Prices: 2,500 Ugx per kilo (rainy season), 3,500 Ugx per kilo (dry season)
- Total yield per acre: 1 kilo per plant X 4,000 plants per acre = 4,000 kg per acre
- Gross profit: 4,000 kg per acre X 3,500 Ugx per kilo = 14 M. Ugx per acre
- Net profit: 14 M. Ugx per acre (sales) – 5 M. Ugx per acre (costs) = 9M. Ugx per acre
In total each acre under irrigation can provide a family with around 9 M. Ugx additional income, meaning a total of 72 M. Ugx will be generated for all the families involved in the project per year.
- Prices: 3,500 Ugx per kilo (rainy season), 5,000 Ugx per kilo (dry season)
- Estimated harvest: 3,000 Kg per acre (with irrigation)
- Gross profit: 3,000 kg per acre X 5,000 Ugx per kilo = 15 M. Ugx per acre
- Net profit: 15 M. Ugx per acre (sales) – 4 M. Ugx per acre (costs) = 11 M. Ugx per acre
In total each acre under irrigation can provide a family with around 11 M. Ugx additional income, meaning a total of 88 M. Ugx will be generated for all the families involved in the project per year.
This simple cost benefit analysis suggests that the yearly profit is considerably higher than the total cost of installing the irrigation system.
- The combination of modern solar pumping technology with the simple gravity fed irrigation systems makes this project particularly suitable to the local climate and the smallholder farmers in these regions.
- The cost benefit analysis shows that local farmers should already be taking the initiative to organise themselves into groups to ultilise this cost-effective technology. Sadly, due to there being a lack of knowledge, and access to equipment and finances they are not able to do so.
- Uganda now has many developing cooperative societies which should be encouraged to take up this technology, so that the benefits of cooperation can be seen within local communities.
- Hopefully, this will act as a catalyst encouraging farmers to also work cooperatively to purchase inputs, market their produce and add value.
Innovative Technology for Ugandan Farmers Project
Uganda’s economy widely depends on the agricultural sector. Over 85% of the estimated 42 Million Uganda’s total population live in the rural areas and depend mainly on Agriculture. Most of the farming activities take place in the rural areas. With that fact, it only right to say that Uganda’s food production base is widely dependent on the rural farmers.
Many regions in Uganda are practicing subsistence agriculture mainly because the land is owned by private individuals in small plots; so, the people choose what to do on their parcels of land. Because families practice subsistence agriculture on small plots of land, their target is to produce enough food to feed their families until the next harvest. In many cases, they fall short of their target.
The farmers in Uganda say they require an affordable irrigation system to help them cope with the changing climatic conditions that have been having drastic effects on their crop harvests. The United Nations Framework Convention on Climate Change defines climate change as a change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods.
For most farmers, the calendar for preparation of gardens, planting, weeding and harvesting have been reduced to a well-mastered pattern that is followed religiously every season. However, the changes in climate now mean they sometimes cannot rely on their past weather pattern if they expect good harvests. The future lies with the young Ugandan farmers and with agricultural practices and new technologies which are sustainable and protect the environment. Furthermore, young farmers should be given incentives to stay engaged in the farming sector.
There are some factors that determine the most suitable irrigation system. In this case, the price must be taken into consideration as well as the availability of the materials needed for the successful implementation of such a project. Many different on-farm irrigation systems are available, but a mobile setup that doesn’t require electricity and it isn´t possible to be stolen would be the most suitable for smallholder farmers. An innovation based on a water pump connected to a motorcycle could make this possible. The motorcycle engine powers a small, lightweight water pump, making the whole system quickly transportable.
This under-researched water pump is capable of irrigating up to one hectare in only 4 hours. Meaning that just one system can easily be shared among many farmers, thus significantly reducing upfront setup costs for individual farmers.
Why Connected to a motorbike.
A water pump has to parts; one part is the engine that produces mechanical action and the other is the hydraulic part that moves fluids.
The price would be less than half of the amount of a classic motor pump because this pump is using the motorbike engine, so the equipment consists of the hydraulic part only.
This project focuses on Bajaj 100 Boxer motorcycle to run the water engine because these motorcycles are cheap to buy, their spare parts are easy to get, and they are found in almost all homes in Uganda. In addition, this project would give an extra income to the owners and riders of these motorcycles in the rural countryside.
Can the Bajaj motorcycle be used for other farm operations when not being used for water pumping? E.g transport
Yes, it can be used for many things, but the idea is that the farmers do not have to buy one, only to hire one of the thousands boda-boda (It is like a motorbike taxi very common in Uganda) that are often around in Uganda. So, the farmer only owns the water pump, the pipes, and the rain gun, and the hired boda-boda contributing with the motorbike. The water pump should easily be able to connect to the bike.
In this way, the investment for the farmer is affordable, and don’t have to be worried about the motor engine maintenance. The boda-bodas use to stay hours in a crossroads doing nothing, so, they will prefer to agree with the farmer for a little money.
Also, all the farmers have a trusted boda-boda friend or familiar, and they use to hire him to transport the harvest.
Some homemade prototypes have been developed in Tanzania. However, they have not successfully been commercialized. In China, a company is now producing a low-quality plastic pump that only guarantees 72 working hours. However, to date, there has not been a real attempt at fully developing a permanent system. We have been testing that poor-quality one developed previously in China. It is not what we look forward to this project, but it´s a beginning.
These are the results at 4500 RPM:
maximum head: 53 m
rated flow: 15 cubic meters per hour (40 m)
Continuous work: After 1 hour it was smoking. The screws loosened.
Suction pipe diameter: 50 mm (2inch)
The water pump is not self-priming, and I have many problems with priming it due the connectors are inferior quality and leaked. Also, the non-return valve leaked.It is made of plastic (Noryl) except the motorcycle connector that is aluminium based.This motorcycle threaded connector is not stronger enough to keep the motor-pump still.It is not suitable for farmers with a limited water pump knowledge.It would be significant to Research a high-quality one that can be easily connected to the motorbike, Self-priming, and a good performance. We have no knowledge of another project, research or development about it.
What are the specifications of the pump we are proposing to promote? Head, discharge, etc.
The Bajaj Boxer 100 has Max. Power 8,2 HP so we can work with 5.5HP range Water-pump.For farmers is much better to choose a high-pressure pump because they usually are using a small pipe (for the cost)The water pump should be over 70 meters max. head and a rated flow of 18.000 lts.per hour. It must be self-priming, easily installed, high performance and durability (Iron or stainless steel).
What type of irrigation can use this innovation?
The only suitable irrigation system in Uganda, according to our experience, is one that you can remove when you finish irrigating. The water pump connected to a rain-gun is a proper system. Also, sprinkles can be used but the rain-gun reaches longer distance so can watering faster.
To calculate the water needed for the crops is required to know some specifical variables.
Using our empiric experience more than the evapotranspiration formulas, each irrigation would be of 7 mm. That is 70 m3 for 1 hectare.
There are many types of rain guns for instance this:
|40G-Raingun||42G-Raingun||Stand With connection pipe|
|Inlet Size||1.25″||1.5″||1.25″ / 1.5″|
277 L/min= 16620 L/hour so 1 hectare is irrigated in = 70000/16620= 4,2 hours.
If the plot is, for instance, 100×100 met. The rain gun must be shifted to 4 different positions, and keep it one hour on each.
The working pressure is 4 kg/cm2, and our pump pressure discharge is 7kg/cm2, so we have 3 Kg/ cm2 for head loss.
According to Hazen-Williams head-loss formula with 4.6 LPs( 277 Lpm) and 50 mm plastic pipe the head-loss is 15 meters each 100 meters so we can position our rain gun 200 meters distance from the river basin, allowing to many farmers have access to irrigation, not only the nearest to the source.
The working plan of this project is:
- To develop a feasibility study with a cost-benefit analysis for the business.
- To convert a high-quality water tractor pump into a motorcycle water pump.
- To set up standard motorcycle customization. The motorcycle would be the Bajaj 100 boxer, the most common bike in Uganda.
- Register the patent.
- To develop an irrigation system based on this technology that can support water Rain gun or sprinkles.
- To develop a feasibility study with a cost-benefit analysis for the farmers.
- Identify suitable young farmer groups around Uganda who are interested in taking up this new technology. Ugandan Agricultural Ministry through NARO (The National Agricultural Research Organization) and FAO Uganda are the contacts for introducing the innovation.
- To establish support stores in many cities around Uganda focused on rural areas.
- To set up a Marketing campaign.
The project involves four Phases.
The first one is a feasibility study. For two months, we must analyze the role of the stakeholders and if they are approachable, the financial support of the partners and other funding.
The Second Stage is to modify the water pump into the target. The idea is to find a self-priming tractor water pump or the hydraulic casing part of a motor water pump and make the modifications to connect it to the engine and to fix it to the motorbike chassis. Make a working prototype and register it in the patent registry. Our plan for this stage is to contact different water pump manufacturers in Spain, Italy, and Germany and get from them some ideas and water pump parts that could be useful. To develop two potential water pumps and test them in our water pump test-bed in Madrid.
The collaboration with a team of engineers at this stage would be priceless. We could be in permanent contact sharing ideas, technical solutions and solving together all the issues as they emerge. This Phase will last for seven months, since June till December 2018
In the third stage, the project goal is to complete a nine months pilot project with some young farmers associations, introduce them to the new technology and check the yield of their plots farmers in Bududa and Bulambuli. Those communities, among others, could be the target.
Finally, the fourth part of the project consists in the general assessment of the work, evaluating all the process, surveying the farmers, and analyzing the achievements. Consequently, this stage is time to research t, that is none other than to introduce the innovative technology in the Ugandan market. We believe that the market must do the job itself, but we shall help:
– Offering an affordable irrigation system and the technical knowledge for it to work.
– Developing a feasibility report with a cost-benefit analysis for the farmers.
– Setting up a Social Business providing irrigation consultant services and micro-finance credit to suitable farmers.
– Setting up a Marketing campaign.
– Setting up a network of stores around Uganda for the technical support, the post-sale service, and the spare parts.
Innovative compact floating Solar Pumping system
We partner Lorentz Solar Pumps Spain, and we can offer an integrated solar water pumping system for this application. The materials come from Spain. All PS2 systems use a unique DC brushless and sensorless motor named ECDRIVE. This motor is a perfect match for solar applications as it has a very high efficiency across its whole operating range. This is very different to a small AC motor where maximum efficiency is only achieved in a narrow operating band. Solar power is always changing through the day and depending on weather conditions. The LORENTZ ECDRIVE and PS2 have an average daily efficiency of above 90 %, most of other motors and controllers achieve 65 % with clear blue skies and much less when there is cloud cover. Next picture represents the idea:
The whole system would be floating on three floating balls. It is possible to change the position of the water pump to adapt it to any source, even shallow ones. This submersible pump doesn’t have to be primed, making the system easy to operate, therefore, suitable for smallholder farmers. In this way, it is not necessary suction pipe and check valve.
Only one unit of 280 Wat Solar Panel is enough, making the system easy to deliver. It is only 18 kg:
Nominal Max. Power (Pmax) 280 W
Opt. Operating Voltage (Vmp) 31.3 V
Opt. Operating Current (Imp) 8.95 A
Open Circuit Voltage (Voc) 38.2 V
Short Circuit Current (Isc) 9.52 A
Module Efficiency 17.11%
Operating Temperature -40°C ~ +85°C
Max. System Voltage 1000 V (IEC) or 1000 V (UL)
Module Fire Performance TYPE 1 (UL 1703) or CLASS C (IEC 61730)
Max. Series Fuse Rating 15 A
Application Classification Class A
Power Tolerance 0 ~ + 5 W
Cell Type Poly-crystalline, 6 inch
Cell Arrangement 60 (6 ˣ 10)
Dimensions 1650 ˣ 992 ˣ 40 mm (65.0 ˣ 39.1 ˣ 1.57 in)
Weight 18.2 kg (40.1 lbs)
Front Cover 3.2 mm tempered glass
Frame Material Anodized aluminium alloy
J-Box IP68, 3 diodes
Cable 4.0 mm²(IEC), 12 AWG (UL),1000 mm (39.4in)
Connector T4 series
Temperature Coefficient (Pmax) -0.41 % / °C
Temperature Coefficient (Voc) -0.31 % / °C
Temperature Coefficient (Isc) 0.05 % / °C
Nominal Module Operating Temperature (NMOT) 43 ± 2 °C
The whole system is mounted on a Hot-dip galvanised structure as the above picture. Allowing to move and install easily. Any of the components can be replaced quickly if necessary. Three expanded polystyrene balls fixed to the structure will enable the system to float. The solar panel can be swung to the most efficient position. The weight of all is less than 45 Kg.
The pump controller controls and adjusts the system operation and adjusts the output frequency in real-time according to the variation of sunlight intensity to realise the maximum power point tracking (MPPT).
PS2-150 is designed to be a complete solar water pumping system comprising of a specialised pump controller and carefully matched pumps. PS2 has eight sensor inputs that allow analogue and digital sensors to be connected. This combination of sensors with the powerful inbuilt software applications provides for full pump control and water specific applications.
The system also has an inbuilt Sun Sensor which measures the available irradiation and then makes decisions of what to do based on the available power. The system is configured on site using PumpScanner, an Android™ based App that the installer uses. Common configuration is done with three clicks, and there is full access to set system behavior based on additional sensor inputs.
The PS2 constantly records operational data and provides access to rich information that could be useful for the project evaluation.
Model : PS2-150
Pump motor rated power [kW] : 0.3
Affiliated pump Motor : ECDRIVE 150 – C
Max. DC input voltage [V] : 50
Min. recommended Vmp [V] : 17
Max.output current [A] : 22
The water pump is centrifugal Dc Lorentz PS2-150 C-SJ5-8.
Head max. 20 m
Flow rate max. 4,6 m³/h
Motor ECDRIVE 150-C
Maintenance-free brushless DC motor
Premium materials, stainless steel: AISI 304/316
No electronics in the motor
Rated power 0,3 kW
Efficiency max. 92 %
Motor speed 600…3.300 rpm
Insulation class F
Enclosure class IP68
Submersion max. 150 m
Pump End PE C-SJ5-8
Premium materials, stainless steel: AISI 304
Optional: dry running protection
Efficiency max. 51 %
Standards: 2006/42/EC, 2004/108/EC, 2006/95/EC