Author Archives: Raeli Hydro

Solar submersible pumps are transforming how homes, farms, and institutions access water in off-grid and remote locations. By using the sun’s energy instead of grid electricity or diesel, they offer a cleaner, more reliable and cost‑effective solution for boreholes, wells and deep water sources. In this guide, Raeli Hydro explains how solar submersible pumps work, their key components, and why they are an ideal choice for modern water projects.

What is a solar submersible pump?

A solar submersible pump is a water pump designed to operate underwater, powered by electricity generated from solar panels. Instead of relying on mains power, the system uses sunlight to run an electric motor that drives the pump, pushing water from a borehole, well, river or storage tank to where it is needed.

Because the pump is installed below the water level, it is highly efficient at lifting water from deep sources. This makes solar submersible pumps especially suitable for:

• Domestic and rural water supply

• Irrigation and livestock watering

• Community water projects and schools

• Industrial and institutional boreholes

For clients working with Raeli Hydro, this technology offers long‑term savings on fuel and electricity bills while ensuring dependable water access, even in areas with poor grid connection.

Main components of a solar submersible pump system

A typical solar submersible pumping system consists of several integrated parts working together:

• Solar panels (PV modules): These capture sunlight and convert it into direct current (DC) electricity. The number and size of panels depend on the pump size, depth and daily water demand.

• Pump controller (or inverter): This smart device manages power flow from the panels to the pump. It optimises performance, protects the motor from low or high voltage, and can interface with level sensors in tanks or boreholes.

• Submersible pump: This is the unit installed underwater. It contains an electric motor and hydraulic section with impellers or a helical rotor to push water upwards.

• Cables, piping and fittings: Special waterproof cables carry power down to the pump, while pipes convey water to tanks, distribution lines or irrigation systems.

• Optional battery or water storage: In many designs, water is pumped into an elevated storage tank during the day, replacing the need for batteries. In some cases, battery backup is added for night or very cloudy conditions.

Raeli Hydro designs and sizes each component carefully so that the whole system works efficiently with local solar conditions and your specific water needs.

Estimated Prices of Solar Submersible Pumps

 

How do solar submersible pumps work?

While the technology behind solar submersible pumps is advanced, the working principle is straightforward. Here is a simple step‑by‑step overview:

1. Sunlight hits the solar panels
   During daylight, solar panels absorb energy from the sun’s rays. Inside each panel, photovoltaic (PV) cells convert this light into DC electricity.

2. Electricity flows to the controller
   The DC power from the panels is fed into the pump controller. The controller regulates voltage and current, ensuring the pump receives stable power. In systems with AC pumps, an inverter function converts DC to AC.

3. The submersible motor starts running
   Once there is enough power, the controller starts the submersible pump. The electric motor inside the pump converts electrical energy into mechanical energy, spinning an impeller or rotor.

4. Water is lifted to the surface
   As the impeller spins, it creates pressure that pushes water up through the rising main (delivery pipe). The water is delivered to a storage tank, header tank or directly into the distribution network or irrigation system.

5. Smart control and protection
   Many modern controllers include level sensors and dry‑run protection. If the water level in the borehole drops too low, or the tank becomes full, the controller automatically stops the pump to prevent damage and overflow. When sunshine returns and conditions are safe, the pump restarts.

The result is an automated system that pumps water whenever the sun is shining—without manual switching, fuel deliveries or complex maintenance.

Types of solar submersible pumps

Solar submersible pumps are available in different designs to suit various applications:

• DC solar submersible pumps: These connect directly to DC power from the panels via a controller. They are highly efficient and ideal for off‑grid systems.

• AC solar submersible pumps: These use an inverter to convert DC to AC, allowing the use of standard AC borehole pumps. This is useful where an existing pump needs to be converted to solar.

• Centrifugal submersible pumps: Use rotating impellers to move large volumes of water at moderate heads, suitable for shallow to medium‑depth boreholes and high‑flow applications like irrigation.

• Helical rotor (screw) submersible pumps: Use a helical screw inside a rubber stator, ideal for deep wells and high heads with lower flow. They are very efficient at lifting water from great depths.

Raeli Hydro helps clients choose the right pump type based on borehole depth, required flow rate, daily water demand and budget.

Key advantages of solar submersible pumps

Switching to solar submersible pumps delivers multiple technical and economic benefits:

• Lower operating costs: Once installed, the energy from the sun is free, drastically reducing or eliminating electricity and diesel expenses.

• Reliable in remote and off‑grid areas: Perfect for rural communities, farms and lodges far from the grid or suffering frequent blackouts.

• Minimal maintenance: With no fuel systems and fewer moving external parts, well‑designed solar pumps require less routine maintenance than generator‑powered systems.

• Environmentally friendly: Solar pumping reduces carbon emissions and noise pollution, supporting sustainable water supply solutions.

• Scalable and modular: Systems can be expanded by adding more panels or upgrading pumps as water demand grows.

For organisations prioritising sustainability and long‑term value, solar submersible pumps are a smart investment that pays back over time.

Work with Raeli Hydro on your solar pumping project

Designing a reliable solar submersible pump system requires accurate sizing, quality components and professional installation. Raeli Hydro specialises in:

• Borehole and site assessment

• Pump and solar array sizing

• Supply and installation of complete solar pumping packages

• Testing, commissioning and after‑sales support

Whether you need water for domestic use, livestock, irrigation or institutional supply, Raeli Hydro can engineer a tailored solution that maximises your sunshine and delivers dependable water every day.

If you are ready to reduce your pumping costs, cut fuel dependence and secure a sustainable water source, talk to Raeli Hydro about solar submersible pumps—how they work, what you need, and how quickly they can start working for you.

Jet pumps are a popular choice for drawing water from shallow and medium-depth sources, but many people don’t fully understand how they actually work. By Raeli Hydro

What is a jet pump?

A jet pump is a type of centrifugal pump that uses both an impeller and a jet (or ejector) assembly to move water. It is commonly used in domestic water supply, irrigation, booster systems, rainwater harvesting, and some industrial applications. Unlike submersible pumps, jet pumps are usually installed above ground and draw water up from a well, borehole, tank, or sump via suction.

Because they are versatile, relatively easy to install, and simple to maintain, jet pumps have become a go‑to solution for homeowners, farmers, building managers, and light commercial users who need reliable water pressure without placing equipment deep inside the water source.

Main components of a jet pump

Although designs vary, most jet pumps share a few key parts:

• Electric motor – provides the rotational power to drive the pump.

• Impeller – a rotating disc with blades that spins water and creates centrifugal force.

• Pump casing – houses the impeller and directs the water flow.

• Ejector/jet assembly – made up of a nozzle and venturi (throat) that create suction.

• Suction inlet – connects to the pipe coming from the water source.

• Discharge outlet – sends pressurised water into your plumbing or storage system.

• Foot valve and strainer – fitted at the bottom of the suction line to stop backflow and keep debris out.

Understanding these components makes it easier to see how jet pumps generate both suction and pressure at the same time.

Jet Pumps: Estimate Market Prices in Kenya

 

How jet pumps work: step-by-step

At the heart of a jet pump is a clever use of fluid dynamics, especially the Venturi effect and Bernoulli’s principle. Here’s a simplified step‑by‑step explanation of how a typical shallow‑well jet pump operates:

1. Priming the pump
   Before startup, the pump casing, ejector, and suction line must be filled with water. This “priming” removes air and allows the pump to create the vacuum needed to lift water. If a jet pump is not properly primed, it will run but fail to draw water.

2. Impeller creates initial pressure
   When you switch on the pump, the electric motor spins the impeller at high speed. Water inside the casing is flung outward by centrifugal force, creating a low-pressure zone at the centre of the impeller and a higher-pressure region at the outer edges.

3. Water is forced through the nozzle
   Part of this pressurised water is directed through a narrow nozzle inside the ejector. As water passes through the small opening, its velocity increases and its pressure drops. This is the Venturi effect in action: higher speed, lower static pressure.

4. Suction is created at the throat
   Just after the nozzle, the water stream enters a slightly wider section called the venturi throat. The high-speed jet causes a low-pressure zone that “sucks” water up from the well or tank through the suction line. In other words, the moving jet of water entrains additional water from the source.

5. Mixing and pressure recovery
   The water from the nozzle (called the driving or motive fluid) mixes with the water drawn from the source (the suction fluid) in the venturi. As the combined flow moves into an expanding passage, its speed reduces and pressure increases again. This recovered pressure is what allows the pump to push water into your household or system.

6. Delivery to the system
   The mixture then flows back into the pump casing, where it is further pressurised by the impeller and finally discharged into the delivery pipe. A portion of that water recirculates through the nozzle to keep the jet action going, while the rest goes to taps, storage tanks, or irrigation lines.

This continuous loop—pressurise, accelerate through the nozzle, create suction, mix, recover pressure—is what makes a jet pump so effective at lifting and delivering water.

Shallow-well vs deep-well jet pumps

Jet pumps can be configured for different water levels:

• Shallow-well jet pumps
  Typically used where the water level is no deeper than about 7–9 metres below the pump. The ejector assembly is mounted directly on the pump casing at the surface. These are ideal for shallow boreholes, wells, tanks, and sump applications.

• Deep-well jet pumps
  Used for water levels deeper than what a normal suction lift can handle. In this setup, the ejector (nozzle and venturi) is installed down in the well, while the motor and impeller remain at the surface. Two pipes run down: one sends pressurised water to the ejector, and the other returns the lifted water to the pump and into the system. Deep-well jet pumps can reach greater depths but are a bit more complex.

Raeli Hydro can help you select the right configuration based on your static water level, required flow rate, and pressure needs.

Advantages of jet pumps

Jet pumps offer several benefits that make them attractive for homes, farms, and small commercial sites:

• Above-ground installation for easy access and maintenance.

• No moving parts inside the well or tank, reducing risk of mechanical failure underwater.

• Ability to handle water with small amounts of sand or air better than many other pump types.

• Flexible configurations for shallow and moderate depths.

• Compatible with pressure tanks, controllers, and automation systems to deliver constant pressure.

For many users, this combination of convenience, reliability, and reasonable cost makes jet pumps a smart long‑term investment.

Choosing and maintaining a jet pump

To get the best performance from a jet pump, pay attention to:

• Correct sizing – match pump capacity and head to your demand and water level.

• Proper pipe sizing – undersized suction pipes cause friction loss and poor suction.

• Good installation – airtight joints on the suction side, a quality foot valve, and solid mounting.

• Regular maintenance – checking for leaks, monitoring noise and vibration, cleaning strainers, and ensuring the pump stays primed.

Raeli Hydro specialises in helping clients select, install, and maintain jet pumps for domestic, agricultural, and light industrial applications. With the right design and setup, a jet pump can provide years of dependable water supply and stable pressure for your property.

In Kenya’s water-scarce regions, borehole water pumps are essential for reliable groundwater extraction, powering homes, farms, and businesses. With Nairobi’s growing demand and rural borehole drilling booming, choosing the right pump ensures efficiency, durability, and cost savings. Raeli Hydro, your trusted borehole experts in Kenya, breaks down the main types of borehole water pumps, their features, and ideal applications to help you make an informed decision.

Submersible Borehole Pumps: The Gold Standard for Deep Wells

Submersible borehole pumps dominate Kenya’s market for their efficiency in deep boreholes (over 30 meters). Fully immersed in water, they push fluid upward using centrifugal force from multi-stage impellers, minimizing suction losses and energy waste.

Key advantages include quiet operation, high flow rates (up to 20,000 liters/hour), and longevity in harsh conditions like sandy aquifers common in Rift Valley areas. Popular brands like Grundfos SP series and Davis & Shirtliff offer 4-inch models fitting standard Kenyan boreholes, with heads up to 300 meters.

Ideal for: Large-scale irrigation in Kitui, domestic supply in Kajiado, or commercial use in industrial parks. Prices start at KSh 25,000 for 0.5HP units, scaling to KSh 150,000+ for 5HP heavy-duty options. Raeli Hydro recommends pairing with control boxes for overload protection.

Jet Pumps: Versatile for Shallow to Medium Depths

For boreholes under 30 meters, jet pumps (self-priming or ejector-style) excel by creating vacuum suction from the surface. A venturi jet assembly multiplies pressure, drawing water efficiently without full submersion.

These pumps shine in variable water tables, like seasonal fluctuations in Eastern Kenya, delivering 3,000–10,000 liters/hour. They’re easier to install and maintain than submersibles, with removable jets for cleaning sediment.

Pros: Affordable (KSh 15,000–50,000), corrosion-resistant stainless steel builds, and compatibility with solar or electric power. Drawbacks include higher energy use and noise. Raeli Hydro supplies Pedrollo and Lorentz jet pumps, perfect for small farms or apartments.

Solar-Powered Borehole Pumps: Eco-Friendly and Off-Grid Powerhouses

With Kenya’s sunny climate and rising electricity costs, solar borehole pumps—often submersible or surface types—are surging in popularity. They use DC brushless motors powered by PV panels, eliminating fuel or grid dependency.

Submersible solar models like SP 17 series handle depths to 150 meters, yielding 5,000–15,000 liters/hour for drip irrigation in arid Laikipia. Surface solar variants suit shallow wells under 20 meters.

Benefits: Zero running costs post-installation (KSh 100,000–500,000 upfront), low maintenance, and government subsidies via KOSAP. Raeli Hydro integrates Grundfos SQFlex hybrids, switching seamlessly between solar, grid, or generator for uninterrupted supply.

Centrifugal and Vertical Multistage Pumps: High-Pressure Boosters

Vertical multistage centrifugal borehole pumps stack impellers for extreme heads (up to 500 meters), ideal for deep, low-yield aquifers in Nairobi suburbs or coastal areas. They boost pressure for multi-story buildings or long-distance piping.

Horizontal centrifugal variants handle surface-to-borehole transfer, common in boost applications. Both types offer robust cast-iron construction for 24/7 operation.

Best for: Pressure boosting in estates or factories. Expect KSh 40,000–200,000, with Wilo and Lowara leading reliability.

Generator-Driven Pumps: Reliable Backup for Remote Sites

Petrol or diesel borehole pumps, typically centrifugal surface types, provide portable power for off-grid drilling sites or emergencies. High-volume models (10,000+ liters/hour) suit temporary irrigation in Turkana.

They’re rugged but fuel-thirsty, requiring servicing every 200 hours. Raeli Hydro stocks Honda and Yamaha units as backups to electric/solar systems.

Choosing the Right Borehole Pump: Key Factors from Raeli Hydro

Selecting the best type of borehole water pump hinges on depth, yield, power source, and budget:

Match pump size to borehole diameter (3–8 inches standard in Kenya). Factor in Total Dynamic Head (TDH) for pipes/fittings.

Why Partner with Raeli Hydro for Your Borehole Pump Needs

As Kenya’s borehole specialists, Raeli Hydro offers free site assessments, installations, and 2-year warranties on top brands like Grundfos, Davis & Shirtliff, and Pedrollo. We optimize for energy efficiency, cutting your costs by 30%.

Contact Raeli Hydro today for custom quotes, solar integrations, or maintenance. Secure your water future—drill, pump, prosper!

Borehole water is a valuable, reliable source for homes, farms and businesses, but it is rarely safe to use straight from the ground. It can contain sediments, excess minerals, pathogens and chemical contaminants that affect taste, stain fixtures and, most importantly, threaten health. In this guide, Raeli Hydro explains how to treat borehole water step by step so you can enjoy clean, safe and great‑tasting water for drinking, cooking and everyday use.

Step 1: Test your borehole water

Before you install any treatment system, you must know what is in your water. A professional laboratory test will typically check for:

• Physical parameters: colour, odour, turbidity, and total dissolved solids (TDS).

• Chemical contaminants: iron, manganese, fluoride, nitrates, hardness (calcium and magnesium), salinity and pH.

• Microbiological contaminants: bacteria such as E. coli and coliforms, and sometimes viruses and parasites.

These results guide the design of the right treatment solution. For example, high fluoride requires different treatment from high iron or high hardness. At Raeli Hydro, water analysis is always the starting point for any borehole water treatment project so that you invest in solutions that actually work for your specific borehole.

Step 2: Pre‑treatment and filtration

Most borehole water carries sand, silt and other suspended particles from the aquifer and plumbing. The first line of defence is mechanical filtration:

• Sand or multimedia filters remove larger particles that can clog pipes and damage pumps and membranes.

• Cartridge sediment filters polish the water further, capturing fine sediments and rust.

Pre‑filtration protects all the stages that follow, especially sensitive components like reverse osmosis membranes and UV lamps. In many installations, Raeli Hydro positions the filters immediately after the storage tank or pressure vessel so that all downstream water is already physically clean.

Step 3: Correct pH and manage hardness

Many boreholes produce either slightly acidic or very hard water. Untreated, this can corrode pipes, stain fixtures and scale up geysers and appliances. Typical solutions include:

• pH correction using dosing pumps and chemical tanks to bring the water into a neutral, stable range.

• Water softeners using ion‑exchange resins to reduce calcium and magnesium, preventing scale in pipes, boilers and industrial equipment.

By conditioning the water at this stage, you extend the life of your plumbing infrastructure and improve the performance of subsequent treatment processes.

Step 4: Remove dissolved contaminants

Once the water is physically clear and chemically balanced, you can target dissolved contaminants that affect safety and taste. Common technologies include:

• Activated carbon filtration to reduce chlorine, organic compounds and odours, and improve taste.

• Reverse osmosis (RO) systems to remove excess salts, fluoride, heavy metals and many other dissolved solids using a semi‑permeable membrane.

• Specialized media filters for specific issues, such as iron and manganese removal.

For households and businesses dealing with high TDS, fluoride or salinity, a properly sized RO plant designed by Raeli Hydro can transform brackish borehole water into high‑quality potable water suitable for drinking, cooking and even bottling.

Step 5: Disinfection for safe drinking water

Even clear water can harbour harmful microorganisms. Disinfection is therefore essential if the water will be used for human consumption. The main options are:

• UV sterilisation: ultraviolet light kills bacteria and viruses without adding chemicals or changing the taste of water.

• Chlorination: liquid chlorine dosing or tablet systems provide residual protection in storage tanks and distribution networks.

Many systems combine these methods, using UV as the primary disinfection step and low‑dose chlorine to maintain safety in pipelines and storage.

Step 6: Storage and distribution best practices

Proper treatment must be supported by good storage and distribution practices. To keep treated borehole water safe:

• Use closed, food‑grade tanks protected from direct sunlight to limit algae growth.

• Clean and disinfect storage tanks periodically to remove sludge and biofilm.

• Ensure pipes, taps and fittings are non‑corrosive and regularly inspected for leaks or contamination points.

Raeli Hydro designs complete systems from borehole to tap, ensuring that the quality achieved at the treatment plant is maintained all the way to the user.

Ongoing monitoring and maintenance

Water treatment is not a one‑time event. To keep your borehole water consistently safe and compliant, you should:

• Schedule periodic water quality tests to confirm that the system is performing correctly.

• Replace filters, membranes and UV lamps according to manufacturer and installer recommendations.

• Check and calibrate dosing pumps and control panels regularly.

With a maintenance plan from Raeli Hydro, you avoid unexpected failures, protect your investment and ensure your borehole remains a sustainable, long‑term water source.

Why choose Raeli Hydro to treat borehole water?

Treating borehole water requires technical expertise, quality equipment and a clear understanding of local water chemistry. Raeli Hydro specialises in borehole water analysis, treatment system design, installation and after‑sales support for homes, estates, farms, schools and commercial facilities.

Whether you need a compact domestic purifier, an industrial‑scale RO plant or a complete treatment and storage solution, Raeli Hydro will recommend the most efficient, cost‑effective approach for your specific borehole.

If you are searching online for “how to treat borehole water” or “borehole water treatment in Kenya”, partner with Raeli Hydro to turn your raw groundwater into a safe, dependable and high‑quality water supply.

How hard water interacts with your washing machine may be invisible at first, but over time it can seriously shorten the life of the appliance and increase your running costs. By understanding the faults it causes, Raeli Hydro can help you protect both your machine and your laundry.

What is hard water?

Hard water is simply water that contains high levels of dissolved minerals, mainly calcium and magnesium. As this mineral‑rich water is heated, sprayed and drained through your washing machine again and again, it leaves behind solid deposits known as limescale. These deposits gradually coat internal parts, restrict water flow and interfere with how detergents work, setting the stage for multiple faults.

How hard water affects key washing machine parts

Inside every washing machine are components that rely on clean, free‑flowing water to function efficiently. Hard water steadily attacks these parts:

• Heating element: As limescale builds up on the heater, it acts like an insulating blanket. The element must work harder, use more electricity and run hotter to reach the same temperature. Over time this can cause overheating, tripping, or complete element failure.

• Pipes and hoses: Mineral deposits cling to the inner surfaces of pipes, hoses and internal channels. This reduces water flow, affects filling and draining times and can eventually cause partial blockages.

• Valves and pumps: Inlet valves, circulation pumps and drain pumps can become coated with scale and detergent residue. This makes them noisier, less efficient and more prone to seizing or burning out.

• Drum and tub: Limescale, soap scum and dirt can form a rough, chalky layer on the drum and outer tub. This harbours bacteria, leads to unpleasant odours and makes the machine much harder to keep hygienic.

• Seals and gaskets: Soapy residue mixed with minerals collects around rubber door seals and gaskets. This can cause black mould, leaks and, in the worst cases, damage to the rubber itself.

Each of these effects on its own might seem minor, but together they steadily cut performance, increase energy use and push the machine toward early breakdown: Washing machine repair in Nairobi

Common faults caused by hard water

Over time, the impacts above turn into very real, day‑to‑day faults. Typical problems linked directly to hard water include:

1. Poor heating and error codes
   A scaled‑up heating element struggles to heat water efficiently. You may notice wash cycles taking longer, lukewarm water even on hot programs, or error codes related to heating. Eventually, the element can fail completely, requiring a replacement.

2. Longer cycles and incomplete rinsing
   Restricted water flow through scaled pipes and valves can make filling and rinsing slower. The machine may extend programs automatically to compensate, or stop mid‑cycle because it cannot reach the correct water level, leaving clothes soapy or still dirty.

3. Pump and drainage issues
   When limescale and residue reach the pump, it has to work harder to move water. This can cause noisy operation, intermittent draining or total pump failure. In serious cases, water may remain in the drum, and the machine will refuse to spin.

4. Leaks and mould around the door
   Mineral‑rich, soapy water leaves deposits on rubber seals, encouraging mould growth and making the rubber less flexible. You might see black marks, smell mustiness, or notice small leaks around the door.

5. Bad smells and bacterial growth
   The combination of hard water minerals, detergent residue and body oils provides an ideal breeding ground for bacteria inside the tub. This leads to persistent odours, grey sludge in hidden areas and clothes that don’t smell fresh even after washing.

6. Noisy operation and increased wear
   As components are forced to work harder against scale and restricted water flow, they tend to become noisier and wear out faster. Bearings, pumps and valves all experience extra stress, so breakdowns become more frequent and the overall lifespan of the machine drops.

7. Reduced cleaning performance and fabric damage
   Hard water doesn’t only affect the machine; it also weakens the cleaning process. Minerals react with detergent, reducing lather and cleaning power. Clothes can come out stiff, dull and rough, with soap marks or white streaks. Fabrics wear out more quickly and colours lose their brightness sooner than they should.

Why treating hard water matters

For households and laundries in hard water areas, ignoring the problem usually means:

• Higher electricity use, as the machine works harder to heat and move water.

• More detergent and fabric softener needed for the same cleaning result.

• More frequent repairs, especially of heating elements, pumps and valves.

• A shorter overall lifespan for the washing machine.

By addressing water quality, you’re not just protecting an appliance; you’re protecting your budget and your clothes.

How Raeli Hydro can help

As a water‑treatment specialist, Raeli Hydro focuses on preventing these faults before they happen. Solutions may include:

• Point‑of‑entry water softeners to remove hardness minerals before they reach your washing machine.

• Inline scale‑reduction devices for targeted protection of laundry appliances.

• Professional advice on compatible detergents and regular descaling routines.

With the right hard water treatment in place, your washing machine runs more efficiently, your laundry looks and feels better, and costly breakdowns become far less likely. For homeowners, landlords and commercial laundries alike, working with Raeli Hydro to control hard water is a smart way to extend machine life and maintain consistently high wash results.