Solar Water Pumping (All You Need To Know)

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Water is life, and solar water pumping may be a way to harness that life in the future!

According to WWF, only 3% of the world’s water is freshwater, and 2/3 of that is frozen into glaciers making it a critical natural resource with a high risk of scarcity in the coming years.  Currently, 1.1 billion people lack access to freshwater.

Conversely, a US citizen is utilizing on average more than 380 liters of clean water per day. This is compared to 75 liters per day in Ghana. Most of that is for showering (20%), toilet flushing (24%) or washing clothe/dishes (36%), and leaks (12%).

You might think that those figures are already pretty large, however, this is only the tip of the iceberg. If we break down the total freshwater consumption, we find out that:

  • 11% is for domestic use
  • 19% is for industrial use
  • 70% is for agricultural use
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Solar Water Pumping
Freshwater is commonly used as a coolant fluid in industrial processes

If you are cultivating a vegetable garden, you certainly know that your harvests yield increases when watering the plants. Indeed, irrigated agriculture will produce on average 2 times more than rainfed agriculture (for the same plot size).

Currently, only 20% of the total cultivated land is irrigated, and it produces 40% of the global food stock.

Water is therefore the most critical input for agriculture and its consumption is expected to largely increase, as agricultural production is forecasted to expand by 70% by 2050, together with population growth.

Water and energy are closely related. Water can help us produce clean energy, this is hydropower (in man-made dams or in a river flow). Conversely, energy is required to extract water from a well.

The sun and the ocean
A billion-year-old couple: Water and Sun❤

One source of energy is available on every part of the planet, this is the Sun!

Let’s see how we can combine solar energy and water pumping in a solar pumping system to get water anywhere on the planet.


What Is Solar Water Pumping?

  • Extracting water from a source (well, pond, river, storage tank…) using the sun as your energy supply is called solar water pumping.

Let’s see how we came up with this system after thousands of years of water pumping.

The water wells are first thought to be used 8000 years ago. At this time water extraction was purely mechanical, for example with buckets and ropes.

water well
An idyllic water well

The first massive irrigation systems were developed by the Egyptians, more than 2700 years ago.

They took the form of an aqueduct. Aqueducts are man-made water channels, they take advantage of the difference in elevation between the source of water and its point of use (potential energy difference). This technique quickly shows its limits as it is dependent on the land’s elevation.

roman aqueduct
Pont du Gard, France, Roman aqueduct

During the same period of time, the Egyptians invented the first pumping system, the Archimed screw pump (wrongly attributed to Archimed). A screw-shaped surface inside a pipe elevates the water when a rotary movement is applied.

Archimed screw pump
Archimed’s screw pump, by Siberwolf

The energy needed to rotate the screw can originate from human strength, animals, or later, on motors powered by fossil fuels and electricity.

A Natural Source Of Energy To Power The Pump

Around 1000 years ago the world-famous Dutch windmill was the first system to use a natural source of energy for water pumping, the wind! This is wind-pumping.

windmills in the Netherlands
Windmills in the Netherlands, now part of the postcard picture, helped the country to dry its land below sea level

More recently, in the second half of the 20th century, solar cells were developed. They take advantage of the photoelectric effect (Einstein, 1905) to convert the energy of the sun into electricity.

Tremendous scientific research efforts over the last 50 years have brought to the world, highly efficient solar panels, that are now proven to be reliable and durable energy production systems.

The Birth Of Solar Water Pumping

In the late ’70s, the first-ever reported solar pumping system was introduced, coupling solar panels with a DC water pump.

Solar pumping is a versatile technology that can be applied to domestic, agricultural, and industrial use.

Solar Water Pumping For Agricultural Irrigation

In recent years, solar pumps are gaining traction due to the non-availability of electricity, the high cost of fossil fuels, and the global demand increase for water.

Solar water pumps are one of the most promising applications of solar energy.

Irrigation mostly occurs during the dry season, i.e. Summertime, when solar irradiation is at its maximum intensity. Consequently, solar energy production is also at its peak and more water can be pumped.

solar pump in the Philippines
Solar pump for rice field irrigation in the Philippines, picture from the National Irrigation Administration

Solar pumps are standalone systems, meaning they will operate with no connection to the electricity grid. Therefore, they are perfectly adequate for agricultural irrigation in remote areas.

Solar Water Pumping As A Circulation Pump For Domestic Use

If you have a campervan you might be familiar with the small circulation pump that brings water from the tank to your faucet.

This is a DC pump connected to your vehicle battery and you can run it completely on solar energy.

You can also equip your pool or pond with a solar-powered filtration pump.

You will find a handful of scientific literature showing that solar-powered water pumping systems are more reliable, and price competitive (cheaper!) compared to diesel water pumps for all use.


How Does Solar Water Pumping Work?

Your solar panel will transform the sun’s energy into electricity (DC), the electricity is then converted into mechanical energy by the motor of your DC water pump.

Schematic representation of a solar-powered water pumping system, courtesy of World Bank Group

Your solar pumping system consists of the following elements:

  • Solar panel array
  • Solar charge controller (MPPT type)
  • DC Water pump
  • Electrical safety equipment (fuse box, breakers)
  • Electrical wiring
  • Water storage (tank, cistern…)

You want to select them carefully to improve the overall efficiency of your solar water pump system Let’s take a deeper look into the components and choose the best one suited to your needs.

Don’t forget that your solar pumping system operates in DC (direct current) mode.

Choose The Most Efficient Solar Panel Array, Optimize Its Orientation, Avoid Shadowing

When operating solar pumps, you will use the sun as your energy source.

Our sun is beautiful, it is shinning all year long and offers an abundant source of energy everywhere on the planet. However, its intensity greatly varies during the course of the day, and also depends on climatic events (cloud, rain, snow).

Solar water pumping
A beautiful summer day!

The widely available silicon solar panels produce direct current (DC). They love direct sunlight, make sure that your solar panel is favorably oriented – the solar atlas provides useful information about your optimal tilting angle.

Choose A MPPT Solar Charge Controller

MPPT means Maximum Power Point Tracking This technology will help you to get the most out of your solar panel at all times.

The power of the sun varies during the day, and a cloud passing by could generate dramatic variation in your voltage and intensity output. This results in a difference between your solar panel output and the requirements of your DC water pump.

The MPPT will help solve this mismatch.

Choose A DC Water Pump

Avoid AC water pumps they will add complexity and reduce the total efficiency of your solar pumping system.

On the other hand, DC pumps are very efficient, on average they will use 50% less energy than AC pumps. Some models like the centrifugal pump have the ability to match the power output of your solar panel. Therefore, it will even operate in lower light conditions.

Store Your Water For On-Demand Use

Adding water storage capacities to your system is a must. You will gain flexibility and you will avoid installing batteries.

We advise you to install 2 to 3 days, worth of water. You could then use your water during the night and during cloudy/overcast days.

solar water pumping
Water cistern for cattle watering

In the end, the performance of your solar pumping system will depend on the:

  • Solar radiation availability at your location
  • Total head elevation of your system
  • Flow of water needed
  • Total quantity of water to cover your needs per day

How Much Is A Solar Water Pump?

Solar water pumps are extremely versatile systems, they are scalable from the microcirculation pump of your campervan to the massive pumping stations to meet the needs of a city.

The price of your system will therefore vary. Below are some price indications for 3 main applications of solar water pumping:

Application of solar pump systemPower of the DC pumpPower of the solar panel arrayWater pumping capacity per dayWater liftPrice
Campervan circulation80 W100 W500 liters3-5 meters+200 USD
Domestic pool or water well500 W +600 W +2 to 60 m3Up to 50 meters+1500 USD
Industrial and agriculturalSeveral kWSeveral KW+100 m3+100 meters+10k USD

Most of the solar pump systems require low maintenance, several case studies have proved that those systems are economically viable compared to diesel pumping and even to grid-tied water pumps.

You might want to ask yourself the following questions in order to design the solar pumping system that will meet your needs and fit in your budget:

  • What quantity of water do I need everyday?
  • When do I need water?
  • What water flow/pressure do I need?
  • How many meters the water has to be lifted from the bottom of the source to the head of the storage tank? (this is the total dynamic head elevation)
  • What is the capacity of my storage tank?
  • What is the quality of my water (could it damage the pump?)

Let’s study some real-life cases to closely estimate the cost of a system.

The Camper Van

One of the smallest solar water pumping systems that you can design is for a camper van or a boat water circulation pump. The needs are limited to a few hundred liters per day at low pressure.

A typical water circulation pump is rated at 60W of power and can be powered by a 100-watt solar panel.

Below is an average price breakdown of the components:

Solar panel110 USD
DC water circulation pump30 USD
MPPT solar charger25 USD
Wiring, electrical safety equipment35 USD
Total200 USD
Cost estimation of solar water pumping for a camper van

For more comfort you might want to connect the solar pump to your battery, therefore you can use it at night and even charge the battery with the excess of electricity produced by your panel.

VW campervan with solar panels
Adding solar panels on the roof of your camper van will help you to gain autonomy, you can charge your battery and run your water pump

The Pool Pump

You can save (a lot of) money with a solar pool water pump!

solar water pumping
Power your swimming pool pump with solar energy is not only good for the planet, but your wallet will also like it

Water filtration of a swimming pool is one of the most suitable applications for a solar pumping system.

  • Continuous operation is not needed
  • The quantity of water that will circulate everyday is fixed
  • Pumping is only needed during the day
  • The total head elevation rarely excess 2m
  • You will save money

Let’s take a look below at why you should switch to solar water pumping for your swimming pool.

For a 10 meters long, 5 meters wide, and 1.5 meters deep swimming pool (75 m3 ) it is recommended to have a pump capacity of 17m3/h. Usually, a regular AC water pump of 1.1Kw will do the job.

On average you need to filter the whole swimming pool every day. In our example, this would mean 5 working hours per day at full power of the pump.

DC solar pumps are 30% to 50% more efficient than their AC relatives.

Therefore, a 500W DC pump is the best for a swimming pool filtration pump. Depending on your location on the planet you might want to couple your DC pump with an 800W solar panel array.

For the same pump, you will need 700W of solar panel in Spain, 900W in Canada, and only 600W in California.

Below is an average price breakdown of the components :

6x Solar panel660 USD
500W DC pool pump690 USD
MPPT solar chargerIncluded in the dc pump kit
Wiring, electrical safety equipment100 USD
Mounting rail for solar panels150 USD
Total1600 USD
Cost estimation of solar water pumping for a swimming pool

Let’s see how much money you could save from switching to solar water pumping for your swimming pool.

 Regular AC grid tided pool pumpDC Solar pumping system
Running time per day5 hours5 hours+ (depending on weather conditions)
Max. power of the pump1.1 kW0.5 kW
Energy consumed per day5.5 kWh2.5 kWh
Cost of operation per day (22.26cents/kWh) California 20201.22 USD0 USD
The compared operational cost of AC grid-tied swimming pool pump and DC solar pumping system for a swimming pool in California

If we consider the cost of the solar energy production system alone around 850 USD. The payback time of the solar water pumping system is only 2 years.

Given the fact that your solar panels will produce for more than 25 years, you will actually save up to 10,000 USD over the lifetime of your panels!

The Deep Well Pump

Deep well pumping is the most common way to harvest water for daily human use. Solar water pumping will perform well for domestic, industrial, and agricultural well pumping.

You might want to equip your system with a water cistern that has2 to 3 days worth of consumption in case of bad weather that would reduce the global output of your system.

Let’s see what the cost would be of a solar pumping system to meet the needs of a family of 4 people.

A family of 4 people will consume on average 1 m3/day of freshwater. A 500W DC pump will cover the daily needs.

If the well is 30 meters deep and the domestic cistern 15 meters high from the surface, a typical domestic solar pump system will exhibit a flow of 10L/min.

Therefore the solar pump could only run 100 min every day at full power to meet the needs of the family.

Our energy source is the sun, the sunlight power will vary during the day consequently the power output (and the water flow) will also fluctuate.

In California, 600W of solar panels will cover your daily needs. Let’s break down the cost of your domestic solar water pumping system:

6x Solar panel660 USD
500W deep well pump600 USD
MPPT solar chargerIncluded in the dc pump kit
Wiring, electrical safety equipment100 USD
Mounting rail for solar panels150 USD
Total1510 USD
Cost estimation of solar water pumping for a domestic deep well

Let’s see how much money you could save with a deep well solar pump:

 Regular AC grid tided pumpDC Solar pumping system
Running time per day1.6 hours1.6 hours+ (depending on weather conditions)
Max. power of the pump1.1 kW0.5 kW
Energy consumed per day1.76 kWh0.8 kWh
Cost of operation per day (22.26cents/kWh) California 20200.39 USD0 USD
The compared operational cost of AC grid-tied well pump and DC solar pumping system for domestic water use

If we consider the cost of the solar energy production system alone around 850 USD. The payback time of the solar water pumping system is 6 years.

Given the fact that your solar panels will produce for more than 25 years, you will actually save up to 2,500 USD over the lifetime of your panels.

Note that the daily capacity production of the solar pump exceeds the needs of the family – this system could produce on average up to three times more. Extra water can be used for garden cultivation for example.

Note that the daily capacity production of the solar pump exceeds the needs of the family – this system could produce on average up to three times more. Extra water can be used for garden cultivation for example.

How High Can A Solar Pump Lift Water?

A 500W DC solar pump will commonly exhibit total dynamic pump head values of 80m to 100m.

The DC water pump is one of the main elements of your solar pumping system. DC water pumps are highly efficient systems (50% more efficient than the AC pump).

Like every water pump, their water flow is closely related to the pumping elevation. This is a critical parameter for deep well pumping.

Manufacturers commonly use the total dynamic pump head (TDH) to rate their systems.

To calculate your total dynamic pump head, you will need to know:

  • The static head – distance between the depth of your water pump to the top of your water tank)
  • The friction loss, related to the loss in pressure due to the friction of your water in your pipes. This is closely related to the length, the diameter and the configuration of your piping system (elbow, curves…). Estimate your friction loss here.
solar water pumping schematic
Schematic representation of a solar pumping system total dynamic head

For example, static head: 30 meters underground + 10 meters above the ground = 40 meters

Friction loss in 32mm pipe: 15m

Your total pump head is therefore 55m.


What Are The Best Solar Water Pumps?

DC pumps are the best pumps for a solar water pumping system. They are 50% more efficient than the AC water pump. Your best choice will be a DC centrifugal pump, let’s see why:

The main body part of your DC pump is built using high-quality low lead marine grade bronze and stainless steel. It is designed to be corrosion-free and to require low maintenance.

We can classify the solar water pumps into 3 types depending on their applications:

  • Submersible, for deep well.
  • Surface for shallow well, ponds, river, spring source, tank and in-line or floating pumps.
  • Floating or in line pumps for applications that doesn’t require a high lift, like water filtration in swimming pool, water circulation for a pond or in a house. 

DC water pumps are divided into 2 main groups based on their operation principle:

  • Centrifugal pump
  • Positive displacement pump

A positive displacement pump will use a set of pistons and diaphragm to force a specific quantity of water in a chamber and expulse it at the end of the outlet. They require more maintenance than the centrifugal pump.

Centrifugal pumps use a spinning impeller to force the water into the pipe, they can match their power with the output of your solar panel. They will still operate under low light conditions.


How Can I Get A Subsidy For A Solar Water Pump?

Solar water pumping is economically more viable over the long term than grid-tied water pumping. It does however require an extra investment compared to a regular system. This is mainly due to the cost of the solar panel.

India is one of the only countries promoting the installation of solar pumps for agricultural irrigation and offering subsidies to finance the system.

If you cannot get a grant for your solar water pump, you might still need public assistance to purchase your solar panels. Numerous countries offer incentives, in the form of preferential feed-in tariffs, or tax exemptions when you install solar panels at home.


Can You Run A Water Pump With Solar?

A solar panel array can run a water pump. The DC electricity produced by the solar panel will power a DC water pump.

The first system was introduced in the ’70s, the technology is now widely used in remote areas where there is no grid connection. The ever-decreasing price of solar panels is making solar water pumping technology accessible to all.

Systems can be designed from the smallest capacity circulation pump to the swimming pool filtering solar pump and even industrial systems for massive irrigation. 

Your solar pumping system will also operate differently compared to grid-tied AC pumping, as the sun is an intermittent source of energy its power fluctuates during the day. Consequently, the water flow of your water pump will also vary.


Can Solar Power Run A Well Pump?

Solar power can run any type of well pump.

There are 2 types of wells:

  • Shallow or surface well (up to 20 meters depth)
  • Deep well (more than 20 meters depth)

The submersible DC pump is the best for a deep well, it can lift water to high elevation yet with a strong flow.

Choose a surface pump for a shallow well.


How Deep Can A Solar Pump Work?

Solar water pumps for domestic use can work as deep as 100m, but they will perform better at depth of 30m. Keep in mind that the water flow is closely related to the depth of operation.

The deeper you need to pump the lower your water pressure will be.

Manufacturers usually provide the water flow of their system at different total pump head elevations.


5 Benefits Of Solar Powered Pumps

Here are the 5 benefits of a solar-powered water pump

  • They don’t require electricity grid connection (stand alone systems)
  • You will save a lot of money while operating them (cost competitive)
  • Solar pumps are versatile and maintenance free (from micro pumping to industrial/agricultural irrigation systems)
  • They are more eco-friendly as you will operate them with 100% renewable energy
  • They are energy efficient (up to 50% more efficient than an AC pump)

Final Thoughts

We might not all have a deep well in our garden, however, lots of our readers own a swimming pool, and solar pumping for pool filtering is probably one of the most economically viable applications of the solar pump.

We recommend you convert to solar water pumping now!

Kyle Browning

Kyle is a researcher and content specialist at Climatebiz. He has a strong interest in green technology, particularly in photovoltaic systems. Kyle believes in a future where everyone has affordable access to renewable energy, regardless of their race, religion, or social status. This ideology led Kyle to found Climatebiz - with the goal to provide free information for anyone, anytime.

1 Comment
  1. Reply
    MUHAMMAD ADAMU SHUAIBU Oct 23, 2021 at 1:43 pm

    I really like to have this water pump, but I don’t know how and where can I buy it .

    Leave a reply

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