Success Stories

Energy savings for geothermal heating systems with HES


 Headline Geothermal Installation HES UK

With the right components, the efficiency of a heating system with well installation can be increased and energy costs sustainably reduced. Geoquip Water Solutions in the UK recommends the combination with the High Efficiency System from Franklin Electric.

The increasing demand for renewable energies is causing the increasing numbers of geothermal heating systems in both the commercial and private sectors. Savings of up to 80 % compared to conventional fossil fuels and the reduction of CO2 emissions are among the advantages. In addition, there are various possibilities of financial subsidies from the legislators.

In addition to systems with geothermal probes and geothermal collectors, there is the option of operating a heating system with a well system. The two wells, the so-called suction and absorption wells, transport groundwater to the surface and use the heat of the groundwater as an energy supplier for water-water heat pumps, which extract the heat from the groundwater to heat rooms and process and drinking water in the house.

Since groundwater is an important resource for plants and living organisms, it must be recirculated. The pump in the suction well pumps the groundwater to the surface. After the thermal energy has been recovered in the heat exchanger, the now colder water is pumped back into the ground water via the absorption well. When positioning the two wells, it is important to consider the flow direction of the groundwater.


Immense savings potential through the right borehole pump

With geothermal heating systems, special care must be taken at the planning stage, because the potential savings over the lifetime of such a system are immense if the system is correctly dimensioned from the outset. The cost of purchasing and installing a typical geothermal heat pump system in an average house in the UK is around 14,000 to 19,000 pounds. A multiple of this costs the energy that is invested over the entire life of the system. It is therefore worthwhile to design the system ideally in order to achieve the maximum benefit.

The first thing to do is to make sure that the most efficient geothermal heat pump is used for operation, which also applies to the extraction pump in an open-loop system. This may sound obvious, but it makes no sense to have a „green“ geothermal heating system if the source pump is working around the clock and consuming far more electricity than necessary to move the water in the loop.

Therefore, the selection of the right components in particular is crucial. In an open-circuit system, the borehole pump is an important component of this. If the right pump for the job is not chosen here, the system cannot run effectively.


Permanent magnet technology as the key to outstanding efficiency

The key factor in these energy savings is the efficiency of the motor‘s permanent magnet technology. Instead of a short-circuit induction rotor, Franklin Electric uses a permanent magnet rotor design with integrated magnets. The total electrical rotor losses of a motor are eliminated, resulting in a significant improvement in efficiency. In addition, the PM motor has lower heat generation and requires less current to run at the same pump load. A frequency converter is required to operate a PM motor.


Remote control via App

The system is available in the sizes 4" 6", 8" and 10". Included are a submersible motor, a submersible pump, a frequency converter and the matching output filter.

The 4" system also offers the ability to remotely control and monitor system performance in real time using an App. Franklin Electric‘s support team can also access the system in this way to assist with problems or setting new parameters.


For Geoquip Water Solutions, the HES is the most energy-efficient solution

Mike Deed, Managing Director of Geoquip Water Solutions, has more than 30 years’ experience in the water treatment and solutions sector. He works with strategic partners to ensure customers receive the maximum benefit from their investment. He believes that the most energy efficient solution on the market is the High Efficiency Borehole System (HES), designed and manufactured by Franklin Electric.

» Here, Franklin Electric has set new standards in energy efficiency, because unlike most systems on the market, this system is not equipped with an - usually less energy-efficient - asynchronous motor, but uses an asynchronous NEMA standard permanent magnet motor, which has achieved motor energy savings of up to 21 % compared to standard asynchronous motors in numerous installations worldwide.«

The HES selection and sizing tool provided on the Franklin Electric website helps to select the right system. This tool can also be used to compare energy savings based on runtime and current energy prices. Systems typically pay for themselves within the first two years.

As with all things, being armed with the right information and components makes a difference. Given the long-term benefits that can be achieved through geothermal systems, it is definitely worth investing in the best.


This is how the thermal heat is obtained

The water-to-water heat pump transfers the thermal energy to a special refrigerant. This is initially liquid and evaporates when it absorbs the thermal energy. It then flows through a scroll compressor, which in turn increases the pressure and temperature of the medium. In the process, the steam is passed through two interlocking spirals. As one of the spirals moves eccentrically in circles, several gas spaces are created between the spirals, which become smaller and smaller towards the inside of the component, thus causing the pressure to rise. In the middle of the scroll compressor, the gases are finally pressed into the connected pipe. Here, the transported energy is transferred to the heating water. The refrigerant vapour cools down and liquefies again.

The efficiency of the system depends on the temperature difference between the design temperature of the heating system and the temperature of the environmental heat source. The groundwater is about 10 °C all year round. The compressor therefore does not have to use as much energy to raise the temperature, which makes the system very energy efficient.

How vineyards are irrigated with cost-saving using the 4" Solar HES


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In Spain, a vineyard is irrigated using the 4" Solar High Efficiency System. The customer’s initial skepticism quickly turned into enthusiasm about the enormous cost savings and the excellent support during commissioning.


Solar system for irrigation

The 4" High Efficiency System was installed in a customer‘s vineyards in central Spain for irrigation. The system consists of the following components:

  • 4" Encapsulated permanent magnet Solar motor 3 kW, 220 V
  • 4" submersible pump VS4
  • Variable frequency drive DrivE-Tech 3.030 Solar MP
  • flow switch

 The system was connected to 2 x 9 PV panels of 275 watts each.


Cost reduction through the HES

The local Franklin distributor Likitech assisted the customer during selecting the right system and commissioning. The customer was initially skeptical about using Franklin Electric‘s High Efficiency System because he had been using a competitor‘s system. However, knowing the high quality of other Franklin products, he was finally convinced. Also the promise that Franklin Electric‘s Technical Service would provide remote support during the commissioning of the system and would also assist the customer with any future problems, made the customer trust in Franklin. Ultimately, he is thrilled with the results, as the system is operating even more efficiently and cost-saving than expected. Franklin Electric is setting new standards with its High Efficiency Systems (HES) up to 250 kW, achieving energy savings of up to 21% compared to systems with asynchronous motors.

While it is also the combination of perfectly matched components, the decisive factor in the energy savings is the highly efficient permanent magnet motor technology, which almost completely reduces rotor losses and thus significantly motor current and heat rise. In many cases, reduced motor current equals less drop cable cross sectional area further reducing overall installation cost.

And in the case of solar systems, the MPPT algorithm and integrated voltage boosting (up to 2.2 kW) ensure that the number of solar modules can be significantly reduced, as the system output is maximized accordingly.

 Motorwirkungsgrad HES EN

How plants are irrigated from a well on Paros with the 4" Solar HES


1200 X 630 Px Solar HES On Paros Greece

A farm irrigates its crops with water from a 100-meter-deep well. This is pumped with the help of a 4-inch solar well system from Franklin Electric and solar energy from 9 solar panels.

Solar system for watering plants from a water tank

A farm on the island of Paros in Greece installed Franklin Electric‘s 4-inch High Efficiency System (HES) to pump water from a well application into a water tank for crop irrigation. The water is pumped from a depth of approximately 100 meters. 

Installed is a Solar High Efficiency System with the following components:

  • Encapsulated 4" Solar motor 200 V three-phase 2.2 kW with permanent magnet technology
  • 4" submersible pump VS2/20
  • Frequency converter Drive-Tech MINI Solar 2.015 MP
  • Level switch for the water tank

Energy savings of up to 20%

Franklin Electric is setting new standards in energy savings and efficiencies with its High Efficiency systems. Compared to standard asynchronous motors, savings of up to 20% have been achieved in the numerous systems already installed worldwide. It is the combination of perfectly matched components and their control: motor, pump, frequency converter and, if necessary, output filter harmonize perfectly from a technical point of view. First and foremost, however, it is due to the highly efficient permanent magnet motor. The technology eliminates rotor losses and thus significantly reduces current and self-heating. In many cases, the current reduction achieved leads to smaller cable cross-sections, which in turn has a positive effect on overall costs.

Setting up the system remotely

Even though the commissioning of the system is very intuitive thanks to the Franklin Electric app solution, it sometimes takes a bit of intuition and experience to find the right settings.
It‘s a good thing that Franklin Electric customers can rely on the assistance of the Technical Support in such cases! Since the system can even be controlled remotely via the mobile app, the customer was helped quickly.

In this application example, the system was commissioned in bad weather, not the best starting conditions for a solar system. However, Franklin‘s experts were able to adjust the parameters so that the motor turned and water was pumped despite the bad weather conditions. When the sun came out, the system ran optimally and pumped about 2.0 m³/hour. water, so that the water tank filled up quickly.

 Solar System Installation Including Flow Switch EN

Installation of the 4“ HES: When the filling of the tank has dropped to a defined level, the pump restarts independently to refill the water tank.



How the EH Dtm booster system controls flow and pressure on a poultry farm


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A poultry farm in England implements Franklin Electric’s EH Dtm multistage horizontal pump to reliably control and incrementally increase low flow and pressure to best suit the drinking water needs of young birds.

Control of flow and pressure

When raising chicks, it is enormously important to provide the animals with as much fresh water as they need, and this varies enormously as the animals grow. The biggest challenge here, especially during the growth period from two-day-old chicks to 34-day maturity, is controlling the flow of potable water to the production units. The pumps are typically installed in large on-site water storage tanks, from where the water is routed through the necessary filtration systems and drinking lines to the animals.

At the same time, the requirements for the new system were very high. Initially, the young animals require only very small, slow amounts of water, but the demand gradually increases, so the system had to be able to gradually increase the flow and pressure. As more and more emphasis is being placed on the energy balance of the systems when making new purchases, the new systems not only had to meet the high demands, but also be optimized in terms of energy by reducing energy consumption and increasing the efficiency of the system.

Pressure boosting system with 24/7 monitoring

Agri Management Solutions (AMS) in Hereford, England, provides water and irrigation services to poultry farmers. Working with Franklin Electric and its strategic partner Geoquip Water Solutions, the company‘s exacting requirements were met in full by installing a state-of-the-art booster system from Franklin Electric.

The EH Series multistage booster pumps are designed to meet all pressure boosting requirements. The stainless steel construction provides high performance in a variety of applications. The EH Series is offered in five flow rates and various power sizes (single-phase or three-phase) for a wide variety of applications.

The EH Series multistage vertical pumps are combined with the new Drive-Tech MINI inverter to increase the energy savings potential of these pumping systems. The Drive-Tech MINI uses innovative technology that ideally combines efficiency, ease of use, innovation and safety. In addition, the inverter enables 24/7 monitoring and control, which can even be done remotely via Bluetooth if desired.

Efficiencies increased, costs reduced

Ellis Whittal-Williams of AMS has worked with Franklin Electric and its strategic partner Geoquip Water Solutions and is thrilled. He says the units are completely reliable and also save a tremendous amount of money. Field reports show that the system saves an average of 40% energy compared to conventional speed control systems.

>> It is important to have a system that can handle a demand for very small, slow amounts of water when the birds are very young and allow them to gradually increase flow and pressure as the demand increases.  When the sun comes up and the birds wake up, the demand for water is higher. With the Drive-Tech MINI, we can run the pump constantly instead of stopping and starting it several times an hour. The pressure remains constant, resulting in smoother operation with less wear and tear and higher energy efficiency. <<

(Ellis Whittal-Williams from AMS)


More information about the EH Dtm series:

How orange trees are irrigated with the help of the Solar HES, controlled remotely


1200 X 630 Px Orange Tree Irrigation 4 Inch Solar HES MallorcaAn orange orchard on the island of Mallorca is reliably irrigated from a 90-meter-deep well using Franklin Electric’s High Efficiency Solar Well System. The system is installed and maintained remotely using the Franklin app.


Solar system for irrigation

A farm in Pui on the island of Mallorca, Spain, has chosen Franklin Electric‘s Solar High Efficiency System (HES) to irrigate an orange orchard with about 40 trees. The system is powered by six 330-watt solar panels. In combination with the HES, the approx. 2 kW solar field output delivers so much water that, in addition to irrigating the trees, the water requirements of a guest house are also met. Here, the pool is now also filled and the lawns irrigated.

Installed was a 1.1 kW Solar High Efficiency System with the following components:

  • 4" Encapsulated synchronous submersible Solar motor
  • 4" submersible pump VS4
  • Variable frequency drive DrivE-Tech MINI Solar MP
  • flow switch


Up to 21% energy savings

In times of rising energy costs, new systems put more and more emphasis on the best possible efficiency. Here, Franklin Electric has set a new benchmark with its High Efficiency Systems (HES) up to 250 kW. Compared to standard asynchronous motors, energy savings up to 20% have been achieved in numerous systems installed.

But how are these energy savings achieved?
It is the combination of perfectly matched components and their control: motor, pump, frequency drive and output filter. Most importantly, it is the submersible motor’s permanent magnet equipped rotor that eliminates rotor losses thus significantly reducing motor current and heat rise. In many cases, reduced motor current equals less drop cable cross sectional area further reducing overall installation cost. Excellent partial-load efficiency of permanent magnet motors allows the entire power range to be covered with only a few different motor sizes, thus offering important stock-keeping advantages.


Maintenance and control via app

A major advantage of the system is that it can be controlled remotely via the mobile app. The owners of the estate are only temporarily on the island, but can always monitor and control their pumping system themselves via the app.

Franklin Electric not only supports its customers in the run-up to an investment and helps them select the right system and associated components, but also stands by the customer‘s side during commissioning. Any problems that arise can also be analyzed and remedied remotely by Franklin engineers.

Thus, the commissioning of this system can also be done remotely. The local distributor Likitech and Franklin Electric service engineers guided the customer step-by-step through the installation of the drive and motor.

How the installation of the HES changed the farm life of Panhurst Farms in Morocco


2021 01 HES Installation Morocco

Panhurst Farms in Marrakech / Morocco installed a Solar High Efficiency irrigation system at the beginning of the year. The expectations for this system were exceeded, as the system works even more effectively than expected. It not only provides water, but also impacts the livelihood of many people, education, health and above all hope in one of the poorest areas in Morocco.


Agriculture against poverty in the dry continental climate of Morocco

Without sufficient resources, the endless cycle of poverty in Morocco continues. The agricultural project is dependent on support. Franklin Electric has therefore donated the technical equipment to operate the well on Panhurst Farm.

The installed 6" High Efficiency Solar System with 18,5 kW nominal power consists of the following components:

  • Encapsulated 6" Permanent magnet motor (max. 18.5 kW / 380 V / 3000 rpm)
  • Submersible well pump (VS 30/13, 50 Hz)
  • Frequency converter Industrial IP54 / 31 A
  • Output filter (Sinusodial IP54 / 100 Hz)
  • Flow switch

The system is operated in an existing well with a depth of 150 m and delivers approx. 30 m³/h of water. This is at least 210 m³ per day. On clear days this can be much more, because then the system continuously pumps water from the well. The High Efficiency System is driven by the energy generated by 80 solar panels.

The system was installed by a partner of Franklin Electric, that accompanied Panhurst Farms from the selection of the right system, through the installation of the individual components, to the final commissioning.

The system has been running stable and reliable since installation and has changed the way people work and live at Panhurst Farms.


"This self-running installation has saved us both precious time and much money that we would have otherwise spent on butane gas bottles, maintenance, and repairs on our vertical shaft-driven well pump. Your system has greatly decreased our personal stress load as well as sent our farm on a track toward sustainability. Thank you very much for your huge generosity and genuine care for us and those we serve." (Farr Family - founder of the farm)


Panhurst Farms

The Panhurst Farms agricultural project is located in a region of about 30 villages where poverty is high and is accompanied by illiteracy, limited educational opportunities and poor health.

Panhurst Farms aims to break the cycle of poverty by offering the rural population a real perspective by creating a working environment where employees receive income, mentoring and leadership responsibility. This way of sharing in prosperity through job creation minimizes dependency, preserves the dignity of each individual and empowers people to become agents of lasting change in their communities and society - one family at a time. The ultimate goal is lasting personal, social, economic and ecological change! Mentoring is tailored to the needs of each individual and promotes their talents.



Energy savings of 45 % in a waterwork due to HES installation


HES Installation Waterworks CZ EN

The initial situation

The Waterworks of the City of Brno (Brnenske vodovody a kanalizace a.s.) asked the company PUMPA a.s., a customer of Franklin Electric, to evaluate the existing pumping stations in the cities of Březové and Svitavou. The aim was to upgrade the existing system to the latest technical standard and to find possible energy saving potentials. When the team from PUMPA a.s. arrived on site, the first step was to select a well for the project, where the energy audit would be carried out and which would be representative of the cities Březové and Svitavou.

The selected well was equipped with a pump with a 45 kW asynchronous electric motor. The pump worked at an operating point of Q=54 l/s and H=34 m. The adjustments to the required parameters (Q&H) were carried out mechanically (throttled) at that time. The annual power consumption at this well was 320.244 kWh. This corresponds to 0.2459 kWh/m³ per unit of water pumped.


The solution

In cooperation with the experts from Franklin Electric, the situation was analysed and the innovative High Efficiency System was chosen, which enables energy savings of up to 20 %.

The system consists of a 304SS NEMA synchronous motor, a frequency converter (VFD) and a suitable output filter. The system is supplemented by a suitable submersible pump.

High Efficiency System for the well:

  • Rewindable permanent magnet submersible motor 22 - 30 kW
  • Stainless steel submersible pump
  • Variable Frequency Drive IP66 (VFD)
  • Sinusoidal filter IP54
  • flow meter

After evaluating all the advantages that the High Efficiency System would bring, the Waterworks decided to invest in the modernisation of the well. The equipment was installed by Franklin Electric.

The result exceeded expectations

It did not take long for the results of the newly installed system to become apparent, as energy costs fell continuously. The total annual consumption of electrical energy at the well decreased to 176.466 kWh and the energy consumption per unit of water pumped was 0.1355 kWh/m³.

The new system has therefore exceeded expectations, achieving a 45 % saving in total electrical energy consumption per m³ of water pumped compared to the previous equipment.

The reason for this enormous energy saving is partly due to the fact that the originally installed system had to be modernized, and also the set-up had to be optimized. The second reason is the outstanding efficiency of the Franklin Electric High Efficiency System. It is the combination of perfectly matched components and their control: motor, pump, frequency drive and output filter. Most importantly, it is the submersible motor’s permanent magnet equipped rotor that eliminates rotor losses thus significantly reducing motor current and heat rise. In many cases, reduced motor current equals less drop cable cross sectional area further reducing overall installation cost.

The return on investment for this project had been calculated for 2 years. However, due to the high energy savings, the entire investment for the well system was amortized after only 1.5 years.

EHsp Horizontal Self-Priming Multistage Pumps in action at the Civil Protection in Longare (Vicenza Italy)


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Franklin Electric is committed to man and nature, and so is the Municipal group of Civil Protection Colli Berici OdV in Longare. Franklin supports the association with equipment. A pump has now been installed to supply clean water to the group’s headquarters.


Clean water thanks to Franklin

The group of Civil Protection Colli Berici OdV needed a surface centrifugal pump and contacted Franklin Electric in Dueville with a request for a technical proposal. Franklin Electric had already supported the volunteer group in the past and immediately offered its help. In July 2020, after reviewing the situation, the Franklin Electric team installed a single-phase EHsp type self-priming pump with a 24-liter tank, pressure switch and pressure gauge.

The pump, which is connected to an existing pipe system, draws clean water from a well about 5 meters deep, which in turn is fed by a resurgent water vein. The pump was installed above the well in a soundproof and insulated cabin.

The water is used to wet the green area around the group headquarters and to wash the vehicles and equipment used during the activities. A water analysis is now organized to find out whether the water has drinking water quality. If so, it can be used to supply the hydraulic system of the headquarters.

Based on the technology of the horizontal multistage EH pump, the EHsp has a design innovation. A special elastic valve allows air that is present in the system to escape in less than 5 minutes and up to 7 meters of ascent. During start-up, this elastic valve, located in the first stage, opens to let the air escape from the system and suck water into the pump. When the pressure arrives at a certain point, the valve closes and the pump reaches the required performance. These functions make the pump a reliable partner on the premises of the Colli Berici group.

The headquarters of the Colli Berici OdV group is located in a 14th century house originally built by the Magistrato delle Acque of the Serenissima Republic of Venice to control and regulate the waters of the Bacchiglione (which flows below and next to the house) and the Tesina, which flows into the Bacchiglione at about 150 meters upstream.

Voluntary help in times of Corona

Since the Colli Berici OdV Civil Protection group is an integral part of the community in which it operates, during the recent Covid 19 pandemic, the volunteers kept the population informed of the government’s precautions and distributed protective masks, food and medicines to the elderly or needy people.

The group was contacted by some local tailors who donated washable and reusable masks. A sales campaign for the masks was then organized with the aim of raising funds for the purchase of two automatic defibrillators, which then were installed in easily accessible public spaces and are used in case of emergency (after appropriate training).

At Easter, during the shutdown, the group distributed the typical Italian Easter cake Colomba, and in agreement with the Municipality, to children under 6 years of age, who were particularly affected by the lock-down and were unable to meet peers. In gratitude, the children gave the volunteers pictures and drawings that now decorate the walls of the group’s headquarters.

The group has no direct source of income to finance the activities itself. Therefore, the members provide services that are not part of the standard activities defined by the Italian Civil Defense Office. These activities are carried out aside from the group in order to receive donations in return, which are used to purchase or maintain equipment such as safety equipment, tools or clothing.

For these reasons, the OdV Civil Protection Group Colli Berici is »proud to count on a partner like Franklin Electric, which has not only its technical competence but also a particular sensitivity to environmental issues, taking into account the needs of the municipality of Longare and the service ideals of the local Civil Protection Group«. the Mayor of Longare during the handover of the pump in July said.

Franklin motors maneuvering a submarine in 1000 meters under the sea


 Header EN

The technically unique submarine LULA1000 is the heart of the Rebikoff-Niggeler Foundation (FRN) , a non-for-profit organization for marine research based on the Island of Faial in the Azores/Portugal. On board are 5 Franklin Electric 4" encapsulated motors for the main drive as well as the maneuvers in all axes.

The interior has a special ergonomic design for maximum comfort during the long dives with an average duration of five hours. It has excellent maneuverability, even in difficult underwater terrain. Before the LULA1000 actually dives into the deep sea, multibeam sonar surveys are carried out to create bathymetric maps, which can then be used to identify areas of special interest.

LULA1000 is a stable work platform which was built according to the rules of the classification society Germanischer Lloyd (DNV-GL), who carries out yearly inspections and tests. These rules are very strict and have been established to guarantee a safe operation.

Looking for a cost-effective, yet reliable motor to drive the submarine’s positioning propellers, the designers approached Franklin Electric in 2009. Although the requested use lies well outside the scope of the original motor design, Franklin Electric engineers were appealed by the challenge to see their creation working on board of a submarine. With minimal modifications, Franklin Electric 4" submersible motors are now part of a 11-year success story.



The LULA1000 can take three people to a depth of 1000 m. The submarine is equipped with a large viewport of 1.4 m in diameter and the latest technology to collect oceanographic data and samples. It is perfectly prepared to take high-quality video and audio documentation about deep-sea animal life and behaviour. 


Franklin Electric motors on board

LULA 1000 is maneuvered by 5 submersible motors 2.2 kW each. The electrical winding design was modified to match the submarine on-board voltage, the mechanical design remained almost unchanged. Like the standard deep well motors, these motors were 100 % factory tested before being delivered to the building shipyard.The Franklin motors are used for the main drive and for the maneuvers in all axes. A planetary gear is used in the LULA1000 to drive a large diameter propeller. This is the main propulsion unit and has the advantage that the submarine can accelerate and stop quickly. Small, directly driven propellers are used for the lateral and vertical drive.

After more than 180 successful dives, these motors are now being replaced as part of a larger submarine overhaul.

In addition to the overarching vision of being able to offer clean drinking water to everyone, Franklin Electric also has the goal to contribute to the sustainability of the planet. Of course, this also includes the world’s oceans. Franklin is therefore happy to be able to support such projects.

Energy Savings was halved due to 6" High Efficiency System


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In times of rising energy costs, new systems put more and more emphasis on the best possible efficiency. Here, Franklin Electric has set a new benchmark with its High Efficiency Systems (HES) up to 150 kW. Compared to standard asynchronous motors, energy savings of more than 20% have been achieved in numerous systems installed.

This application example at a Waterworks Association in Germany proved that with the new method of operation with a 6" system the energy consumption was even halved. The reduction due to motor technology comes from a constant good efficiency throughout the entire performance range as well as perfectly balanced electronic components.

Franklin Electric installed and put into operation a 6" 15 kW Franklin Electric High Efficiency System, consisting of a 304SS NEMA synchronous submersible motor (3000 l/min), an IP66 Variable Frequency Drive (VFD) and an IP54 du/dt output filter.

Initial situation: ­

  • 10 stage 60 m³/h borehole pump with asynchronous submersible motor installed at 31 m below ground
  • Well diameter of 400 mm and depth of 50 m with continuous OBO filter
  • Minimum cooling flow alongside the motor is granted with the help of an additional cooling sleeve
  • The installation is remotely operated
  • Due to intake requirements as well as geological characteristics (water quality, well yield etc.) the pump has to constantly deliver 40 m³/h into a manifold pipe. Depending on additional wells being connected, the delivery head varies between 57 to 91 m. As these required duty points are not directly on the Q/H curve, the volume has to be throttled mechanically.
  • In two years observed the pump ran an average of approximately 200 hours per month with an input of P1 = ~20 kW (see graph 1).

New installation:

  • 5 stage 60 m³/h borehole pump (existing) with a Franklin Electric HES installed at 31 m including the existing cooling sleeve.
  • Due to limited space the electronic parts (VFD in IP66 and du/dt filter in IP 54) were mounted outside the existing cabinet directly to the wall.
  • At a rotating speed of 48.2 Hz, the newly chosen pump accurately meets the duty point I of 40 m³/h at 91 m (see green solid curve).
  • The rotational speed will be adjusted by the preset process reference 40 m³/h (read by existing flow control unit) in case of changing operational conditions/pumping heads.  Duty point II at 39.7 Hz for 40 m³/h at 57 m (see blue solid curve).
  • Due to the reduced rotation speed, the efficiency curve “moves” left resulting in an improved hydraulic efficiency compared to nominal load (see blue dotted curve).
  • These two duty points can now be achieved with an input of P1 = 9.5 and 16.2 kW respectively (see graph 2).


Energy savings through highly efficient system:

Due to this new method of operation, the pump now works at an average input of P1 = ~10.3 kW.  Thus, the energy consumption is halved (~ 80 % reduction caused by the speed control and ~20 % due to new motor technology).

The savings from motor technology are primarily due to the consistently good efficiency across the entire performance range and the perfectly matched electronic components (see graph 3).

The start-up went quickly and smoothly because of the custom-designed VFD software specifically developed by Franklin Electric.

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