Cutting costs for Duxton Nuts with solar responsive technology and dams functioning as a battery - Flow Power

Cutting costs for Duxton Nuts with solar responsive technology and dams functioning as a battery

Discover how Flow Power’s engineering advisory and smart technology could lead to
over $2 million in energy savings

There’s a lot of change happening out there. I recommend using Flow Power to consider your options before committing to a path.”

Peter Hermmann, Duxton Nuts

Case study overview

Flow Power’s unique solution proposes to power Duxton Nuts’ irrigation and walnut processing infrastructure, while reducing carbon intensity and lowering energy bills. 


Project Engineer

Simon Evans Quote Duxton Nuts

Yanco, NSW
Service Provided by Flow Power
Energy modelling & strategy
Reduce overall energy costs and increase carbon efficiency of operations
200 kW solar PV system generating 100% clean energy 

Duxton Nuts

Duxton Nuts manages a 576-hectare walnut grove in Yanco, NSW; home to 400,000 walnut trees that require regular irrigation, with energy for pumps provided by a limited capacity network and diesel generators.

Irrigation is one of the most important operations and is critical for the success of a walnut orchard, but pumping water into the dam for irrigation is an energy intensive process – one made more costly by Duxton Nuts’ reliance on diesel generators.  

Diesel is a carbon intensive fossil fuel that is also responsible for many harmful airborne particulates. Switching to a renewable alternative offers both cost and carbon benefits for Duxton Nuts. 

The challenge

Flow Power was approached by Duxton Nuts to investigate an alternative solution, with the aim of reducing dependence on diesel and cutting overall operational costs and carbon emissions.

The business is actively pursuing sustainable solutions and opportunities in order to achieve its Sustainable Development Goals. 

To assist in determining an appropriate power supply solution for the walnut grove, Flow Power conducted the following: 

  • Modelling of the current and future power requirements onsite 
  • A review of potential network infrastructure requirements for the site 
  • Network infrastructure indicative design 
  • A review of potential power supply options 
  • Techno-economic assessment of the identified power supply options 

When asked about potential power supply options, Simon Evans, Head of Engineering & Advisory at Flow Power, explained “Duxton Nuts was open to all options, including combinations of grid connection, biodiesel, small-scale wind, small-scale hydro, agricultural waste combustion, batteries and solar.” 

“We even considered several types of solar: roof-mounted, ground-mounted, floating solar on the dams, and mounted along water channels. We considered the cost, sustainability, and practical feasibility of them all.” 

“Solar generation, of course, isn’t 100% predictable, so the challenge is often to match consumption with generation.” 

The solution

“Practicality and cost-benefit considerations made rooftop solar a clear winner”, stated Simon, discussing the solution Flow Power proposed.  

“After thinking about the capital costs, operational costs and security-of-supply risks for the various options to meet excess demand, we settled on a standard grid connection along with some additional internal reticulation.” 

Flow Power’s solution involves installing a 200 kW solar PV system on site, coupled with smart technology to create a solar responsive pumping schedule.

This means that the water is preferentially pumped into the dam when there is an abundance of solar energy being generated. The water is then stored in the dam to be used as required. 

As a result, this allows the existing dam on the property to function as a battery, storing water that has been pumped using solar energy, which can be used at any time, regardless of whether the sun is shining. 

“The key insight was that we could use the dams to keep grid electricity costs down and make much more efficient use of solar energy. The dams store a supply of reserve irrigation water — around 2 weeks’ worth — that’s built up by using the pumps when solar energy is available.

“This reserve supply also acts as a buffer, allowing the pumps to drop a little behind when solar isn’t available, without hurting final water flows.”

The solution supports Duxton Nuts’ commitment to decarbonisation, while also reducing operational costs by shifting usage to periods when solar energy is abundant.

Peter Herrmann of Duxton Nuts has been impressed with Flow Power’s high levels of service and prompt feedback on design, advising other businesses to seek an energy solution from our team. 

The technology behind the project

Solar panels

The proposed 200 kW solar PV system is a cost-effective, sustainable way to power energy intensive irrigation pumps. 

Our team of engineers will install solar panels on site to generate solar energy and reduce reliance on the grid.  

The solar will be distributed from the roof of a new processing facility to all pumps and assets on site, via an internal high-voltage network solution proposed by Flow Power’s Engineering team. 

Learn more about Flow Power’s solar capabilities.

Solar responsive pumping

The solar responsive schedule uses timer controls and integrated communication technology to signal pumping assets to run during daylight hours, when the solar PV system is generating power. 

By shifting pumping to a solar responsive schedule, Duxton Nuts can maintain its operational output, while optimising the use of renewable energy to save money and reduce carbon emissions. 

The final result is the same – the dam is filled with water ready to be used for irrigation, but the power used throughout the process is cleaner, cheaper and more efficient. 


kWatch is an integral part of the solution Flow Power provided. 

Installation of this smart device enables communication between the solar system and irrigation pumps, to programme the solar responsive schedule. 

Providing customers with simple and accessible energy usage insights, kWatch enables faster decision-making, demand response, and can remotely power down non-critical operations at the click of a button.  

Learn more about kWatch.

The results

Lower energy bills

With Flow Power’s proposed energy solution, our team of energy experts estimate savings of over $2 million over a 20-year period. 

Compared to other sources of power, diesel generators use expensive fuel, have a high cost for spare parts and require regular maintenance.  

By installing a solar PV system and adjusting pumping times to periods where renewable energy is most abundant, Duxton Nuts can avoid high energy prices and reduce energy costs. 

Reduced carbon emissions

Through the solar simulation Flow Power conducted, we estimate 30% of all energy will be contributed by zero-carbon solar. 

Implementing a solar PV system reduces the demand for grid electricity, which is a mix of multiple energy sources including carbon intensive fossil fuels. 

By removing the need for diesel generators, Duxton Nuts reduces dependence on diesel, making significant savings in overall carbon emissions produced. 

Reaching sustainability goals

Duxton Nuts is actively pursuing sustainable solutions and opportunities as part of achieving Sustainable Development Goals. Read more here.

Flow Power is proud to be assisting Duxton Nuts in realising its energy opportunities, as we create the renewable future together.  

Find a smart energy solution for your business

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