Energy Savers
Darling Downs

Cotton and Sorghum Farm

Implemented
10
Energy Savings
21.6
Savings
7,182
Industry
Cotton
Irrigation
Flood
Pumps
Bore
Technology
Pump upgrade
Capital Cost
$28,117

Farm Profile

A recent Energy Savers audit showed that further improvements in energy efficiency could be achieved from the installation of two new pumps and four 20kW separate solar PV systems. The Farm consists of 700ha, of which 458ha is used for production and a further 26ha irrigated, flood Irrigation is used to grow both cotton and sorghum.

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The four meters on site have 274,418kWh of energy consumed costing $58,373 per annum resulting in emissions of 252 tCO2-e. 

To reduce energy consumption and costs onsite the audit recommended: 

  • Install two new 22kW efficient pumps.  
  • Four 20kw solar systems at the different pump sites.

The potential total energy savings determined from thaudit were 105,373kWh, with costs savings of $29,131 and a reduction of 96.9 tCO2e. The total capital expenditure required for these savings is $119,620 with a payback period of 4.7 years. 

 

Table 1. Recommendations and Savings from the Energy Audit. 

Recommendation  Cost to Implement ($)  Energy savings (kWh)  Cost Savings ($)  Payback Period (Years)  Emission Savings (tCO2-e) 
Replace pump one 22kW  15,890 40,316  8,576  3.9  36.2
Replace pump two 22kW  15,890 25,275  5,376  3.0  23.2 
Four 20kW Solar PV 87,840 39,782  15,087  5.8  36.4 
Total  119,620 105,373  29,131  4.2  95.8

It is recommended to replace the top bore pump with a pump matched to the task requirements. Before replacing the pump there are four duty points to consider each with different friction losses, due to the irrigation design. With the replacement, pumping hours would be reduced by 35% and pump energy consumption by 50.2%. The second bore requires the same considerations due to the different friction losses, this replacement should reduce the pumping hours by 8% and the pump energy consumption by 35.9%. The payback period for the pumps is 1.9 and 3 years, respectively, with a reduction of 65,591kWh and costs of $13,952.

Collectively, by installing four 20kW solar systems at the separate NMIS consumption could be reduced by 39,782kWh and costs by $15,087.

Following the audit recommendations, the grower decided to replace the pump one. Post implementation savings and metrics have been calculated from the Measurement and Verification process, with achieved energy savings of 10% and cost savings of 12%, as follows.

Table 2. Actual savings from Implemented solution. 

Recommendation  Cost to Implement ($)  Energy savings (kWh)  Cost Savings ($)  Payback Period (Years)  Emission Savings (tCO2-e) 
Replacement of pump one 22kW  28,117 26,724 7,182  3.9  21.6

 

Table 3. Pre and Post Implementation Metrics. 

Metric  Pre-Implementation  Post-Implementation  Reduction % 
Energy Consumption (kWh)  274,418  247,694 10
Energy Costs ($)  58,373  51,191  12
Emissions (tCO2e)  252  230.4  9

 

An energy audit is a good investment 

An energy audit is a great first step in moving a business towards a more efficient future by reducing energy use, costs, and Carbon emissions onsite.  

An energy auditor will review your past energy bills, your equipment, and the way your business operates. They will show you where you are using excess energy and explain what you can do about it.  Find out about what’s involved in an energy audit HERE. 

See our range of agricultural energy efficiency case studies HERE and Subscribe to our bi-monthly energy e-news HERE  

If you have any energy efficiency related questions for the team get in touch at energysavers@qff.org.au. 

The Energy Savers Plus Extension Program is delivered in by the Queensland Farmers Federation with support and funding from the Queensland Department of Energy and Public Works.  

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