The farm irrigates a 70ha and 20ha paddock with a 9–span full circle centre pivot, and a 6-span half pivot, plus drip irrigation. The three pumps totalling 187kW are centrally metered and used in different combinations to operate the pivots. The farm currently pumps 378ML of water per annum, with energy consumption of 85,929 kWh, emissions of 79 tCO2–e, at a cost of $20,454p.a. The drip can be operated without pumping due to sufficient scheme pressure. A solar system has recently been installed onto the roof of the sheds adjacent to the pumping shed.
Recommendations explored in the audit to reduce energy consumption and costs onsite included;
- Duplicate the existing pipeline with 500m of 200mm PVC.
- Install SMS remote start system.
- Automation of the irrigation system.
Table 1. Recommendations and Savings from the Energy Audit
||Cost to Implement ($)
||Energy savings (kWh)
||Cost Savings ($)
||Payback Period (Years)
||Emission Savings (tCO2-e)
|Upgrade Mainline Pipe
|Install SMS remote start system
Installation of a new, parallel 500m of 200mm PVC mainline would reduce friction head and therefore energy consumption by approximately 14%, generate an annual saving of $3,410 with a payback period of 4.5 years. Coupling the mainline upgrade with installation of a SMS remote start system and an automation system would provide an additional benefit, creating a total annual cost saving of $18,859, with a payback period of 3.2 years, and a total capital cost of $50,016.
The automation will enable the farmer to easily manage any tariff with peak/off-peak periods such as Tariff 22A or 24, or load controlled supply, such as Tariff 33. For many farmers, these tariffs are generally considered to be time consuming with manual operation of pumps. Automation can reduce the pumping energy by turning off individual irrigation events ‘at the right time’ with the use of a programmed irrigation duration with/without water detection sensors.
A Sugar Research Australia (SRA) project view HERE, measured reductions of between 10-20% less water used with automation and smart sensors; this would translate to a direct saving if the water were pumped. Additional benefits may include a reduction in labour, fuel, vehicle repairs and maintenance.
The additional benefits attached to the SMS remote starting and automation would see costs reduced significantly due to a slight increase in tonnes of cane produced per annum. Including the potential production benefit of roughly 5t/ha at $30ha ($10,514 for a 70ha paddock) costs could be reduced by 92%, if all the audit recommendations are adopted (Table 2).
Table 2. Pre and Post Audit Metrics
|| Reduction (%)
|Energy Consumption (kWh)
|Energy Costs ($)
Energy Audits for your Business
An energy audit is a great way for a business to cut costs and boost productivity.
An energy auditor will review your past energy bills, your equipment and the way your business operates. They’ll show you where you’re 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 email@example.com.
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.