A recent energy audit showed how improving the current systems can lead to energy and cost savings. The recommendation implemented is installing a 39kW solar system at the main 22kW pump with potential energy savings of 41% and emission reductions around 31 tCO2-e per year. Savings will be updated when the measurement and verification process is complete.
Energy Savers
Summary
The farm, near Mareeba, produces limes and papayas and is irrigated year-round depending on rainfall. Water is supplied from the nearby creek.
It is a large site consuming 93,000kWh per year costing $34,000 over different meters and harvests approximately 365ton of produce.
The farm has already invested in energy efficiency with the installation of a large solar system, a new irrigation pump with Variable Speed Drive, LED lighting and VSDs on the packing equipment.
The infrastructure contributing to the energy consumption onsite consists of:
- A large packing shed with packing equipment installed with VSDs and LED lighting
- A small cold room
- A 39kW solar system on the packing shed/house NMI
- A 22kW irrigation pump at the creek
- A house where the grower and family live
A recent energy audit showed how improving the current systems can lead to energy and cost savings. The energy audit recommended the following changes to improve efficiency and reduce costs:
- Tariff Analysis, that considering the solar on the packing shed and the proposed solar on the pump, found a little benefit from changing Tariff 62 to 20.
- Installation of a 39kW solar system at the main 22kW pump. Changing the irrigation schedule to match the solar output will allow for higher utilisation of the electricity generated.
Table 1. Energy and cost savings from audit recommendation
| Recommendation | Annual Energy Savings (kWh) | Annual Cost Savings ($) | Emission Savings (tCO2-e) | Capital Cost ($) | Payback Period (years) |
| Solar system | 38,500 | 9,600 | 31 | 59,700 | 6.2 |
The grower proceeded with the installation of the solar system, with potential energy consumption savings of 41%, costs savings of 28%, and carbon emission savings of 31 tCO2-e per year. Actual savings will be updated once the measurement and verification process is complete.
Table 2. Pre and post audit energy consumption, costs, and energy productivity savings
| Metric | Pre-Audit | Post-Audit | Reduction (%) |
| Energy Consumption (kWh) | 93,000 | 54,500 | 41 |
| Cost ($) | 34,000 | 24,400 | 28 |
| Energy Productivity (kWh/tonne) | 255 | 150 | 41 |
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 on site.
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 energysavers@qff.org.au.
The Energy Savers Plus Extension Program is delivered by the Queensland Farmers Federation with support and funding from the Queensland Department of Energy and Public Works.
