The farm, near Mareeba, produces red papayas and coffee. It is irrigated year-round depending on rainfall. Water is supplied from several on-site irrigation dams or directly from an irrigation channel as part of the Tinaroo irrigation scheme.
It is a large site consuming 250,000kWh split over several meters per year and harvests 2,500 T of papaya and 40 T of coffee per year over 115ha.
The infrastructure contributing to the energy consumption onsite consists of:
- A sophisticated nursery complex with hot houses
- Several pump sheds (30kW, 11kW, 2x 15kW)
- 80kW solar system attached to the large pump
- 10kW solar system serving the nursery complex
- Large packing shed (not included in audit)
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, which found that the main pump house would save $4,000 a year by changing from Irrigation Tariff 66 to Small Business Tariff 20.
- Upgrade fluorescent lighting in nursery complex to LED, which can change light spectrums according to the needs of the plant.
- Install a ground-mounted 20kW solar system at the site of one of the 15kW pumps.
Table 1. Energy and cost savings from audit recommendations
Recommendations |
Annual Energy Savings (kWh) |
Annual Cost Savings ($) |
Emission Savings (tCO2-e) |
Capital Cost ($) |
Payback Period (years) |
20kW solar system |
25,000 |
6,500 |
20 |
35,000 |
5.4 |
Lighting upgrade |
5,280 |
2,400 |
4.2 |
15,500 |
6.5 |
Tariff Change |
– |
4,000 |
– |
– |
– |
Total |
30,280 |
12,900 |
24.2 |
50,500 |
6 |
The grower has proceeded with the installation of the solar system and changing the tariffs, with estimated energy savings of 10% and emission reductions of 20 tCO2-e per year.
A real-time energy meter has also been installed on the solar system, allowing monitoring of energy generation. During times of excess solar generation, the site can make decisions to better utilise energy generation or export energy to the grid. The device will also allow the business to understand their energy consumption, being able to find further demand reductions onsite. Read more about HERE.
By installing the recommendations in the audit, the business could reduce energy consumption by 10% and costs by 19%, with carbon emission savings of 20 tCO2-e per year. Actual savings will be updated once the measurement and verification process is complete.
Table 2. Pre and post implementation energy consumption, costs, and energy productivity improvements
Metric |
Pre-Implementation |
Post-Implementation |
Reduction (%) |
Energy Consumption (kWh) |
250,000 |
225,000 |
10 |
Cost ($) |
55,000 |
44,500 |
19 |
Energy Productivity (kWh/tonne) |
100 |
90 |
10 |
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.
