The irrigation energy audit assessed a number of irrigation systems, and recommended the addition of variable speed drives to an existing pumping station consisting of 2 x 7kW and 1 x 5.5kW fixed pumps. The upgrade would result in energy savings of 1% on total energy consumption, corresponding to 15% savings of energy use for irrigation, with a payback of 11 years and with carbon emission reductions of 1.4 t CO2-e per annum.
The nursery, near Gatton, has 17 hectares dedicated to intensive plant production and specialises in seedlings, natives and shrubs, providing plants in pots, hanging baskets and punnets.
Irrigation is automatically controlled accordingly to the various stages of growth in different areas of the site. In addition to the irrigation system, the nursery also uses compressors, robotic transplanters, denesting lines, tray fillers, a potting machine and a soil blender in its operations.
The nursery is trialing new water-efficient sprinklers which will significantly reduce water consumption. A decision to upgrade the fixed speed pumps with possibly smaller motors will depend on the outcome of the trial. The owner may find that pumping requirements can be managed by the remaining pumps as a result of water savings achieved.