The audit recommended optomising the VSD speed to reduce friction losses, balancing efficiency with crop requirements. This no-cost project is saving the farmer nearly $20,000 per annum with a reduction of 19% energy consumption.
This case study shows how a Clare melon farm is reducing energy costs thanks to the energy savings program. The farms has reduced the energy cost for cold rooms and packing shed by 10 – 15% off their annual $250,000 bill. Further savings are being made with irrigation efficiencies.
A range of initiatives were identified including replacing some pumps and motors with new pumps and variable speed drives, with a payback period of 2.8 years and annual cost savings of around $16,500. An extra $10,000 annual saving is potentially available at the site by reviewing the tariffs of the pump stations.
The audit recommended replacing high pressure travelling guns with a low pressure boom irrigator and installing a variable speed drive to maintain 65psi at the booms. The project is expected to save 20% energy and has a payback period of 3 years.
The audit presented 2 options to improve the efficiency of an 18kW pump: upgrading to a high efficiency model, or adding an VSD, both of which would save nearly $4,000 per year and pay back within around 2 years.
The irrigation audit identified energy savings of 10% with a payback of 3.4 years by modifying the discharge piping on the 45kW pump to reduce pressure losses. Additional savings were identified by replacing pumps and adding a variable speed controlled, but with longer payback periods.
The irrigation energy audit identified a number of initiative that would save over $110,000 over 10 years. These included replacing oversized pumps, and adding Variable Speed Drives where the changing elevation of the Centre Pivots caused variable head pressure. The audit also identified $600 in annual savings through tariff review.
The irrigation audit identified a number of opportunities on site including modifiying pipe systems to reduce pressure loss, impellor modifications and installation of variable speed drives. Energy savings of 16% with a payback of 1.3 years were identified. The audit also identified up to $11,000 available by reviewing the tariff pricing structure for the pumps.
The irrigation energy audit assessed the site pumping systems including creek pumping and transfer pumping, and recommended adding variable speed drives to the 55kW pumps driving the Centre Pivots, and reducing head pressure. Energy Savings of 19 – 30% were identified with payback periods between 8.4 – 23.9 years.