Brisbane based Asian fish importer and retailer, Aus Asia Foods, has improved its refrigeration capacity and saved thousands of dollars a year in energy costs by implementing Variable Speed Drives (VSDs).
VSDs have proven to be a great solution to improve energy efficiency and temperature control.
The project utilized Schneider Electric VSDs, a Keep It Cool Refrigeration installation, and Koldpak’s OEM capabilities.
Importing a wide range of fish products into Australia, as well as sourcing products locally, Aus Asia Foods relies on its refrigeration capacity to keep the products food safe and compliant.
When the company required two new, large freezers, Keep It Cool Refrigeration installed the new units, with parts and expertise supplied by Koldpak.
Aus Asia Foods was also seeking to lower the energy costs of its new freezers and increase the longevity of their machinery.
Working with Koldpak, Aus Asia Foods agreed to the addition of a variable speed drive (VSD) solution on the 7.5kW compressor for one of their freezer rooms.
One unit was selected initially to quantify savings. If the solution was successful Aus Asia Foods would expand the project.
In a normal refrigeration compressor set up, the compressor is either on all the time, or completely off. This means that the compressor needs to ramp up quickly and powerfully whenever the temperature in the refrigeration unit gets too high.
A VSD solution adds smart control to the compressor, allowing it to operate at the exact speed needed to ensure temperatures are kept optimal. This means less energy is needed overall to achieve the same outcome.
With the two same-sized freezer rooms located alongside each other, Koldpak and Schneider Electric worked together to set up the study, running the VSD solution on just one of the 7.5kW compressor freezer rooms.
The other freezer used a standard direct on line (DOL) setup. Care was taken to ensure both rooms were loaded with similar stock levels and were used in a similar fashion.
A Schneider Electric Altivar ATV630 Process Drive was chosen for the project. The drive has extensive graphic dashboards, including an energy consumption monitoring dashboard, to see the results.
The drives also have an integrated power measurement function, which is accurate to within five per cent.
Being able to monitor and analyse input power, energy produced and the KPIs directly from the process management system meant Aus Asia Foods did not have the hassle of needing a separate piece of software or device to check their usage.
Running the two refrigeration units alongside each other, one with the drive and the other without, clearly demonstrated the energy savings made as a direct result of the variable speed drive.
After one month, 1316kwH energy savings had been made as a result of using the drive. At a conservative cost estimate of $0.11 kWh this amounts to monthly savings of close to $150. With such strong evidence, Aus Asia Foods decided to add an Altivar Process Drive to the second unit and saving from the second unit over a period of six months were 5216kWh, almost $900.
Aus Asia Foods manager, Jacky Mo, said the VSDs are saving between $100 and $125 on each unit, per month.
With the two units running, he said the conservative estimated savings each year are around $3,000.
As the estimated cost of $/kWh 0.11 cents is very low, the real-life savings could be twice that amount, producing energy cost savings of as much as $6,000 a year.