Energy Efficient Commercial Refrigeration

An energy efficient commercial fridge is better than a cheap commercial refrigerator. There are two main reasons for this. The first is the cost savings that are involved with lower energy consumption. The other is the smaller impact on the environment and our world at large. A more eco-friendly fridge is designed to minimise energy consumption, and, as such, it minimised unnecessary wastage.

Variable Speed Drive

Savings Calculator

Maintenance & Replacement

Potential Savings Table

Old Units vs New Units

Optimisation Tips

Variable Speed Drive

Put simply, a variable speed drive (VSD) makes sure that the energy used in the commercial refrigeration system is matched to the refrigerator’s load. Rather than running at full capacity all the time, a system with a VSD will only use the required energy, greatly reducing running costs and boosting efficiency. This applies to stainless steel refrigeration, glass display refrigerators, storefront fridges, and more.

If the refrigeration system is running at or close to full capacity for most of the time then a VSD will not improve energy efficiency. However, for a system that runs at least 2000 hours per year and has variable load requirements, a VSD is the preferred option in terms of energy efficiency1.

Maintenance & Replacement

Keeping a piece of machinery in good repair is a sure-fire way to reduce any unnecessary running costs, especially for a restaurant, café, or any other commercial kitchen fitout. A machine that has to do more work because of a build-up of contaminants, or running without an appropriate amount of fluid, or because the condenser wasn’t cleaned will run at a higher energy usage than a well maintained counterpart. Making sure your refrigerator is in good working order will extend the lifetime, lower the running cost, and will guard against any unforseen breakdowns or future issues.

However, even a well maintained machine will slowly succumb to the day-to-day effect of continual usage. A refrigeration system that is older than 10-years is typically inefficient, and replacing the system may increase efficiency by up to 30-40%2. Regular monitoring and testing will help avoid letting the efficiency sink this low as well as help identify future problems.

Old Units vs New Units

An old system may have:

  • Worn or poorly insulated coolant pipes allowing the system to gain heat resulting in higher energy consumption and the potential spoilage of products.
  • A growing difference between evaporating and condensing temperatures can reduce energy efficiency. A “1°C reduction in temperature lift can improve plant efficiency by 3–4%”3.
  • A system that has grown any hot-spots will lose effectiveness of the fan and pump motors.

A new system can have:

  • Variable-speed fans can be installed on the compressor and setup to minimise head pressure while using minimal energy rather than running at a continual speed. Reduced head pressure lowers energy consumption4.
  • Rather than a VSD, the cooling load can be efficiently split up between smaller compressors that are configured in a way that minimises energy usage when running on a partial-load operation.
  • Monitoring gauges can be installed to easily identify problems and help in maintaining the system.

Fridge Monitoring System

  • Easy To Use
  • Reduced Cost
  • Energy Saving
  • Centralised System

Potential Savings Table

Method Potential Energy Savings
Use of electronic expansion valves 20%
VSD on motors 20%
VSD on evaporator and condenser fans 2–3% of total refrigeration costs
Evaporator pressure regulators 2.5% greater compressor capacity for each degree of saturated suction temperature
Evaporator pressure regulators 2% for each degree increase in saturated suction temperature
Reduced temperature lift 3–4% improvement for 1°C reduction
Conversion from liquid injection oil cooling to external oil coolers Over 3%
Refrigeration system replacement if older than 10 years Up to 30–40%
Refrigerant selection 3–10%

Savings are not necessarily cumulative. Information sourced from Sustainability Victoria5.

Optimisation Tips

  • Inspect your coolant pipe insulation for moisture; a formation of ice can damage the insulation and reduce efficiency of the system.
  • Check you’re using the most appropriate coolant for your specific commercial kitchen fitout.
  • Look for any spots in your system that may be affected by the environment. Outside sources of heat means more work for the commercial refrigerator system.
  • Use the exhausted heat from the system for pre-heating water pipes and other uses. Rather than wasting the unwanted heat from the refrigeration system, it can be repurposed to improve the whole kitchen efficiency.
  • Check your seals are intact and aren’t leaking in any heat from outside of the refrigerator.
  • Make sure the unit hasn’t been knocked around and has been bumped out of level. Keeping the fridge properly upright makes sure all the seals are properly aligned and working correctly.
  • Assure that your fridge unit has appropriate room for external ventilation. A building up of heat will reduce the fridge’s effectiveness.
  • Clean your condenser weekly!