Refrigeration – commercial-scale

Large-scale refrigeration, chillers and cool rooms are used in many industries, especially those dealing with meat and dairy products, food processing, and for process cooling in the chemical industry. The cost of running refrigeration far exceeds the cost of the equipment. In the food production and food retailing businesses, refrigeration can account for 50% of energy costs.

Energy efficiency measures include:

• Purchasing new compression refrigeration equipment; those with highest energy-saving specifications use around 30% less energy.
• Using sorption chillers, both ABsorption and ADsorption, which use a thermal compressor instead of a mechanical compressor. These can offer an efficient solution if a source of waste heat available and they can also be powered by solar thermal technology.
• Correct system sizing – refrigerators and chillers are often oversized.
• Adequate insulation and sealing of refrigerated rooms to keep heat out and minimise cooling requirements.
• Setting refrigerators at the highest permissible temperatures.
• Regular servicing and maintenance, including:
  • Cleaning condensers and evaporators.
  • Regular defrosting.
  • Detecting and repairing leaks.
  • Inspection and repair of pipe insulation.
• Using monitoring systems that check for changes in pressure and temperature.
• Recovering heat where possible to use to heat water or for process heat.
• Using passive cooling systems that can reduce or replace the energy demand for cooling.

A large range of technologies are currently available, especially for large-scale requirements, which can significantly reduce costs. These include cooling towers, hybrid coolers and free coolers. When planning new projects, their potential should be investigated and expert advice sought.

Overviews of cooling technologies currently available. Those driven by heat can be powered by solar thermal systems. However, many are only suitable for large-scale applications.