Retail refrigeration

The cost of refrigeration energy has been estimated at some 500 million per year and in the food, drink, supermarket and cold storage sectors this will account for a significant proportion of the site energy costs (ctg046_refrigeration_systems).

This Carbon Trust report dated July 2011 estimated that refrigerated display cabinets use a minimum of 5,800GWh per year. As a GWh is 1 million KWh then the cost of this energy at current values will exceed £754m per annum and is a significant drain on the UK resources.

There are a number of ways in which this energy can be reduced but the most effective is regular cleaning and maintenance which (according to the Carbon Trust) would save up to 10% of the consumed energy.

In the paper “ENERGY CONSUMPTION AND CONSERVATION IN FOOD RETAILING” published by the Brunel University the author states “The energy consumption of supermarkets will depend on business practices, store format, product mix, shopping activity and the equipment used for in-store food preparation, preservation and display. The electrical energy consumption can vary widely from around 700 kWh/m² sales area in hypermarkets to over 2000 kWh/m² sales area in convenience stores. The refrigeration systems account for between 30% and 60% of the electricity used”.

Based upon a unit cost of 0.10 per kWh and taking 30% as the total cost of the refrigeration system then each m² will cost 21.00 per hour. The enormous amount of electricity required for supermarkets to run refrigeration units makes up around 40-70% of their total energy expenditure, depending on store size. It is also estimated that there are approximately 0.8 million refrigerated display cabinets in the UK.

Additionally a typical condenser will cost between £100 and 500.00 to clean and this essential task must be completed to maintain compressor efficiency and reduce failures. 

Clogged condenser coil. Only 1mm of dirt will cause a 21% drop in efficiency.

In the Carbon Trust report the following message is regularly highlighted:

Good practice inspections and maintenance saves energy and money

• Look out for debris/dirt build-up on the Condenser.
• Regularly clean condensers and evaporators.
• Cleaning a blocked condenser will improve compressor efficiency.
• Find out where your condensers are, and check them out.
• If they’re dirty or blocked with debris, they’re costing you money.
• Make sure the cleaning process doesn’t just push the dirt deeper between the fins.

And now there is a simple way to maintain clean condensers which does not involve a specialist technician and keeps the dirt from the fins.

An air intake filter screen is designed to maintain airflow (resistance 1.25pa @ 0.50m/s) whilst filtering out the dirt and debris that is drawn into a refrigerated cabinet enclosure.

This means that you can easily see any dirt build up and quickly remove it by washing or vacuuming.

The patented Permatron PreVent® screen is supplied with a magnetic frame so that they can be easily simply removed when cleaning is required. For the Starbucks case history please check out the RAB website www.rabse.com.

Air intake screens are simple, innovative and hugely effective as they cut down the cost of maintenance whilst keeping coils free of debris.

If you could save 10% of your energy bill by spending a little would you give it a try?