How smart industry collaboration between system manufacturers and the European grocery chain led to the production of an energy efficient propane plug-in cabinet now set to be customised for the North American market.
Typically, energy costs are high in Germany and most other European countries, whereas sales margins in the food retail sector are traditionally low.
According to studies, refrigeration in standard grocery stores accounts for approximately 55% of a store’s primary energy, so installing a high-efficiency refrigeration system can drastically reduce energy bills for discount retail stores.
As a response to this situation, a system manufacturing company was approached by market-leading grocery chains to supply a self-contained display cabinet that possesses higher efficiency than existing cabinets, to help improve margins.
The system manufacturer teamed up with secop – Danfoss compressors at the time – as one of their main compressor suppliers to work on a cabinet according to the specifications outlined by the grocery chains. The product was a huge success and is now being adapted for North American markets.
In shecco’s recently launched GUIDE to Natural Refrigerants in North America 2015, secop outlines how it brought the self-contained cabinet to market. Click here to read more
Space saving solution set to meet NA demand
Self-contained display cabinets are very common among European discount food retailers because confined floor spaces do not favour large centralised installations.
Secop’s single plug-in cabinets can be quickly rearranged if standing alone or installed in an island setup to be accessed by the customers from both sides. They usually contain frozen and low-temperature chilled food, rather than dairy products. As well as improved energy efficiency, the cabinets also required additional functions for their daily operation, including:
Hazard analysis and critical control point
Alarm to signal failures at set temperatures
Remote monitoring of temperatures and consumption levels
Automatic defrost to prevent accumulation of ice that increases energy consumption due to insulation effects
To reduce energy consumption of the refrigeration cycle, secop proposed to use an electronically controlled compressor that is able to adjust its rotating speed, and therefore the cooling capacity, to cater for the North American market (i.e. for 115 Volt 50/60Hz).
secop’s experiences with variable speed compressors have shown its potential to reduce energy consumption by up to 40% compared to a conventional compressor with a synchronous motor and fixed speed/cooling capacity running on/off.
The demand will come from strengthened policy that requires compliance with stricter energy regulations. secop’s integrated controller for food retail cabinets is under development and will be released in 2015. The controller can be modified for compatibility with all other cabinet types where the energy efficiency is a major buying criterion.
Thirty percent energy savings compared to fixed speed compressors
Intensive tests in labs and in the field have shown solid savings in energy consumption compared to variable speed compressors using HFC R404A. The test results reveal it used 30% less energy compared to the identical system using a fixed speed (on/off) compressor. With the substitution of R290 (propane) as the refrigerant, the cabinet’s energy efficiency was improved by a further 9%.
Additional savings come from secondary effects, which include the scheduled (hot gas) defrosting of the cabinet and the full integration of application functions into one controller, such as fan and illumination control.
By adapting new compressor technology to a conventional application and tailoring a solution for plug-in cabinets in discount retail stores, significant savings in total cost of ownership can be achieved. It’s no surprise the system manufacturer now has approximately 600,000 units on the market today.