British retailer Marks and Spencer is expected to open its most carbon-efficient store at Stratford City, close to the 2012 Olympic Park in September. Within the scope of the company’s refrigerant policy striving for more environmentally friendly solutions, the up-coming store will be already the fourth to use a system based on hydrocarbon-CO2 refrigeration technology.

The third largest M&S store of 136,000 sq ft (about 12,634 m2) will use hydrocarbon R290 propane in its refrigeration system. This step comes in accordance with the long-term strategy of the famous retailer, which aims to completely eliminate HFC refrigeration systems from its stores by 2030.

Refrigeration system generates 200kW cooling capacity

The technology designed by Oaksmere Refrigeration and manufactured by GEA Searle utilizes pumped volatile CO2 as the distributed fluid. With the overall cooling capacity of 200kW the system is composed of:

• 2 central packages using R290 low-pressure receiver systems configured in 4 independent circuits
• 2 CO2 circuits providing cooling to the sales floor display cases and back stage rooms

While the fluid at -3 ˚C directly cools the high temperature cases, the low temperature cases are cooled by a sub-critical CO2 system evaporating at -35 ˚C. At the same time, the retailer has put to test a limited number of integral display cases using the hydrocarbon R290 each with system charge of 1.04kg split into 2 independent circuits of 520g.

Safety measures in place

In addition to the compliance with the DSEAR requirements fire accreditation companies, fire authorities and the company’s own Fire and Safety Department has been involved during the development process to assess possible risks and provide safety analysis for the equipment used. In order to ensure safety the personnel dealing with the maintenance and service of the system has been given an appropriate training.

‘Sustainable learning’ stores

Marks and Spencer intends to become the world’s most sustainable retailer by 2015 and aims to create stores that will incorporate sustainable and innovative construction features which means creating stores that:

• Have zero embodied carbon in construction;
• Are made from 100% recycled material;
• Are 100% recyclable when refurbished or no longer needed;
• Have a net positive biodiversity impact;
• Are resilient to climate change.

First of the ‘sustainable learning’ retail outlets opened its door to the public in Sheffield in April 2011.