Hailing the new technology for having a much lower impact on climate change, Sainsbury’s head of transport operations Nick Davies hopes it will play a big part in helping the company reduce its carbon emissions.

“We will be monitoring its performance closely and if successful, in line with our replacement plan, it could help us save over 70,000 tonnes of CO2 compared to the current refrigerated trailer fleet,” added Davies.

The CO2 refrigerated unit trial, which uses CO2 instead of HFCs as a refrigerant, is part of the retailer’s review of its transport refrigeration gas and work to reduce its carbon footprint, which includes converting its stores to natural refrigeration by 2030.

The natural refrigerant CO2, also known as R-744, is non-ozone depleting, while its Global Warming Potential (GWP) of ‘one’ compares very favourably to conventional refrigerants R-134a and R-404A, which have GWPs of 1,300 and 3,260, respectively.

The GWP of CO2 is also lower than other natural refrigerants, such as propane and ammonia, so even in the event of a leak the use of CO2 adds no new environmental risk.

Sainsbury’s was the first UK retailer to commit voluntarily to phasing out harmful HFC refrigerants.

It converted its refrigerated depots in 2011 and is on track to switch 250 stores to CO2 refrigerant by 2014 with more than 160 stores already moved to the natural refrigeration system.

Currently all new stores are fitted with CO2 as standard and its Haslucks Green Local store in Solihull is also trialling the very first small-scale CO2 refrigeration system, making it, Sainsbury’s claims, Britain’s greenest convenience store.

Reducing the company’s CO2 emissions from its transport operations further, Sainsbury’s has recently extended its Dual-Fuel fleet to 51 vehicles saving up to 25% in carbon emissions, more than 2,090 tonnes of CO2.

The environmentally friendly fleet, now one of the largest in the UK, operates on a combination of diesel and bio-methane, produced from rotting organic material in landfill. Each Dual-Fuel vehicle will save around 41 tonnes of CO2 from being dispersed into the atmosphere each year.

Sainsbury’s aims to reduce its depot to store transport CO2 emissions by 35% by 2020 and achieve an absolute reduction of 50% by 2030, against a 2005 baseline.

Leigh Stringer

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