Sainsbury’s is trialing what it claims is the world’s first naturally refrigerated trailer in a move which could help cut its carbon footprint.

The supermarket giant has joined forces with a natural refrigeration technology specialist for a two-year trial of its new system, which uses carbon dioxide for cooling instead of the more harmful hydroflourocarbons (HFCs) typically used. While both are greenhouse gases, HFCs are usually many times more powerful.

Sainbury’s said if the technology proves successful it plans to roll the system out across its whole fleet over the course of seven years. During that period the supermarket claims the new system would have the same impact as removing 70,000 tonnes of CO2 from the atmosphere.

The trial is part of a wider move by Sainsbury’s to phase out HFC refrigerants across the business. In 2011 it converted all its depots to CO2 refrigeration and by 2030 it plans to do the same in all its stores. The company has already checked 160 stores of the list and is hoping to reach 250 by 2014.

Nick Davies, Sainsbury’s Head of Transport Operations said: “The new carbon dioxide technology has much less of an impact on climate change and we hope it will play a big part in helping us reduce our carbon emissions.”

The supermarket has set a goal of reducing its depot to store transport CO2 emissions by 35% by 2020 and over the summer announced it had reached its zero waste landfill target.