Sainsbury's will switch to CO2 to save CO2

UK retailer Sainsbury's has announced a seemingly counterintuitive strategy to cut the amount of CO2 emitted from its refrigerators - by switching them to use CO2.

In a speech made today to the Environment Agency conference, the retailer's chief executive Justin King explained how Sainsbury's plans to reduce its carbon footprint by around a third by changing fridges that currently run on HFCs and HCFCs – so-called "F-gases" - to run devices that use carbon dioxide instead.

The strategy makes sense according to Sainsbury's, as the new fridges are more energy efficient, which cuts down on the carbon emissions that result from the electricity required to run them.

Although Sainsbury's is talking in terms of cutting its carbon emissions - it may be more accurate to see the strategy in terms of a cut in total greenhouse gases.

The new fridges will emit some CO2 but it will be less harmful overall than the damage caused by the emission of the F-gases, which have a Global Warming Potential (GWP) of 2,000 to 3,000 times that of a similar quantity of CO2, said Sainsbury's.

"Fridges are by far the biggest source of CO2 emissions in any supermarket through both the energy required to power them and the refrigerants themselves. If all supermarkets in the UK switched to this sort of refrigeration, the reduction in CO2 emissions would amount to around 2m tonnes a year," King said.

The retailer plans to switch to CO2 in all of its stores by 2030, with the first 135 stores set to be converted by 2014.

Commenting on the move, Dr Doug Parr, chief scientist with Greenpeace UK, said that while F-gases are a lesser-known cause of climate change, they are still a significant contributor.

"Sainsbury's announcement of a timetabled phase-out of these dangerous chemicals is a signal that their removal is economically feasible as well as environmentally necessary," he said.

"The leadership the company is showing on F-gases stands in stark contrast to our political leaders' timid reluctance to be the first mover on anything - they must learn from this."

As well as detailing its fridge strategy, King will also go on to bemoan the lack of green engineering talent available in the UK.

"A serious barrier preventing other companies from following our lead is a lack of skilled engineers to build and maintain these units. We are doing our bit - this initiative will lead to 200 green jobs in the UK through the re-training and hiring of specialist engineers - but business alone can't ensure a sufficient supply of people with the right skills and training," he will say.

According to King, the government needs to up the UK's investment in environmentally sustainable skills.

"Government needs to seize the opportunity here by helping people re-train to work in the rapidly expanding green sector. We'd like to be in a place where we can use more home-grown expertise to reduce UK carbon emissions in line with future targets, instead of looking to other countries for knowledge and innovation," he said.

Sainsbury's is not the first retailer to hit on the potential of CO2 refrigeration to improve energy efficiency.

In January, Tesco announced that its new stores in the UK would be up to 70 per cent more efficient than previous facilities thanks to skylights to let in more daylight, a store-wide energy and water management system for tracking usage patterns, a natural ventilation system that cuts the need for heating and air conditioning, and a natural refrigeration system that relies on CO2 rather than HFCs.

But while Sainsbury's has committed to cut both the use of HFCs and HCFCs, some environmental strategies involve substituting one gas for the other.

In an open letter to the United Nations Environment Programme released in May, Deputy Assistant Secretary of State Daniel Reifsnyder said that the US was committed to reducing emissions of HFCs, which are expected to "increase dramatically" as manufacturers deploy the gas as an alternative to the hydrochlorofluorocarbons (HCFCs) that are blamed for damaging the ozone layer.