Freezers produce 25% of supermarkets' carbon footprint
Supermarket fridges and freezers are environmentally unfriendly, spewing out bad gases that make up more than a quarter of the companies' total carbon footprint.
The HFCs (hydrochlorofluorocarbons) can have as much as 4000 times more impact on global warming than carbon dioxide, say green campaigners.
None of the 10 high-street stores fared well in a survey that had Iceland scoring an alarming -1 out of a hundred, closely followed by rivals Lidl (0 points) and Aldi (+1).
The chains all refused to provide information about what they were doing, and Iceland was given a minus mark for going back on a 1999 commitment to address the issue.
Points were awarded or deducted for refrigeration in-store, behind the scenes and for transport, as well as for leakages, energy-efficiency, training of refrigeration engineers and future plans.
Somerfield was also awarded nothing for failing to participate.
Waitrose scored worst among the major players, with just 12 points putting them seventh in the list.
Their responses were "vague and uninformative giving the impression they were apathetic and didn't take the issue seriously".
The Chilling Facts report, the first of its kind, said Morrisons (17) also seemed to be lagging "because they refused to participate in the survey".
Campaign co-ordinator Fionnuala Walravens, of the Environmental Investigation Agency, said: "The HFCs make up a quarter or more of a supermarket's total carbon footprint, in some cases up to 30%. And this is before you take the energy they use into account.