Over a third of Marks & Spencer (M&S) products sold, amounting to over a billion items a year, now boast some form of sustainability credential.
Interim results for the retailer's pioneering Plan A sustainability strategy show 35 percent of its products have an eco or ethical feature that goes beyond the market norm.
Adam Elman, head of Plan A delivery at M&S, said the company was confident it would reach its targets of embedding sustainability features into half of its products by 2015 and its entire range by the end of the decade, but he also acknowledged there was still "work to do."
"It's something we still have to work really hard at," he told BusinessGreen. "We don't want to stop at one attribute, we want products to have multiple attributes."
Referencing product lines including the "world's most sustainable" suit, coat, bra and chinos, Elman added: "We don't want to do a few one-offs, but get the learnings [from these lines] into every single product."
Plan A racked up savings of $166 million for M&S last year and while Elman declined to discuss figures, he said the company is still looking for new areas of opportunity for its Plan A push, which could include investment in renewable energy.
"Renewable energy is important from an environmental point of view, but also there's a good business case," he said. "We're looking at wind, [solar] PV, solar thermal ... and we have biomass at Cheshire Oaks, which provides 70 percent of the store's heating."
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