At last week’s conference, delegates from major supermarkets discussed the challenges they faced going green

“Supermarkets are leading the way in sustainability.” That, at least, is the view of Steve Fuller, head of construction delivery at Marks & Spencer, who was speaking at the Supermarkets Conference last Friday.

Thankfully the conference delegates didn’t let the man from Marks get away with mere platitudes. He and his counterpart from Tesco – Martin Young, the retail giant’s chief architect – were pressed to set out their green credentials.

Here are five points that came out of the discussion:

1) The numbers just don’t stack up for installing on-site renewables such as solar PV or wind turbines at every store – according to Fuller. This admission led to a broader discussion of the role of technology in solving the supermarkets’ sustainability problems. Unsurprisingly it comes down to strict cost-benefit analysis. Fuller said M&S was now committed to rolling out LED lighting to all its food stores – but that it had taken four years for LED lighting to come down in price enough to make this viable.

2) The retailers are rolling out sustainable stores with earnest. Fuller in particular held up the recently opened eco-store in Sheffield as a sign of things to come. The store on Ecclesall Road recycles heat given off by the stores’ refrigeration facilities while rainwater is recycled for the toilets. Fuller added that 75% of the eco-measures used in the trial had been incorporated into their specifications for new stores in the year ahead.

3) But both retailers admitted the bigger challenge was making their existing estates more sustainable. One thing customers can expect is refrigerators with doors in future – currently around a third of the retailers’ energy is consumed by refrigerators, they said.

4) The impetus to go green is coming from the top. Stuart Rose of M&S is known for his commitment to the green agenda, but Tesco’s new chief executive Philip Clarke is also determined to make a concerted green push. In its CSR strategy launched last week Clarke said the environment would be a “major focus” of his leadership. Moreover, Tesco joined the ranks of organisations setting radical, if distant, carbon reduction targets – the retailer wants to be zero carbon by 2050.

5) Both supermarkets acknowledged the need to get construction firms on board earlier in the development process if they are to meet their challenging sustainability targets. Young said Tesco would use a “learn and benchmark” approach to roll-out the most effective sustainable measures across its estate.