Whole Health: Sustainability's Back End

Supermarkets enjoy offering reusable bags, installing solar panels and other marketable sustainability initiatives. But if they're truly going to make an impact, retailers may need to get down and dirty. Wal-Mart and Tesco, two of the largest, most influential retailers on either side of the Atlantic, have been doing just that with new projects aimed at curbing emissions of a different kind cow gas.

Supermarkets enjoy offering reusable bags, installing solar panels and other marketable sustainability initiatives. But if they're truly going to make an impact, retailers may need to get down and dirty. Wal-Mart and Tesco, two of the largest, most influential retailers on either side of the Atlantic, have been doing just that with new projects aimed at curbing emissions of a different kind β€” cow gas.

At Wal-Mart's sustainability conference in Bentonville, Ark., this summer, the company presented a video about new methane digesters it installed at the dairy farms that process its Great Value brand of sour cream. The machines limit air pollution, converting the cow waste into enough electricity to power each of the farms.

Across the Atlantic, Tesco's project seeks to backtrack even further down the food chain. Scientists at the British retailer's Dairy Centre of Excellence in Liverpool are attaching small, specialized microphones to the bovines to listen in on their stomachs. What they hear indicates how much methane is being produced. Tesco officials hope that will allow researchers to determine which feeds have the lowest impact on gas production.

β€œIt's vital that we help farmers get methane emissions down,” David North, Tesco's community and government director, told London's Daily Telegraph.

According to a United Nations report, venting livestock is responsible for 18% of the world's greenhouse gas emissions.