See repost from Inside Retailing...
Walmart, the world's largest retailer, says it wants its suppliers to reduce 20 million metric tons of greenhouse gas emissions by the end of 2015.
The discounter's push to eliminate what it says is the equivalent of 3.8 million cars off the road for a year goes beyond its efforts to date to reduce its own emissions by designing more energy-efficient stores and other measures.
Walmart is collaborating with the Environmental Defense Fund and other environmental experts to measure reduction. It said it won't force suppliers to make changes but will work with them on projects that will reduce both emissions and costs.
See more.. http://www.insideretailing.com.au/Latest/tabid/53/ID/7669/Walmarts-green-push.aspx