Walmart Stores plans to eliminate 20 million metric tons of greenhouse gas emissions from its global supply chain by the end of 2015.
This represents one and a half times the company's estimated global carbon footprint growth over the next five years and is the equivalent of taking more than 3.8 million cars off the road for a year.

"Energy efficiency and carbon reduction are central issues in the world today," said Mike Duke, Walmart president and CEO. "We've been working to make a difference in these areas, both in our own footprint and our supply chain. We know that we have an opportunity to do more and the capacity to do more."

Walmart came up with the approach of looking at its entire supply chain with the help of Environmental Defense Fund as well as PricewaterhouseCoopers, ClearCarbon Inc., the Carbon Disclosure Project and the Applied Sustainability Center (ASC) at the University of Arkansas. This team will identify projects, quantify reductions, engage suppliers and ensure proper procedures are followed for each GHG reduction claim.

"Reducing carbon in the life cycle of our products will often mean reducing energy use," Duke said. "That will mean greater efficiency and, with the rising cost of energy, lower costs, making our business stronger and more competitive. And, as we help our suppliers reduce their energy use, costs and carbon footprint, we'll be helping our customers do the same thing."

As part of the approach, Walmart will focus on the product categories with the highest embedded carbon, which are defined as the amount of life cycle GHG emissions per unit multiplied by the amount the company sells. Next, the company's goal will be executed by reducing GHGs from a product in either the sourcing of raw materials, manufacturing, transportation, customer use or end-of-life disposal. Lastly, suppliers and Walmart will account for the reductions, ClearCarbon will perform a quality assurance review of those claims, and PricewaterhouseCoopers will assess under consulting standards whether the defined procedures were followed consistently.