The retailer will build on initiatives like its supply chain scorecard launched in 2007 to work with suppliers to reduce emissions by taking steps related to areas like transportation, raw material sourcing, and waste.
Although Walmart plans to cut 20m metric tons from the supply chain, the company also wants expand, and expansion brings with it greater carbon emissions. But the retailer says there will be a significant net benefit.
According to Walmart estimates, a 20m metric ton emission reduction by 2015 is one and a half times its projected global carbon footprint growth over the next five years.
Three step plan
Working with the Environmental Defense Fund (EDF) and other advisers including PricewaterhouseCoopers and the Carbon Disclosure Project, Walmart has devised a three step plan to reach its supply chain carbon target.
The logic behind the process is to concentrate on the emissions that are easiest to cut out.
The first step is therefore to select the product categories with the highest embedded carbon - defined as the amount of life cycle GHG emissions per unit multiplied by the amount the company sells. Matt Kistler, head of sustainability at Walmart, identified fresh food as one of these big emitting categories along clothing and certain electronics.
Then Walmart moves on to the action phase that involves emission cuts from selected products to be delivered in either the sourcing of raw materials, manufacturing, transportation, customer use or end-of-life disposal. Walmart must demonstrate it had direct influence on the reduction and show how that reduction would not have occurred without its participation.
The final stage of the process involves assessment of the reductions by Walmart and its suppliers before claims are verified by ClearCarbon and PricewaterhouseCoopers.
Sustainable product index
Walmart is already working with suppliers to encourage them to reduce their environmental impact.
Last year, the retailer announced plans for a world-wide sustainable product index that aims to gather the data necessary to give all its products an eco-rating so customers know the green credentials of the products on the shelves.
It has also created a packaging scorecard to put pressure on suppliers in the US to reduce their packaging.