Walmart announces plan to to cut 20 million tons of greenhouse gas emissions in their supply chain over the next five years.

In another large-scale sustainability effort aimed at greening their supply chain, Walmart today announced the lofty goal of cutting 20 million metric tons of greenhouse gas (GHG) emissions from its global supply chain by the end of 2015. The reductions would equal 3.8 million cars-worth of greenhouse gas emissions, or, 1.5 times the company's projected CO2 growth over the next 5 years.

“Energy efficiency and carbon reduction are central issues in the world today,” said Mike Duke, Walmart president and CEO, in a live televised announcement on Thursday. Duke said that Walmart has 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.”

Duke said that working with suppliers, the plan would be measurable and attributable, calling it "a plan that will make a difference."

“Reducing carbon in the life cycle of our products will often mean reducing energy use," added Duke. "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.”

Duke said that reductions can come from any phase of a products lifecycle, including sourcing raw materials, manufacturing, transportation, customer use and end of life disposal.

Fred Krupp of Environmental Defense talks with Walmart's Leslie Dach about Walmart's new greenhouse gas emissions strategy.

“Today the world’s largest company begins a global race for carbon pollution cuts,” said Fred Krupp, president of Environmental Defense Fund. “Walmart’s bold move will help companies identify steps to slash pollution and costs."

"What's sensational is that you're going to launch a race, a treasurehunt," said Krupp, referring to Walmart suppliers finding ways to reduce GHG emissions.

Working with Environmental Defense Fund, Price Waterhouse Coopers, Clear Carbon Consulting and the University of Arkansas, Walmart created a plan of action to find and measure the greatest opportunities for reduction, and a plan to verify those GHG reductions.

The measuring and verification document created by the partner groups was not yet publicly available, "but the plan is to make it available shortly," said a Walmart representative in an email on Thursday afternoon.

Elizabeth Sturcken, managing director for corporate partnerships at EDF said that that Walmart and their partnering organizations were "trying to find a goal that was aggressive yet achievable," adding that, "what's real important is a change in perspective."

Calling it a move into "uncharted waters," Sturcken noted that the plan doesn't require waiting for the world or the US to act on greenhouse gas emissions and that that the plan is a "good opportunity to get action now."

This is not the first major sustainability announcement in the last year or so for the world's largest retailer. In addition to the goal of being completely powered by renewable energy, Walmart also created a sustainability index that they say will  "measure the sustainability of every product it sells."

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