What happened

The stock of hydrogen fuel cell technology company Plug Power (PLUG 2.28%) has been up and down over the last month. Shares have swung as low as nearly $25 per share, and as high as almost $32, ending right back near where it started. But the stock is jumping Tuesday morning on news of a new supply agreement. Plug shares initially popped 7%, and were still trading up 6.3% as of 10:20 a.m. ET. 

So what

Plug has been growing out its network of green hydrogen production capacity, and today announced a deal to offer Walmart up to 20 tons per day of the fuel. The retailer would use the zero-emission fuel to power its fleet of material-handling forklift trucks at its network of distribution and fulfillment centers. The agreement is among the first green hydrogen supply contracts of its kind for Plug Power.

View of forest from above, with a lake in the shape of H2.

Image source: Getty Images.

Now what

Plug Power has been working on a multiyear plan to build a national network of green hydrogen production facilities in the U.S. It has projects ongoing in Georgia, Tennessee, and New York, and plans for the largest such facility on the West Coast in California. Green hydrogen is considered a zero-carbon fuel as it is produced using electricity generated from only renewable sources. 

Jeff Smith, Walmart senior director of supply chain maintenance services, said in a statement, "Sourcing green hydrogen can help bring Walmart closer to reaching our goal of zero emissions by 2040." 

For Plug Power investors, it's a good start to see a market developing for its green hydrogen investments, especially from the world's largest retailer.