What happened

The stocks of companies focused on alternative energy development -- and the hydrogen economy in particular -- jumped today, bringing them back into the black for the week. Specifically, as of 3:45 p.m. EDT, shares of electric vehicle maker Nikola (NASDAQ:NKLA) bounced 7.7%, Plug Power (NASDAQ:PLUG) stock was up 5.4%, and Bloom Energy (NYSE:BE) shares jumped 6.75%. 

So what

It's been a fairly volatile week for these stocks, with shares recouping double-digit declines to get closer to breakeven today. 

NKLA Chart

NKLA data by YCharts

That amount of volatility isn't surprising for companies like these that are working to grow the hydrogen economy. And no company-specific news has come out to create today's bounce. But there are signs of progress in growing the feasibility of hydrogen as a fuel source globally, which investors likely take as positive indications for the business plans of Nikola, Plug Power, and Bloom Energy.

A semitruck hauling a tanker of hydrogen fuel.

Image source: Getty Images.

Now what

British power generator SSE and Spanish wind turbine maker Siemens Gamesa announced Monday that they will investigate the potential to develop green hydrogen from two onshore wind farms in Scotland and Ireland, according to a Reuters report.

While this doesn't directly impact the U.S. companies also looking to grow green hydrogen production, the fact that there is a global push in the sector does give the overall industry more support. The potential overseas development aims to "work with green hydrogen customers across industries including transportation, major distilleries and gas network operators," according to the report. 

That, in general, is also what Nikola, Plug Power, and Bloom Energy are working to do. Plug Power recently announced a new agreement to produce green hydrogen, and just last month Nikola said it was investing in a clean hydrogen project in Indiana to support its planned fleet of hydrogen-powered semitrucks in the region. 

For its part, Bloom Energy said last week that it was going to work with renewable energy technology company Heliogen to use solar power and water to produce green hydrogen using Bloom's solid oxide electrolyzers. 

These are all speculative projects, and these companies are counting on a growing global hydrogen economy to realize the potential of their investments. When there is positive news that others are also moving in that direction, investors gain more confidence in the long-term prospects of companies like Nikola, Plug Power, and Bloom Energy.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.