What happened

No -- the usual suspects aren't rearing their heads today, and the markets writ large aren't uncharacteristically bullish. It seems curious, therefore, that shares of fuel cell and hydrogen specialist Plug Power (PLUG 1.47%) are rising strongly today. In fact, it's not a notable news release from the company or favorable commentary from an analyst but an announcement from hydrogen industry peers Nikola (NKLA 7.35%) and Chart Industries (GTLS -0.60%) that's behind the pop in Plug Power's stock.

As of 11:35 a.m. ET, shares of Plug Power are up 3.7%, ebbing from their earlier rise of 5.2%.

So what

Nikola, a manufacturer of hydrogen-powered vehicles, and Chart Industries announced today that they have executed an agreement regarding hydrogen storage and related equipment. According to the announcement, Chart is also "providing first-of-kind fully integrated mobile and modular hydrogen fueling stations for heavy-duty vehicles providing a quickly deployable fueling solution with lower capital requirements."

Plug Power investors are sitting up and taking notice of the collaboration between Nikola and Chart for a couple of reasons. First, it suggests that the hydrogen economy in general is gaining momentum -- something critical for Plug Power in order for it to achieve its lofty growth targets.

More specifically, though, the agreement is noteworthy considering Plug Power's relationship with Nikola. In December, Plug Power and Nikola announced a deal that would see Plug Power begin to supply hydrogen to Nikola beginning in 2023 and with volumes ramping up to 125 tons per day. Nikola's deal with Chart may assuage the fears of investors who wondered whether Plug Power's deal with the company is in jeopardy considering the rocky road Nikola has recently encountered.

Now what

While companies such as Nikola and Chart are forging ahead in pursuit of developing the hydrogen economy, investors should recognize that an ocean exists between news announcements and strong financial growth. In other words, investors should look for concrete improvements in Plug Power's financials as a bullish sign -- not merely positive news from its partners.