It was a quiet day on Wall Street until President Barack Obama pledged in a speech in Brussels that the United States would not stand idly by in the face of Russian aggression against U.S. allies. Just when we thought things were cooling down in Crimea, the market sold off heavily because conflict with Russia would have a terrible economic impact on both Europe and the U.S.

The Dow Jones Industrial Average (^DJI 0.14%) went from nearly a 100-point gain in early trading to falling 54 points, or 0.33%, at 3:30 p.m. EDT. The sell-off was fast and furious at midday. But that volatility is part and parcel of the market; investors with a long-term time horizon, like we recommend at The Motley Fool, can look at the drop as noise to their investments.

Plug Power fuel cell on a Raymond forklift. Source: Plug Power website.

Fuel cells are falling flat
The big move in energy today comes from fuel cell companies, which were some of the hottest on the market in early 2014. Plug Power (PLUG -1.10%) was down 24%, FuelCell Energy (FCEL -4.67%) fell 17%, and Ballard Power Systems (BLDP 0.37%) dropped 22%.

What's interesting is that this comes after a pop in shares yesterday after Plug Power's CEO hinted at a deal with an automaker that would be announced in the next few weeks. But Andy Marsh wouldn't give any information about the deal and today said the order was disclosed during earnings on March 13. That's when management said orders had already reached $60 million of an expected $150 million for 2014. Basically, shares today are just retracing yesterday's gains.  

Ballard is along for the ride because it actually makes the fuel cell stacks that Plug Power uses in its systems, so it's understandable why the two companies would rise and fall together as traders speculate on the potential growth in fuel cells.

But FuelCell Energy has almost nothing in common with these two, instead making fuel cells that are primarily used as backup generators. It's not as easy to make the leap from backup generators to the auto market as forklifts to the auto market, but the market has been carrying FuelCell Energy along anyway.

Can fuel cells live up to the hype?
Let's keep in mind that the auto industry has been researching fuel cells for years, and it's a big leap to think that any of these three companies could offer a huge jump in technology. There's also the fact that they're primarily selling fuel cells to power forklifts and backup generators, not building millions of cells to go into cars. That's not even mentioning the massive infrastructure needed to adopt fuel cells outside of a contained environment.

Fuel cell stocks will jump around, but at the end of the day these stocks are more hype than fundamental value. In fact, none of them are even close to profitable, despite valuations between $500 million and $700 million. Until I see more concrete evidence that the market is as big as traders think, fuel cells are a risk I'm not willing to take.