What happened

Alternative energy stocks were hot yesterday, and The Wall Street Journal may be the reason for it.

In Wednesday trading, shares of fuel cell pioneer and future hydrogen supply chain kingpin Plug Power (PLUG 4.78%) jumped more than 4% in early trading before giving back much of its gains. The stock closed up less than 2%. Rival fuel cell operator Bloom Energy (BE 4.49%) closed up 10%, while solar power system producer SunPower Corporation (SPWR 5.91%) closed on Wednesday up 9% over the previous day's close.

Collage of windmills, solar panels and electric lines representing the renewable energy industry

Image source: Getty Images.

So what

There was no news specific to any of these three companies out on the wires yesterday. But on Monday, an article  in The Wall Street Journal sang the praises of alternative energy companies in general, asserting that investors have "learned to love wind and solar power."  

As the article said, renewable energy "has become cheap and now offers investors utility-like returns," such that at present, solar power and wind power (generated onshore, at least) now cost less to produce than electricity generated from burning either coal or natural gas.

Nor is this a function of government support. The Journal article said that even without subsidies from the government, renewable energy from multiple sources is now "routinely at least as cheap as fossil fuels," and this is spurring large corporations to sign long-term power supply agreements with producers of renewable energy.

Now what

Are the gains in share prices yesterday sustainable? With the price of solar panels down 80% over the past decade, and even wind turbines costing half what they used to, I think there is a bright future ahead, for solar and wind energy stocks, at least. I cannot help but notice, however, that the Journal article neglected to say anything positive about fuel cells as an investment.

Perhaps one reason for this is that, for five straight years, fuel cell stock Bloom Energy has failed to earn any profit and Plug has been profitless even longer. In contrast, SunPower turned profitable last year, and has reported positive net income of more than $110 million over the past 12 months.