The new energy bill just passed by Congress -- and oil hitting new highs -- may be providing some of the fuel sending old, almost-forgotten energy technology stocks to 52-week highs.

Microturbine manufacturer Capstone Turbine (NASDAQ:CPST) was up almost 30%, and left its old 52-week high well in the distance, yesterday as CEO John Tucker said that the bill "contains a 10% tax incentive for businesses to buy and conserve energy with microturbine generators." But that is not all.

Tucker also said, "It also offers users of advanced microturbine energy systems direct payments from the U.S. Department of Energy for every kilowatt-hour they generate. This policy, and others in the energy bill, will create significant additional economic advantages for customers who invest in microturbines, beyond the everyday savings and energy reliability inherent in microturbine technology."

Capstone is a story stock that has had a nasty fall. Look at this chart and notice that five years ago, the stock was peaking at $98.50 -- and, while yesterday's new 52-week high at $3.45 sounds good, it is certainly not anywhere close to the highest price ever.

But order rates turned around last year, as revenue climbed and the company's net loss declined. Recent order announcements (before the new energy bill) were encouraging. Now, with new incentives in place, orders should be easier to get. Ah, but don't jump to the conclusion that profits are around the corner. Analysts still do not expect the company to turn a profit over the next two years -- and there is big competition from Ingersoll-Rand (NYSE:IR).

Also, Beacon Power (NASDAQ:BCON) was up 50% recently on news that its flywheel technology (with the potential to prevent giant blackouts like the one in North America in 2003) has been successfully tested and is now ready for shipment for "grid-connected performance demonstrations." For perspective, grid reliability has become a high priority given recent events, and the energy bill tries to target this.

While Beacon was never the highflier Capstone was, its stock's five-year performance is equally disappointing. One reason for that can be seen in the company's first-quarter results: Revenue, at $636,000, was less than one-third the reported loss of $2.2 million. How's that for burning cash?

Even worse, the company, though debt-free, has only $3.3 million in cash. While demonstration systems heading for field testing is good news, the one analyst that follows Beacon does not expect it to reach profitability in the next two years. Simply put, the company probably needs to sell equity or borrow money to survive.

Companies with new energy technology have significant potential. But before getting too excited about a company's story, make sure you understand the technology risk and competition before making speculative investments.

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Fool contributor W.D. Crotty does not own shares in any of the companies mentioned. Click here to see The Motley Fool's disclosure policy.