5. Fuel Tech
> Segment: Clean coal and air pollution control
> Share Price: $5.94
> 52-Week Range: $3.55 to $9.63
> Market Cap: $135 million

Fuel Tech Inc. (NASDAQ: FTEK) is in the business of cleaning up the messy process of coal-fired power plants and catering to utility, industrial and municipal solid waste customers. The company also has recently just acquired PECO-FGC, expanding its offerings to include particulate control solutions. The anti-coal policies of late have not helped, but these same regulations perhaps offer Fuel Tech a huge potential down the road. In short, this company helps dirty energy be less dirty.

One issue that always got in the way during the 2007 to 2008 clean-tech boom was that the power plants either would not pay up or the systems were too expensive. Fuel Tech now touts that it enables its customers to operate efficiently in a cost-effective and environmentally sustainable manner.

The company’s revenues have not grown anywhere near as fast as we might have hoped, rising to $109 million in 2013 from $82 million in 2010. Still, the company has run itself with profitability for at least the past four years, and the handful of analysts covering it expect profits in 2014 and 2015. Sales are expected to dip in 2014, only to rise to almost $116 million in 2015. It still has $45 million in accumulated losses that can offset future earnings.

Fuel Tech’s air pollution control technologies are installed worldwide on more than 900 combustion units. The company was founded back in 1987 and is based in Warrenville, Ill., and has two more U.S. locations, with its international offices in China and Italy. With so many emerging markets using coal-powered plants, the next three decades could focus internationally rather than the United States.

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6. Ocean Power Technologies
> Segment: Oceanic Wave Energy
> Share Price: $1.64
> 52-week Range: $1.50 to $7.01
> Market Cap: $21 million

Ocean Power Technologies Inc. (NASDAQ: OPTT) makes proprietary systems called PowerBuoys, which generate electricity by harnessing the energy of ocean waves. Before getting too excited here about this renewable energy subsector, Ocean Power Tech is by far the most speculative of those we have featured here. It has very fresh corporate governance issues after firing its CEO for claims tied to a project. We must also warn that law firms have been loading up class action suits due to serious investor losses sustained at the start of June.

UPDATE July 15, 2014: The fears of Ocean Power’s risks have grown, and the pact announced in Australia has been cancelled. Shares were at $1.20, and this company’s prospects look to be dwindling with more word of class action suits.

All caveats aside, Ocean Power has perhaps one of the most interesting stories for the years ahead, even if that “story” remains future rather than history. The company claims that no anticipated financial restatements are likely, but we do leave this as an open-ended possibility and consider it a risk.

This company came public in 2007 and briefly traded above $15, but a lack of revenue and the alternative energy peak in 2008 kept the stock from ever taking off. It is too small for most analysts, but one boutique in May of 2013 gave this a Strong Buy rating and $5 price target, based mostly on it being under its implied value, noting that its technology, intellectual property and knowledge could be worth $50 million, even if the rest was worth almost zero.

Sales are negligible at this time, but the partnerships and projects are underway to the point that revenues will start coming, as long as the corporate governance woes are not worse. The company’s $21 million market cap is not that much higher than the $16 million book value and cash value, but that is before the class action suits come into play. It also has almost $150 million in cumulative losses since inception.

Again, Ocean Power Tech is the most speculative of all these renewable and alternative energy companies we are featuring. Partners include the U.S. Navy, Mitsui and Lockheed. Ocean Power is based in Pennington, N.J., but it has projects in Hawaii, Scotland, Australia, Japan and elsewhere.

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7. Renewable Energy Group
> Segment: Biofuels and renewable chemicals
> Share Price: $10.98
> 52-Week Range: $8.51 to $16.50
> Market Cap: $426 million

Renewable Energy Group Inc. (NASDAQ: REGI) is into biofuels and renewable chemicals, and this is by and large focused on the U.S. markets. This is not just a tax play for ethanol and other mandated chemicals. The company converts natural fats, oils and greases into advanced biofuels and converts diverse feedstocks into renewable chemicals. The company has recently celebrated the 1 billion gallon milestone for its biofuels production. It even recently completed two acquisitions: Dynamic Fuels and Syntroleum (via Tyson Foods).

This company came public in early 2012 and fell from $10 to $5, but then rose to over $15 before settling down into a trading range of $10 to $12 from late 2013 up through the first half of 2014. REG had liquid assets from cash, cash equivalents and securities of $136.1 million, but it has since raised $125 million from a convertible preferred offering with a $13.26 conversion price, with $100 million or so used to replace a letter of credit after two acquisitions.

Renewable Energy also has only a few analysts that cover the stock. With shares close to $11 as is, the lowest analyst price target is $11 and the highest is $16. Sales were $216 million in 2010, growing to $824 million in 2011, and they were $1.49 billion in 2013. Before thinking that this one is a massive growth engine, the company’s volume is up but lower sales prices are hurting revenues. The company even said its first-quarter results reflect a very challenging quarter coming off an outstanding 2013 — revenue decreased by 17% and adjusted EBITDA decreased by 91%. Still, the company has accumulated $236 million retained earnings over its life.

Renewable Energy group has run into a bump in the road on realized prices, but higher fossil fuels pricing may help that along. The company is based in Ames, Iowa. It has four other regional offices, 10 refining operations around the country and more than 25 terminal locations.