Plug Power (PLUG  ) is one of the best-performing stocks this month and this year. The company has benefitted from a variety of catalysts. It's also enjoyed a positive tailwind from the overall strength in EV and alternative energy stocks. Second, it's business has continued to experience momentum with its forklift business.

However, there's now increased excitement that it will be able to apply its fuel cell technology to passenger vehicles, commercial transportation, and power generation. Another catalyst is expectations that a Biden administration would reward companies who invest in "green energy" which could lead to an increase in Plug's sales.

PLUG's Strategy

At one time, Plug Power's strategy seemed far-fetched. The company was using its fuel cell technology to make forklifts. This would fund the continued development of Plug's fuel cell technology which then could be used for applications in larger markets. However, Plug's forklifts have gained significant traction. They are also superior to traditional forklifts in terms of capacity and range.

The forklift market is a $30 billion market. Revenue from forklift sales has funded continued R&D into improving its fuel cells. Now, the company wants to attack bigger markets. Plug uses hydrogen power which many believe is the ultimate "clean energy" and will be the final solution, while other sources of renewable energy are intermediary solutions.

Q3 Earnings

Plug Power is not profitable as it continues to invest in growth. And, the market has been rewarding this decision as it focuses on other metrics. In Q3, revenue was $107 million which was an 80% increase from the previous year and above expectations of $106.5 million. Gross billings also beat expectations at $112 million.

The company also raised full-year guidance for gross billings to $330 million. Gross margins also improved as increased production lead to falling costs. Currently, the company hopes to build 5 hydrogen plants by the end of 2022 which signals confidence that hydrogen fuel cell demand will continue to grow.

Stock Price Outlook

YTD, Plug's stock is up 718%. MTD, it's up 50%. There's an active discussion in the market about whether or not cleanTech stocks are in a bubble or not. It's certainly possible given the gains and valuation.

Plug Power has an $11 billion market cap and $300 million in sales. However, there are many stocks that have seen similar gains in price which don't have sales or an actual product. Compared to these companies, Plug is in much better shape as it has a significant share of the global forklift market, and multiple partnerships with reputed companies to apply its fuel cell technology to other uses.