6. Bloom Energy
Founders: K. R. Sridhar, John Finn, Matthias Gottmann, James McElroy, Dien Nguyen
Launched: 2001
Funding: $1.1 billion
Valuation: $3 billion
Disrupting: Energy, utilities
Rival: Legacy electric grid
Just as mobile phones replaced landlines and personal computers replaced large mainframes, Bloom Energy's aim is to lead the energy industry away from a traditional "hub and spoke" network to a clean, distributed, and more reliable energy model. The company, headquartered in Sunnyvale, California, uses fuel cells to convert natural gas into electricity, and then places those power source units in office buildings, retailers, data centers, and other customer locations, including Apple, AT&T, Walmart and The Home Depot, to name a few.
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In fact, in the past few months it has clinched two high-profile deals: to power Morgan Stanley's headquarters in Times Square in New York City, and AEG's Staples Center sports arena in Los Angeles. Investors, including heavyweights such as Kleiner Perkins Byfield & Byers and New Enterprise Associates (NEA) have poured over $1 billion into the company since it started in 2001. And therein lies the question: How much longer will the company remain private? Many investors expected an IPO in 2013, and when that didn't happen, they figured 2014 was the year.
The company doesn't seem fazed by the speculation and points to its commanding position in the global market for electric power — a $2-trillion-a-year industry poised to grow 80 percent by 2040, driven by increased demand in developing countries. Even with that rosy outlook, observers can't help but wonder what the ultimate fate is for this 15-year-old company. Venture capital firms typically look for a hefty return on investment within a decade. So far this year there is hardly a hint of an upcoming IPO. With that measure, Bloom is on borrowed time.