Bill Kurtz, former AT&T VP and current CFO of Bloom Energy, said that the cleantech company is "halfway there" to profitability in an interview with GigaOM last week. It was back in 2010 that the company's Bloom Box made headlines with its ability to convert natural gas directly into electricity without any form of combustion, and since then the company has expanded rapidly. Kurtz said that Bloom Energy is doubling its number of installations and revenue every six months, and that the company's biggest challenge right now is managing its accelerating growth rate.

The Bloom Box has been bit a hit with datacenters, landing big-name clients like Apple and eBay in recent years. With Amazon having had a significant power interruption to a section of its datacenter — causing services like Netflix and Instagram to go dark for several hours — it isn't surprising that the Bloom Box's redundant, solid-state fuel cells are becoming an attractive alternative to traditional grid power.

Kurtz told GigaOM that "we've made a lot of progress reducing costs," and while developing a new technology like fuel cells with promises of high reliability for commercial clients likely isn't cheap, Bloom Energy backer and NEA venture capitalist Scott Sansdell said the company is driving costs down at the expected rate. This rapid but predictable growth bodes well for the up-and-coming cleantech company, which has raised over $800 million in its 10-year lifespan.