[caption id="attachment_96807" align="aligncenter" width="500"] The Bloom Energy Server of fuel cells takes up the equivalent of one and half parking spaces behind the hospital but is designed to supply the power needs of the Sutter Santa Rosa Medical Center with few emissions. (credit: Sutter Health)[/caption]

SANTA ROSA -- Sutter Health's new hospital just north of Santa Rosa will leap into a clean energy future at its planned opening Oct. 25, using secretive Bloom Energy fuel cells to produce about 70 percent of its electricity needs.

The compact fuel cells, sized to generate 375 kilowatts of power continuously, occupy barely 1,000 square feet outside the Sutter Santa Rosa Regional Hospital building. They turn natural gas and air into power in an electrochemical process without burning, releasing less carbon dioxide than electricity made from coal-burning generators.

The total output of electricity over a year will be about 3 million kilowatt-hours. The hospital plans to buy natural gas from PG&E.

[caption id="attachment_96729" align="alignleft" width="245"] K.R. Sridhar, Bloom Energy CEO[/caption]

Bloom Energy, based in Sunnyvale, was co-founded in 2001 by K.R. Sridhar, who invented a device intended for use by NASA to produce oxygen on Mars. The company added Steve Case, former chairman and CEO of AOL, to its board on Aug. 12.

The fuel cell technology fits into a world in flux: Laptops, portable and decentralized, supplanted desktop computers in offices. Smartphones eclipsed land lines tied to central phone switches. Finally, onsite fuel cells, decentralized by design, are replacing grid delivery of electricity.

[caption id="attachment_96730" align="alignright" width="207"] Lisa Amador, Sutter Santa Rosa Regional Hospital's strategy and business development executive, says, "It's fascinating," about the Bloom Energy fuel cell project for the new hospital.[/caption]

"It’s incredibly efficient," said Lisa Amador, Sutter’s strategy and business development executive. But what happens inside the fuel cells is a mystery. "It’s top-secret."

Bloom takes ordinary sand and bakes it into ceramic disks then coats them on both sides with special green and black ink. A stack of these disks forms a fuel cell, each a cube about 4 inches on a side. A couple of cubes can power a house.

Natural gas is not burned by the fuel cells. The electrochemical reaction reduces carbon dioxide output and nearly eliminates other particulate emissions caused by burning fossil fuels. Bloom estimates that Sutter's carbon footprint will drop by 600,000 pounds a year, and water consumption will be reduced by 17 million gallons.

The alternative energy project cost about $3 million to $5 million, Ms. Amador said, out of a total hospital construction budget of $284 million. The project is on time and on budget.

Bloom will service the installation at Sutter from remote monitors located in Silicon Valley and India.

Since its founding, Bloom Energy has attracted nearly $1 billion in venture funding, initially from Kleiner Perkins Caufield & Byers, which started with about $100 million in a deal orchestrated by venture capitalist John Doerr.

Bloom Energy landed Google as its first paying customer in 2008, followed by Netscape, Amazon, eBay, Wal-Mart, Staples the National Security Administration and others. All its installations total more than 130 megawatts. The largest is a 27-megawatt utility installation.

Generous state and federal subsidies helped entice these companies into trying fuel cells to meet part of their energy needs. Sutter is among the first North Bay customers of Bloom Energy, according to Ms. Amador.

Bloom joined with the gigantic SoftBank, a $70 billion Japanese technology investment company, last year to bring its fuel cells to Tokyo.

The Sutter hospital fuel cell installation is protected by "big cement posts so people don’t back up into it" with their cars, Ms. Amador said.

The technology produces direct current, like that used in cars. Bloom's equipment has built-in inverters, which turn the direct current into alternating current like that provided by the grid. Fuel cells are projected to last 10 to 20 years.