The announcement of Bloom Energy's low-emissions energy server drew the world's attention to Silicon Valley yesterday. But, even after the announcement and demonstration, many questions remain. (editor's note: term changed to the more precise "low-emissions," 4:45 p.m. February 25, 2010.) 
 
 Here is some of what we know about the Bloom Energy Server, and what we still need to find out: 
 
 Where did the energy server come from? 
 
 It's from Mars. Or would have been going to Mars if NASA's plans hadn't changed. The fuel cell was developed at the space agency as part of its plan for planetary exploration. It potentially is as important as any other NASA discovery and directly benefits people here on Planet Earth, making it a pretty good investment of tax dollars. 
 
 What makes the Bloom Energy Server special? 
 
 Bloom Energy says its fuel cells have a 2-to-1 efficiency over electric utilities. That fact alone makes the server attractive for many uses, as it allows a unit the size of a parking space to produce 400Kw of electricity using less fuel than a traditional power plant would require. 
 
 So you have to use energy to make energy, what gives? 
 
 Some have focused on the fact that the Bloom server requires a fuel source, such as natural gas, to operate. Many people don't realize that energy is converted from one form or another to make electricity. At the end of the day, solar energy drives almost everything we do. 
 
 Coal and petroleum are created by the decomposition of organisms that lived millions of years ago, and themselves used the sun's energy to grow. The Bloom server converts biofuels or natural gas (along with oxygen) to electricity. 
 
 Who will purchase Bloom's servers? 
 
 Right now, companies that can afford to spend $700,000-$800,000 on a relatively unproven device that supposedly pays for itself, through lower electricity bills, over a 3-5 year period. It helps to have a supply of cheap biogas available, such as from decomposition in a landfill. The units are likely to prove attractive to electric utilities as a replacement for other power generating equipment, which is less environmentally-friendly and may cost more to operate. 
 
 Will there really be a Bloom Energy Server for our homes? 
 
 Who can really say? Bloom is promising a unit that can power a home in 10 years at a cost of $3,000, but that has to be considered speculation given the timeframe and variables. If I were guessing, I'd imagine Bloom servers might appear to power whole neighborhoods and be operated by traditional power companies before the home server appears. It all depends on how the technology and market place develops over time. 
 
 Does Bloom have competitors? 
 
 "There are probably another 100 companies that are working on something very similar," Jack Brouwer, associate director of the National Fuel Cell Research Center told the Los Angeles Times. "But the key thing is that Bloom has an integrated system and package ready for commercial sale that puts them ahead of the pack." 
 
 The potential exists for a competitor to introduce an even more attractive system than Bloom, which was founded in 2001 and spent 9 years developing its server. Wednesday's announcement puts some pressure on competitors to make their announcements, too. 
 
 What don't we know? 
 
 There are several important unknowns about the Bloom Energy Server, including: 
 
 •1. - What is the life span of the server? The individual fuel cells are said to have a long life, but what about the total system? 
 
 •2. - How much downtime will a system have? Google has said its system is operational 98 percent of the time. That's may be OK if you have another power source available, but what if Bloom is the only source? Is the downtime scheduled or a surprise? If you have multiple Bloom servers, are they likely to go down at once? Do whole servers fail or just a single 100Kw module at a time? 
 
 •3. - What do you do with all the heat? While Bloom servers don't emit greenhouse gases, they do produce a lot of heat, potentially limiting their application. Is there some method planned to use this heat? How much additional energy savings might that provide? 
 
 The Bloom Energy Server is certainly an exciting development, but that excitement should be tempered by the challenges it faces, and the likelihood that another company has something at least as exciting in development. 
 
 My takeaway is that energy problems may be more easily solved that previously imagined. 
 
 David Coursey has been writing about technology products and companies for more than 25 years. He tweets as @techinciter and may be contacted via his Web site. ||||| A richly funded clean-energy startup is keeping critical parts of its business plan secret as it launches its first product amid fanfare. 
 
 KR Sridhar, co-founder and CEO of Silicon Valley startup Bloom Energy, holds up a fuel cell at a news conference at eBay offices in San Jose, Calif., Wednesday, Feb. 24, 2010. The company's first product... (Associated Press) 
 
 KR Sridhar, co-founder and CEO of Silicon Valley startup Bloom Energy, holds up a stack of fuel cells at a news conference at eBay offices in San Jose, Calif., Wednesday, Feb. 24, 2010. The company's... (Associated Press) 
 
 The Silicon Valley company, Bloom Energy, didn't offer many new details Wednesday about how it plans to make its promising fuel-cell technology affordable enough for regular people to buy for their homes. 
 
 That's an important question because the company's product _ a box of fuel cells that looks like a giant filing cabinet _ currently costs $700,000. Corporations are the first customers, but Bloom Energy wants to cut the price to a few thousand dollars and put it in homes. 
 
 All CEO K.R. Sridhar would say was that the price cut could take a decade or more as the technology improves, much as computer chips have steadily gotten more powerful and cheaper over the decades. 
 
 "We're very confident we can make the economics work," Sridhar said. 
 
 With around $400 million in venture funding, Bloom Energy is one of Silicon Valley's most closely watched startups. Since its founding in 2001, it has been remarkably secretive about its technology. 
 
 The lack of details even in the official launch Wednesday of Bloom Energy's first product concerned some experts, who said it's not possible yet to measure the true cost of generating power using a Bloom box and to determine whether Bloom Energy's technology is substantially different from other fuel-cell companies'. 
 
 "I would try to take a healthy dose of skepticism. What they've demonstrated is they have these systems and they've been able to deploy them," said Bryan Pivovar, fuel cell group manager of the Hydrogen Technologies and Systems Center at the National Renewable Energy Laboratory. "There's nothing I've seen out of Bloom that makes me believe there's anything special about the way they're putting things together and what their approach is." 
 
 Bloom Energy does claim that its box can produce more energy _ with less environmental damage _ than other fuel cells on the market because it isn't reliant on just hydrogen to trigger the chemical reactions that create power. Rather, it can use wind, solar power and whatever else is available, which could vary from community to community. 
 
 However, Bloom Energy didn't offer more details about how that worked, and Pivovar said that using wind or solar would require an extra step to convert the energy into something that could power the fuel cells, which could result in some energy loss. One of the easiest ways to power the Bloom box would be to hook it up directly to a natural gas line. 
 
 A key detail Bloom Energy disclosed was the price its customers pay for power generated by their Bloom machines, and how much money they save over buying regular power from utilities. 
 
 Bloom Energy said its customers, which include Google Inc. and eBay Inc., pay 9 cents to 10 cents per kilowatt-hour. For power they buy directly from the electricity grid in California, where all of Bloom Energy's boxes are currently located, the price is 13 cents to 14 cents per kWh, the company said. 
 
 The savings are big but there's a catch. Bloom Energy said its customers are getting a big federal tax credit that amounts to 30 percent of the price of the Bloom box, along with a rebate from California based on how much energy they buy. 
 
 The figures suggest that Bloom Energy's customers might be saving money solely because of the subsidies, not because the power generated by Bloom Energy machines is cheaper to produce. 
 
 Bloom Energy didn't break out what the costs would be without the subsidies. Sridhar said the investment pays for itself in three to five years but declined to provide further details. 
 
 The use of subsidies could make the Bloom boxes less economical in markets in which subsidies don't exist or aren't as generous. Sridhar said other states and countries abroad have attractive subsidies as well, but added that a key goal is driving the price of the product down enough so that subsidies won't be necessary. 
 
 "We need to get that subsidy in the early days," he said. "But very early we need to get out of those subsidies. Otherwise we're not going to the developing world like we want to." 
 
 He said the potential market for Bloom Energy's technology is so large that the company could thrive even if it stayed in California. 
 
 "We can grow as fast as we want and serve California for the next five years and be a multi-billion-dollar company," he said. "That's how big this market is." 
 
 Scott Samuelsen, director of the National Fuel Cell Research Center at the University of California, Irvine, said he was concerned that Bloom Energy's boxes haven't been deployed long enough to evaluate their long-term reliability. 
 
 "Most customers are looking for a minimum of five years solid performance with a new technology," he said. "We don't know the minimum. We know almost nothing about the company, almost nothing about the technology, and there are a number of manufacturers around the world doing the same thing. ... It's cause to be cautious and recognize that there's going to be a path that has to be followed that will take some time." ||||| View Images Held by CEO K.R. Sridhar at a Bloom Energy press conference today, a single Bloom Box fuel cell is said to be able to power a light bulb. 
 
 Photograph by Justin Sullivan, Getty Images 
 
 The Bloom Box—an as yet unbuilt in-home "power plant" designed to be about the size of a mini-fridge—could provide cheap, environmentally friendly electricity to U.S. households within ten years, according to Bloom Energy. Or not. 
 
 After days of speculation and hype, the fuel cell company unveiled their plans for Bloom Box mass production—but no prototype—at a press conference today with California governor Arnold Schwarzenegger and former U.S. secretary of state and Bloom Energy board member Colin Powell, among others. 
 
 But fuel cell experts say that, based on the information the company made public today, the Bloom Box technology is not revolutionary, nor is it the cheapest or most efficient fuel cell system available. 
 
 "It's a big hype. I'm actually pretty pissed off about it, to be quite honest," said Nigel Sammes, a ceramic engineer and fuel cell expert at the Colorado School of Mines. 
 
 "It really is nothing new. Go to any [solid oxide fuel cell] Web site and you'll see the same stuff." 
 
 Mike Brown, a vice president at fuel cell maker UTC Power—a competitor to Bloom Energy—also wasn't surprised. 
 
 "I think we had anticipated just about everything that's on their Web site," Brown said. "But it's nice to at least finally see something" after ten years, which is about how long the Bloom Box has been in development. 
 
 In an interview with CBS TV's 60 Minutes Sunday night—which did much to fuel anticipation for today's announcement—K.R. Sridhar, CEO of Bloom Energy, said that, for one thing, the Bloom Box fuel cell system is a much better, or at least more reliable, alternative to solar power as a green energy source. 
 
 Video: Bloom Box Segment From 60 Minutes 
 
 "The sun doesn't shine on your rooftop 24 hours a day," Sridhar said. "Our box produces electricity continually and reliably." 
 
 Fuel cells are devices that combine a fuel, such as natural gas, and an oxidant, such as oxygen, and turn their chemical energy directly into electrical energy. 
 
 Big Bloom Box Already in Use 
 
 For months now, Bloom Energy has been testing refrigerator-size Bloom Boxes at campuses of major corporations—including Google, FedEx, Wal-Mart, and eBay. 
 
 One of these jumbo Bloom Boxes, called Bloom Box Servers, could power a hundred homes, and four of them could power a 35,000-square-foot (3,250-square-meter) office building, Sridhar said on CBS. 
 
 Sridhar, a former NASA engineer, said he hopes to begin selling the mini-fridge-size Bloom Boxes within five to ten years. Each of the small Bloom Boxes should be able to power a household, he said. 
 
 How Bloom Box Should Work, Basically 
 
 At the heart of the Bloom Box will be solid oxide fuel cells—in this case, flat, coaster-size ceramic plates with a secret coating—widely considered by experts to be one of the most efficient types of fuel cells. 
 
 Bloom Box plates—already in use in the industrial models—can each power one light bulb, but a stack of 64 of the cells could be "big enough to power a Starbucks," Sridhar said. 
 
 Oxygen and natural gas would be fed into the Bloom Box and undergo a high-temperature chemical reaction in the fuel cells to produce electricity, heat, carbon dioxide, and water. 
 
 The fuel could be piped in from municipal natural gas systems—much as it is for gas stoves and ovens—or created from biogas or, as in the case of eBay, harvested from natural gas-rich landfills. 
 
 No Reason to Doubt Bloom Box Tech? 
 
 Friedrich "Fritz" Prinz, a fuel cell expert at Stanford University, said there's no reason to doubt that the Bloom Box works as Bloom Energy's Sridhar claims. 
 
 "The solid oxide fuel cell technology they're pursuing is one of the most attractive fuel cell technologies there is," said Prinz, who was not involved in the Bloom Box's development. 
 
 Based on the 60 Minutes segment, Prinz said, the design of the Bloom Box appears to be fairly standard and that there was nothing obviously revolutionary about it. 
 
 "They didn't reveal any new physics or any new principles, but I don't think they need to do that," Prinz added. 
 
 "They just need to take understood and recognized principles in material science and thermodynamics and implement them, and it looks like they've done that successfully. 
 
 "Whether they've done it economically, I don't know." 
 
 Bloom Box for the Budget Conscious? 
 
 The industrial-strength Bloom Boxes now in use cost eBay and other companies between U.S. $700,000 and $800,000. At eBay, Bloom Energy is maintaining the machines under a ten-year maintenance contract. 
 
 eBay CEO John Donahoe told 60 Minutes that the five Bloom Boxes installed seven months ago at the company's campus in San Jose, California, now provide almost 15 percent of eBay's electricity needs. Estimated energy savings for the seven months: $100,000. 
 
 At that rate, the Bloom Boxes should pay for themselves within three years, Donahoe told the business-news site Fast Company. 
 
 A residential Bloom Box should cost around U.S. $3,000, Bloom Energy's Sridhar said—much cheaper than most currently available consumer fuel cell systems. 
 
 "Manufacturing these things cheaply is not easy," said Michael Kanellos, editor-in-chief of Greentech Media, a business-news site specializing in green technology coverage and analysis. "ClearEdge initially sold theirs for $50,000, and they had to raise it to $56,000." 
 
 Those high prices are due in part to the fact that home fuel cell systems have been built by hand and because low demand hasn't allowed manufacturers to achieve economies of scale—for example to negotiate cheaper prices for raw materials in the way that large production runs allow—said Brown of UTC Power. 
 
 Previous systems have also used the precious metal platinum, though Bloom Energy says they've found a way around this—though the details are under wraps—according to Prinz, of Stanford University. 
 
 Bloom Box Safe and Solid? 
 
 It's also unclear how safe and durable the Bloom Box will be, said UTC Power's Brown. Solid oxide fuel cells must operate at extremely high temperatures, and as a result, they often crack or leak. 
 
 For the Bloom Box to become widely adopted by homeowners—who would presumably be nervous about replacing old reliable technology with a new, relatively untested one—the system will need an operational lifetime of about 85,000 hours, or about ten years, Brown said. 
 
 There are commercial fuel cells, such as ones made by UTC Power, that can operate continuously for that long, Brown said. Bloom Energy has not disclosed the operational lifetime of its Bloom Box. 
 
 It's also unclear as of yet how energy efficient the Bloom Boxes are, Brown said. Fuel cell systems in which both the generated electricity and heat are used can be 90 percent or more energy efficient. 
 
 Bloom Energy has not released specific details about the Bloom Box's energy efficiency or specified whether the heat produced by its units can be utilized. 
 
 "We didn't see any evidence of thermal recovery, so we assume it's an electricity-only device," Brown said. "If that's the case, it is somewhere between 45 and 55 percent electrically efficient." 
 
 That would make the Bloom Box only about 5 to 10 percent more efficient than conventional combined cycle gas turbine (CCGT) power plants, Brown said. Such plants create electricity in two phases: first via gas turbines, then via steam turbines, which take advantage of excess heat generated in the first phase. 
 
 Whitney Colella, a fuel cell researcher at Sandia National Laboratories, said the Bloom Box appears to be very similar to fuel cell systems developed by United Technologies Corp. (of which UTC Power is a unit) and FuelCell Energy, Colella said. 
 
 "All of them can run on natural gas, and all of them can run on biogas," she said. "The main difference is that the electrical efficiency [of the Bloom Box] is slightly higher" than the other two, at least according to figures posted online by Bloom Energy today. 
 
 Bloom Energy's Killer App? 
 
 While most experts seem to agree that the current Bloom Box appears to be a fairly standard solid oxide fuel cell system, Bloom Energy has filed patents in recent years that hint at a possible killer feature that could set its future devices apart from the competition, Greentech Media's Kanellos said. 
 
 The patents describe a process for taking the runoff of the main electricity generation—carbon dioxide and water—and using it to produce oxygen and a "methane-like fuel," he said. 
 
 This would essentially reverse the chemical reaction in the Bloom Box—a possibility Sridhar hinted at on 60 Minutes. 
 
 That new fuel and oxidant could be automatically run through the Bloom Box to generate even more electricity—and less waste. 
 
 The big Bloom Energy Servers already in use don't currently do this, but if such a reverse-reaction is possible—and it's not clear that it is—then "it would be huge," Kanellos said.
– Bloom Energy's plans to put a zero-emission energy server into mass production is an "exciting development," writes David Coursey, but the company has loads of work to do before the so-called Bloom Box becomes the game-changer the hype suggests. The company is promising miniature $3,000 servers will be on the market in 10 years to power homes, but that's a long way from the big $800,000 device it's currently pitching to companies. The company didn't offer many details on how it will get there, notes AP, and plenty of other companies are at work on the same concept. One fuel cell expert tells National Geographic he's "pretty pissed" at the lack of explanation and dismissed it as "all hype." Coursey is more hopeful at PCWorld. "Who can really say? If I were guessing, I'd imagine Bloom servers might appear to power whole neighborhoods and be operated by traditional power companies before the home server appears. It all depends on how the technology and market place develops over time."