Though fuel cells have been around for over 160 years, the technology is finally becoming more viable.

According to the US Department of Energy, fuel cells have the potential to revolutionize the way we power our nation, offering cleaner, more efficient alternatives to the combustion of gasoline and other fossil fuels. Fuel cells have the potential to replace the internal combustion engine in vehicles and to provide power in stationary and portable power applications, because they are energy-efficient, clean, and fuel-flexible. Hydrogen or any hydrogen-rich fuel can be used by this emerging technology. Fuel cell companies are working hard to develop backup power for the telecommunications industry, and each is approaching the task in a different way.

Proton Energy Systems Inc., based in Wallingford, CT, is ready to get the word out that hydrogen fuel cells are more than just an alternative automotive fuel. Hydrogen has a myriad of other applications—including fuel cells for the telecom industry, which Proton is poised to enter commercially.

Proton designs, manufactures, and sells hydrogen generators that use PEM electrolysis. Proton derives its hydrogen from water, where electricity is used to separate the oxygen from hydrogen. This is a regenerative system in which Proton’s product generates hydrogen in one direction and then uses that hydrogen in the opposite direction to provide power.

According to Mark Schiller, Proton’s vice president for business development, backup power for telecoms is falling short. Lead acid batteries, which have issues concerning the amount of backup time that’s available when there’s a power outage, are also extremely maintenance-intensive, and often that maintenance isn’t done. “The battery that you’ve purchased within the past two years may have to be replaced and disposed of,” says Schiller.

Another issue has been the weather. The damage done by recent hurricanes has meant power has been out for extended periods over large areas of the United States. The telecoms are forced to manage how they might get their networks back up once again; downtime for those networks involves millions of dollars in costs. They’re looking for other solutions that can give them longer backup power during downtime after catastrophic events like hurricanes.

“What we’re looking at doing with a hydrogen-generation fuel cell as a power solution is extending the backup power time when there is a power outage, as well as extending the life of the product that ultimately goes into that segment.”

Proton Energy has used its proprietary PEM electrolysis technology to create its HOGEN hydrogen generation systems. HOGEN systems are shipped completely assembled and ready to install. Customers supply electricity and de-ionized water (and cooling water for the H series generators). Though good tap water can be used for electrolysis, Proton recommends de-ionized water because it extends the reliability of the product. PEM sells a de-ionized water unit. “It’s a small unit, doesn’t take up much extra footprint, and is actually very small in terms of the incremental costs of the overall system,” says Schiller.

The cell stack assembly is at the core of the HOGEN hydrogen generation system and is composed of individual membrane assemblies arranged in a stack where water and electricity are brought in to produce hydrogen gas. De-ionized water flows into the positive side of the cell where it is dissociated by electrolysis into protons, electrons, and oxygen. The oxygen is carried away by the water flow.

The positively charged protons are attracted to the negative side of the cell. These protons use the sulfonic acid ion groups embedded within the membrane as the path to travel through the solid material. Meanwhile, the electrons flow through the power supply to the negative electrode, where they link up with the emerging protons to form molecules of pure hydrogen gas. This is done at process pressure, without mechanical compression and without caustic electrolytes.

Because of the PEM technology, Schiller says, the hydrogen obtained is five-ninths pure or better. “Anything 99% pure is considered two-ninths,” says Schiller. “Every extra nine added to that percentage adds another amount to the fraction, so that 99.9% is three-ninths, 99.99% is four-ninths, and so on. Most measuring devices cannot detect anything beyond five-ninths; that’s considered ‘medical grade’ hydrogen. Ours is better than you will get if you purchase bottled hydrogen or traditional deliveries of hydrogen. Though you can buy medical grade hydrogen from gas companies, it’s very expensive.”

Varied Applications
The commercial products Proton has available are aimed at a number of commercial applications, including laboratories, power plants, meteorological applications, the semi-conductor industry, and the food-processing industry.

Wallingford Electric with substation

Proton continues to search for opportunities in fueling, backup power, military, aerospace, and those based upon renewable sources of power, such as wind and solar.

Proton has done work for various governmental agencies involved with power systems for unmanned underwater vehicles or even unmanned aerial vehicles.

Storage is an area of significant development for many companies involved with hydrogen, though not so much for Proton, according to Mike Spaner, Proton’s backup power program manager. “Because hydrogen is generated onsite, our system replaces the need to transport compressed hydrogen, which right now is not something everyone does,” says Spaner. “Therefore instead of slinging bottles to and from a site, now, depending on water storage options, you may only have to visit the site once every six months or so. The only item you are transporting now is de-ionized water—instead of hydrogen.” With a regenerative fuel system, as the hydrogen is used up, and once the regular power comes back on, electrolyzing begins, and tanks start to fill up with hydrogen.

“An analogy might be a home gas grill,” says Spaner. “When your tank is empty you must either get another tank or have it refilled. But wouldn’t it also be nice if trickle-charging of the gas tank could take place or once there is grid power available you could simply generate your own propane? You can’t do that yet; but you can do it with water by electrolyzing it, and then deriving hydrogen as an end product.”

An added benefit of hydrogen over propane or natural gas is that the latter have carbon content; electrolyzed water does not. Use of renewables such as wind or solar power can decrease the carbon footprint further. Even the cost of the fuel may be taken into account. How much fuel is being used to send a gas truck to the site? The site itself may be remote and inaccessible enough to make transport of hydrogen bottles problematic, according to Spaner.

“Most cell tower sites are not exactly right on the side of the road,” says Spaner. “Also, our fuel cell systems run into none of the temperature problems that batteries do. The batteries typically have deterioration in the life of the battery at temperatures over 68 degrees Fahrenheit; ours are fine at hotter temperatures. In fact our electrolyzers run more efficiently at 50 degrees Celsius, [or 122 degrees Fahrenheit].”

For backup power for telecoms, Proton is in the stages of developing a solution that is an integrated product involving the hydrogen generation already in place and a fuel cell for backup power to extend the range out to what the telecom companies are requiring.

Proton plans on starting production within the next two years. “We expect to have prototypes ready before then,” says Schiller. “That solution is based on a commercial fuel cell partner already selling fuel cells and our electrolyzers, which are commercial. We are working with two commercial products and trying to figure out a way to optimize all our options.” The system for telecom backup power will be approximately the size of a dishwasher. The electrolytes and the fuel cell will be integrated into one box.

“We are currently doing field testing right in our area. But the effort that we are going through now is one of the heaviest efforts we’ve ever done before, involving several telecoms covering the whole spectrum in both the US and outside of this country.

“We must get this technology in hands of the telecoms now so that by the time everything is ready—in about two years—we have the right attributes for our product. We want to meet their needs.”

Though Proton has a mature line of products involved with hydrogen generation, Spaner and Schiller are involved with the next generation of products, both new and emerging technologies. “We have various backup power applications at present,” says Spaner.

“One of these is a utility substation backup power application. This is not far from our facility here in Wallingford, in the vicinity of the utility substation. It’s a demonstration system backing up to 15 kilowatts of load for an office building. Being a regenerative fuel cell system, it has three 5–kilowatt fuel cells as well as a high-pressure electrolyzer generating hydrogen when grid power’s available and the tanks need to be filled.”

The original installation has VRLA batteries. Proton also has demonstration systems that contain ultra capacitors because fuel cells do have a 20- to 30-second startup time; but because a backup system always has to provide continuous backup power there is always some means of bridging the power. “We like ultra-caps,” says Spaner. “It totally eliminates battery maintenance.”

If traditional sources of energy are used to create hydrogen, the net gain is not as significant. “But the beauty of our technology is that when you are making hydrogen from renewable sources, which is what our product lends itself to—such as wind or solar—then you have a substantial gain,” says Schiller. “Our product technology does a very good job of following the intermittent power provided by renewable sources such as wind or solar. We have the opportunity to create a renewable-based fueling solution that is truly clean.”

Direct Fuel Cells
“Telecommunications is one place where distributed power generation fits along with other applications, says Andy Skok, executive director of strategic marketing with Danbury, CT–based FuelCell Energy Inc. “At Deutsche Telecom in Munich, we have a unit that has been running for several years now, in addition to nearly 50 units running around the world for other target markets. Telecom is something we focus on from time to time.”

FuelCell Energy’s system is second generation technology that is carbon-based and is also a higher temperature technology, more efficient, usable, and commercially available than some of the others, according to Skok.

“It is the current state of the art involving what we call the direct fuel cell,” says Skok.

FuelCell Energy’s products are called “direct fuel cells” because, unlike other fuel cell technologies, they can use hydrocarbon fuels without the need to first create hydrogen in an external fuel processor. “In our case we run off natural gas and then steam ‘reform’ it. Traditionally steam reformers have been used externally to create hydrogen for placing in the fuel cell.”

Some 25 years ago the company patented the idea and developed the technology which in effect takes natural gas and does the steam reforming inside the fuel cell at the same time it’s doing the fuel cell electrochemical reactions. The direct fuel cell reforms natural gas inside the fuel cell to make its own hydrogen.

“We found a way to work around the lag time that’s been involved in having a so-called hydrogen infrastructure up and running and which to date hasn’t yet materialized,” says Skok. “In our case the grid becomes the backup power for what is in effect a noncombustion process.

“Also, our power plants are qualified to Carb2007 today, and they are 1741 and California Rule 21–certified compliant. Therefore, you can do a plug-and-play interconnect with the utility. Places like South Coast Air Quality Management District in Los Angeles don’t require us to obtain an air permit, because ours is a noncombustion technology.”

The internal reforming and the direct concept set this technology apart from all the other fuel cells, according to Skok. Fifteen years ago, phosphoric acid was used for fuel cells.

“That has faded away, and those fuel cells operated at a lower temperature and lower efficiency,” says Skok. “Ours is 25% to 30% more efficient than the others that used to be available; the higher temperature creates a higher-grade waste heat; i.e., you can create steam with it or do adsorption chilling—something the telecommunication industry likes because its form of cogen typically has a high air-conditioning load.”

The FuelCell Energy system running on natural gas provides cooling, which is more valuable to the telecoms than heating, according to Skok. “The PEMs do start and stop quickly, so they have a play in the standby backup market against something such as a diesel reciprocating generator or something like it,” says Skok. “We’re a baseload, grid-interconnected power; if the grid goes down, we just keep running.

“On the order of 20% to 40% of the standby generators out there never start when the power goes out. Another 20% to 40% are not running if the power outage is more than 24 hours. Typically units don’t start because the battery’s dead and the diesel doesn’t come on, and someone may come out and get it started. We solve that problem because if the grid goes down there’s no question about the unit starting—it’s already running. That whole argument goes away 99.9% of the time.”

Skok says that even during blackouts, natural gas is often available the whole time. Natural gas typically keeps running and does not rely on the infrastructure for delivery during a blackout, as with diesel fuel. FuelCell Energy’s units also run off propane, so a cylinder of any size can also be onsite as a backup.

“Our smallest unit is 300 kilowatts in size, so many of the small telecom centers aren’t really what we’d be looking at,” says Skok. “We are looking at the larger switching stations, for areas with the infrastructure who are mainly just worried about the power going out.”

FuelCell Energy has been around since 1969 and has been developing this technology and this particular fuel cell type since the late 1970s. “We are perhaps more atypical than most fuel cell companies, a business that’s into fuel cells, rather than a fuel cell company. We were addressing issues with the PEM technology back in the 1980s,” says Skok.

“The standard response from the distributed energy generation industry is not to recognize fuel cells as a solution for commercial applications. Ask someone about fuel cells and they’ll respond that their kid’s going to drive a car with a fuel cell someday. Our biggest problem at a sales site is not to be taken as a credible solution; therefore, when a RFP [request for proposal] goes out we will end up competing with reciprocating engines.

“But we are an expensive, much more efficient nonpolluting technology. Our 40 Ph.D. electrochemical engineers working for us have played around with every type of fuel cell under the sun. They’ve even invented new types of them. Who knows what’s going to happen out there?

“The bottom line, however, is that we make energy more efficiently than anyone else. We are a baseload system, not a backup. We make more electricity for less natural gas than anyone else. As the price of natural gas goes up, we become more competitive instead of less competitive; in other words, [we provide] an energy conservation measure using natural gas, and we can do that without any pollution at all.”

Beta Testing This Year
Mike Vukovinsky is director of onsite products and applications for United Technologies Corp.’s onsite product development teams for its stationary business. This includes the company’s backup fuel cell module for the telecommunications market. United’s system operates off compressed hydrogen from bottles. “Our target market initially is the telecommunications market,” says Vukovinsky. “This is for backup power for cell towers, data centers, and communications huts. The module size is rated at 5-kilowatts continuous.”

UTC’s alpha unit was tested extensively last year. For beta testing it has 20 units that it plans to put in the hands of customers this year, along with its laboratory testing proceeding at the same time. “With both the laboratory and ‘real-world’ testing going on, we’ll fold all that information into our production release,” Vukovinsky says.

A “K” size bottle is roughly the same size as that used for any acetylene torch. “That bottle can operate the unit, rated at 5 kilowatts for approximately 1.2 hours continuously,” he adds. “Depending on the customer’s need for backup power, we will bring in additional bottles as required.” A typical cell tower providing 9-1-1 services requires eight hours, or seven or eight bottles of hydrogen, according to Vukovinsky.

“Via our beta testing, we’re hopeful that we get the kind of response we’re expecting: perfect reliability on start, a unit designed for zero load-disruption on the customer side, and controls designed such that, if power fluctuates in any way from the grid, we provide the net power to the customer without any electronic interruption.”

UTC has a stationary fuel cell product rated at 200 kW that has a built-in integrated steam reformer as well, so the unit runs off pipeline natural gas. “We don’t have to purify the reformate coming out of the steam reformer; the cell stack is capable of handling the reformate as is,” says Vukovinsky. “We use a different technology there with a phosphoric acid technology. That has been in production since 1992 and we have over 260 of those units deployed worldwide. We have 1.2 billion kilowatt-hours of accumulated experience throughout the world in fuel cell technology—19 countries and five continents.”

UTC also works with alkali for space technology, stationary products, continuous duty natural gas products, and automotive and fleet vehicles, all featuring a proton-exchange membrane, as well as the company’s 5-kW backup power solution for telecommunications. “The technology for this unit,” says Vukovinsky, “goes back, actually, all the way to the Apollo space program, where we’ve been sole-sourced to NASA for fuel cell source for the power of the vehicle for all manned space flight since Apollo 1.”

Peter Hildebrandt is a writer specializing in science and engineering topics.

DE - January/February 2007