Are Stationary Fuel Cells Ready for Market? Daniel Bullock Atul Kumar Karl Rábago Houston Advanced Research Center For a number of years, many energy technology experts believed that stationary power generation would be a logical early adopter application for fuel cell systems. The belief that early adoption would take hold in stationary applications resulted from a number of factors thought to reduce the barriers to adoption relative to either vehicle or portable applications. Arguments supporting early adoption of stationary fuel cells often alluded to the following three factors: • the relatively widespread availability of natural gas addressed the questions about the sources of hydrogen fuel; • the relatively less demanding requirements for volumetric and graviometric power density allowed stationary fuel cells to be operated under more favorable conditions; and • the relatively high prices paid for electrical power service provided more incentive for deployment. However, these factors have not had the strong driving effect originally anticipated. The first factor, natural gas availability, has not emerged as a significant driver due to the high cost and less than fully satisfactory performance of reformer technologies. Fossil fuel reformers bundled with proton exchange membrane (PEM) fuel cells have added both cost and complexity to PEM stationary systems, reducing the range of application opportunities. Solid oxide technologies, an alternative that doesn’t need external reformers, have yet to emerge from the laboratory as real competitors. Less demanding requirements for power density also turned out to be insufficient to drive the technology. The original logic was that low power density requirements allowed PEM fuel cells to be operated at lower pressure and temperature. While this should have increased the durability of the fuel cell stack and thereby improved the cost-effectiveness of PEM systems, the use of hydrogen reformate, with its high concentrations of CO and sulfur, has tended to offset operational benefits. As a result, PEM systems marketed into stationary applications fell well short of the 40,000 hour operating life required in the application. While small fuel cell systems have found success in a few high value applications, the slower than expected rate of adoption significantly impacted hoped-for drastic price reductions associated with manufacturing volume increases. And addressing technical issues meant that scarce capital resources had to be invested at a higher

than expected rate for technology development. While prices have definitely fallen in recent years, uncertainty lingers regarding whether significant market demand will materialize at these lower prices and whether manufacturers can produce units profitably at those prices. So where does the commercialization of stationary fuel cells stand today?

End User System Testing Commercialization of stationary fuel cell systems will be driven by fuel cell performance rather than price because compelling performance will create opportunities that entice early adopters into action. Understanding the performance of fuel cell systems is therefore vital to assessing their commercial prospects. The theoretical performance of fuel cell systems is widely understood and accepted. The key to understanding the actual performance and application potential of fuel cell systems is to acquire and test actual hardware. The saying "the devil is in the details" is nowhere more true, and testing fuel cell systems is the only way to obtain the detailed knowledge necessary to evaluate the value proposition. Lessons learned from installing, operating and maintaining a fuel cell system are invaluable for making critical decisions about purchasing or investing in fuel cell technology, and in making the most cost-effective, lowest risk decisions about target applications. As with all manufactured products, fuel cell manufacturer's specifications and product literature can't tell the whole story. Actual operations reveal, for example, how well the equipment holds up over time, how easy it is to fix, and how much assistance the user can expect from the manufacturer's technical support staff. In-house testing is ideal, but few organizations are set up and staffed to perform such tests. Many of those that are, cannot justify the dedicated commitment of resources to conduct a full-featured inhouse test and evaluation program. In-house testing often requires laboratory facilities, testing support equipment such as load banks, data acquisition systems, fuel handling equipment and hydrogen safety systems. Testers must also have and dedicate a skilled labor force capable of operating, maintaining and interpreting test results. The human resource and testing facility investments necessary to establish a capability to test multiple systems is significant. Once these investments are made, the single largest cost however can be the fuel cell equipment itself. Depending on the brand and size, stationary PEM fuel cell systems can today cost from a low of $3,000 per kW to upwards of $20,000 per kW and more. Testing equipment from multi-

Fuel Cell Magazine • December 2004 / January 2005

Research & Development

Module 3: Constant 1000 W

Module 4: Cycle for 2 hrs @ 500 W – 1 hr off

24 hr Snapshots 500 hrs run

Figure 1.

How Much Progress has been made by Fuel Cell Manufacturers? Since testing began at HARC, the program has discerned significant and measurable improvements in system performance and cost reduction. Manufacturer's are putting much more attention to the details and finish of their products, and to ensuring that systems meet the requirements of their intended applications. Nagging problems like deionized water usage, hydrogen consumption while in stand-by mode and unscheduled power interruptions are being minimized or eliminated. New products provide tangible performance enhancements, which provide reason for optimism that the technology will begin entering J32 J48C the market soon in Unit specific niche marFigure 2.

Volumetric Pow

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ple manufacturers or multiple generations of equipment from a single manufacturer can drive up technology acquisition costs quickly. To overcome the cost, capacity and infrastructure issues inhibiting their own in-house testing, a number of companies and organizations tracking developments among the fuel cell system manufacturers have banded together to create a fuel cell evaluation center at the Houston Advanced Research Center (HARC). HARC's fuel cell program provides end-users with practical operating information through high quality, comprehensive, technically-sound testing. Program participants receive periodic evaluations and technical reports, opportunities for hands-on learning in the laboratory, and an opportunity to meet twice each year to review data, meet with manufacturer representatives and discuss issues impacting the industry. The opportunity to interact with fuel cell manufacturers in the early stages of product development means that program offers a channel by which participants can even influence product features. Located in The Woodlands, Texas, HARC is a non-profit research organization looking to advance sustainable development in the Houston and Texas Gulf Coast region. In 2000, HARC began a sponsor-driven, industry consortium called the Center for Fuel Cell Research and Applications (CFCRA), which tests and evaluates commercially available and near commercially available fuel cell systems for technology consumers. Sponsors include early adopters, systems integrators, component suppliers, distributors and investors. Collaborative programs like CFCRA are cost-efficient because testing costs are spread evenly across all participants. For a small annual fee, participants can gain detailed information as if they were performing tests in-house. The CFCRA operates a well-equipped laboratory suitable for evaluating a wide variety of fuel cells, fuel reformers, hydrogen production systems and related equipment. Functional testing or so-called "blackbox" testing is performed on the fuel cell systems in accordance with the ASME PTC-50 specification. Functional testing ensures test results are comparable between manufacturers and satisfies developers concerned about potential compromises to their intellectual property. While functional testing can be used to deduce the performance of some sub-components from the overall system performance, the focus of the evaluations is to understand the operating characteristics of the system and its suitability for its intended applications. The heart of the CFCRA's evaluation is verification of the manufacturer's performance claims. System performance is monitored continually with "performance snapshots" taken every 500 hours of operation. The evaluation confirms the unit operates properly as suggested by the manufacturer and that the specifications are maintained over the specific environmental and operational conditions

Equipment Evaluations The CFCRA has tested or has plans to test fuel cells from Plug Power, Ballard Power Systems, ReliOn, Acumentrics, IdaTech and Nuvera. One of the first systems tested at HARC was a 5 kW system from Enable Fuel Cell, Inc., which was retrofitted with a HyRadix Alpha 4 natural gas reformer. HARC is currently testing the Ballard Nexa RM, the Plug Power GenCore, and the ReliOn Independence 1000 (Models J32 and J48C), all of which have received attention as a battery replacement option in UPS and backup power applications. The evaluation of the Ballard Nexa RM system is indicative of the type of testing performed at HARC. The test plan required four separate 1 kW modules, tested under a range of conditions (see Figure1). One unit, operated at 500 W continuous, acts as the control unit. The other three modules are used as experimental units to evaluate the impacts of continuous high output operation, excessive stop-start operation, and exposure to highly variable temperature and humidity conditions. To accomplish the test plan, the four modules are operated individually, but recomposed into a single 4 kW system every 500 hours to take a system snapshot, which involves a 24 hour test at various outputs.

Volumetric Power Density (W/m3)

Module 2: Constant 500 W control box

Gravimetric Power Density (W/kg)

Module 1: Outdoor operation @ constant 500 W

claimed by the manufacturer. System efficiency is measured as the system ages to assess system durability. Key variables that may be considered include intensive on-off cycles, continuous high power operation or temperature extremes. The CFCRA also evaluates the manufacturer by commenting on the ease of system installation, the quality of technical documentation, the manufacturer's responsiveness to problems and the effectiveness of the manufacturer's technical support. The wide range of metrics evaluated means that program sponsors get very nearly the full practical benefits and actual experience of owning and operating a laboratory full of different fuel cell systems.

18 | Research & Development kets. For example, over the last two years, ReliOn has made significant improvements in their Independence 1000 product line. A comparison of power density for the Model J32 (vintage late 2002) and the Model J48C (vintage early 2004) is shown in Figure 2. The green bar on the left in each set shows that the graviometric power density more than doubled, while the volumetric power density nearly doubled. To achieve these impressive results, ReliOn redesigned their power cartridge to improve output. As a result, the J48C model achieves the 1 kW rating with six cartridges, rather than the eight required in the J32. The upgrade was accomplished without increasing the size of the cartridges or the overall system. Plug Power has also made substantial progress in the last two years. Compared to the older SU-1 system (vintage 2001), their follow-on GenSys platform (vintage late 2003) is about 20 percent more efficient and offers significantly better stack durability. Their GenCore UPS system, announced in late 2003, has performed with and has a price tag under $3,000 per kW.

Conclusions HARC's fuel cell testing and evaluation provides industry sponsors with the real story of fuel cell technology performance. Much has been learned about how fuel cells will likely emerge in stationary applications, and much more will be learned as technology development continues. While fuel cells are not yet compelling options in most stationary applications, manufacturers are introduc-

ing equipment incorporating new features and better performance. Industry participants still have much to learn from the testing and demonstration of stationary fuel cell systems, especially as new models and configurations are introduced into the marketplace. HARC's unique practical experience with the exciting technologies reveals that: • commercial fuel cell products targeting UPS applications are appearing at cost and performance points attractive for further adoption; • PEM fuel cell systems with integrated fuel reformers targeting residential or small commercial primary power markets are still unattractive due to limited durability and relatively high costs; • low emissions, modularity and thermal energy can attract early adopters of fuel cell technology even at relatively high prices; and • demonstration programs generating quality test and evaluation data are essential elements for commercialization of fuel cells. The adoption of fuel cell systems in stationary applications is still an unfolding story and the journey from the laboratory to the marketplace has not yet been realized. As this emergent technology evolves and matures, actual operating experience and practical understanding are critical to making good decisions on their opportunity and use. Contact Dan Bullock, program manager with HARC at [email protected].

Reprinted from the December 2004/January 2005 issue of Fuel Cell magazine. ©2004 Webcom Communications Corp. 7355 E. Orchard Rd., Ste. 100, Greenwood Village, CO 80111 USA Phone 720-528-3770. Fax 720-528-3771. www.FuelCell-Magazine.com