Stationary Power Systems

Timothy Armstrong (Primary Contact), Dane Wilson, Lynn Klett 

DOE Technology Development Manager Nancy Garland 202-586-5673, fax (202) 586-9811, e-mail Nancy.Garland ee.doe.gov 

A collaborative laboratory effort between Oakridge National Laboratory and Los Alamos National Laboratory has recently been undertaken to evaluate the alkaline fuel cell literature and develop a research and development program plan. To date, the team evaluated the literature and drafted a review of the state-of-the-art. Based on this and input from industrial participants, a research plan is being 

2 Development of Advanced, Low-Cost PEM Fuel Cell Stack and System Design for Operation on Reformate 

Built and operated a 3-kWj,et fuel cell power plant with integrated natural gas reformer. 

---

The fuel cell itself liberates heat that can be utilized for space heating or hot water. The reference article did not list any operating conditions of the fuel cell or of the cycle. The PEFC is assumed to operate at roughly 80°C. Another recent article (49) published by Ballard shows numerous test results that were performed at 3 to 4 atmospheres where fuel utilizations of 75 to 85% have been achieved. Performance levels for an air fed PEFC are now in the range of 180 to 250 mW/cm. Ballard Power Systems has performed field trials of 250 kW systems with select utility partners. Commercial production of stationary power systems is anticipated for the year 2002. Similarly sized transportation cycles also are anticipated for commercial production in the same year. 

Aluminum Batteries Chemical Thermodynamics Electrochemistry Fuel Cells, Applications in Stationary Power Systems Kinetics (Chemistry) Transportation Applications for Fuel Cells... 

The focus of most of this report and this chapter is on light-duty passenger vehicles, the largest segment of the vehicle market. Stationary power systems to produce electric power from hydrogen may be an important part of a possible future H2 energy system, both in a transition to a hydrogen economy and also in the steady state. The committee did not do an extensive analysis of the future stationary electric power system in the United States and the role that H2 may play, but the section below entitled Stationary Power Utilities and Residential Uses delineates some of the developments and opportunities in fuel cells and turbines for stationary power. 

Ballard supplies stacks to its end-use partners to gain experience with vehicle and stationary power systems. The stacks, and their associated systems, are, and must be, tested in a breadth of operational exigencies. 

Electrical generators capable of high conversion efficiencies and extremely low exhaust emissions will no doubt power advanced hybrid vehicles and stationary power systems. Fuel cells are generally considered to be ideal devices for these applications... 

At a very early R D level is the use of coal gasification integrated in a high-temperature fiiel cell as a stationary power system (see section 7.2.2.3.). 

PEMFCs are characterized by low operative temperature (80-100°C), high current density, compactness, fast start-up and suitability for discontinuous operation [21]. These features make PEMFCs the most promising and attractive candidate for a wide variety of power applications ranging from portable/micropower and transport to large-scale stationary power systems for buildings and distributed generation [22], as shown in Fig. 2.6. 

Applications Transportation, Space, Military, Energy storage systems Combine heat and power for decentralized stationary power systems Combine heat and power for stationary decentralized systems and for transportation (trains, boats,...) ... 

Due to their excellent power density and good energy conversion efficiency, polymer electrolyte firel cells (PEFCs) are promising candidates for transportation, as well as portable and stationary power systems [63]. In recent years, extensive research has been done on the oxygen reduction reaction on platinum at solid polymer electrolyte interfaces [64, 65]. Nafion is often used as the electrolyte in low-temperature fuel cell systems, as it enables the porous catalyzed carbon to be integrated into the electrolyte by extending the three-dimensional reaction zone [66, 67]. 

The HFP focuses on the acceleration and development for cost reduction necessary to competitively market fuel cells for transportation, stationary, and portable power applications. Their Hyways Project Roadmap aims for a mass market rollout by 2020 for European class vehicles with efficiencies of at least 40% on the New European Drive Cycle (NEDC) at a cost of 100 Euros kW and lifetimes of 5000 h for automobiles and 10,000 h for buses. The goals for stationary power systems mainly target residential power systems which the HFP hopes to see tangible market penetration by 2020. By 2009-2012, these systems are expected to maintain 34-40% electrical efficiency, a total fuel efficiency of 80%, >12,000 h of operation and cost less than 6000 Euro per system stack (Borup et al., 2007). 

If we were to consider building our example system stationary power system we would now progress to the stage of detailed engineering design. This would address issues such as start-up and shutdown. For example, we may need to ask the following questions ... 

There are a host of fuel cell applications from portable devices to transportation to large-scale stationary power systems. The fuel cells are being used as... 

Electron Transfer Reactions Fuel Cells, Applications IN Stationary Power Systems... 

Because both electricity and heat are desirable and useful products of SOFC operation, the best applications are those which use both, for example residential combined heat and power, auxiliary power supplies on vehicles, and stationary power generation from coal which needs heat for gasification. A residential SOFC system can use this heat to produce hot water, as currently achieved with simple heat exchangers. In a vehicle the heat can be used to keep the driver warm. A stationary power system can use the hot gas output from the SOFC to gasify coal, or to drive a heat engine such as a Stirling engine or a gas turbine motor. 

S.K. Mazumder and R.K. Burra, Fuel cell power conditioner for stationary power system towards optimal design from reliability, efficiency and cost standpoint . Keynote Lecture, ASME Third International Conference on Fuel Cell Science, Engineering and Technology, FUELCELL2005-74178, May 23-25, 2005. 

---