Fuel cells turbines

Leo, A.J., Ghezel-Ayagh, H., and Sanderson, R., Ultra High Efficiency Hybrid Direct Fuel Cell/Turbine Power Plant, ASME 2000-GT-0552, October-November 1999... 

Advanced power generation cycles that combine high-temper-ature fuel cells and gas turbines, reciprocating engines, or another fuel cell are the hybrid power plants of the future. As noted, these conceptual systems have the potential to achieve efficiencies greater than 70% and projected to be commercially ready by the year 2010 or sooner. The hybrid fuel cell/turbine (FC/T) power plant will combine a high-temperature, conventional molten carbonate fuel cell or a solid oxide... 

There can be many different cycle configurations for the hybrid fuel cell/turbine plant. In the topping mode described above, the fuel cell serves as the combustor for the gas turbine, while the gas turbine is the balance of plant for the fuel cell, with some generation. In the bottoming mode, the fuel cell uses the gas turbine exhaust as air supply, while the gas turbine is the balance of plant. In indirect systems, high-temperature heat exchangers are used. 

The benefits and feasibility of hybrid systems have been established with conceptual studies and small-scale demonstrations fueled with natural gas. If large-scale, greater than 100-MW, fuel cell/turbine hybrid systems are to become a reality a reduction in fuel cell costs and scalability to larger units is required. The SECA program demonstrated 3 to 10 kW SOFC systems with costs of less than 800/kW in 2005. 

FCE plans to demonstrate a molten carbonate fuel cell/turbine hybrid system in late 2000. The balance of plant equipment employed in the 250 kilowatt test at ERC s facility will be modified to accommodate a fuel cell and a gas turbine. The turbine is to be powered by waste heat from the fuel cell. The goal of the test is to demonstrate that the hybrid system will realize high efficiencies. This activity is a part of the U.S. DOE Office of Fossil Energy Vision 21 Program. 

The combination of the fuel cell and turbine operates by using the rejected thermal energy and residual fuel from a fuel cell to drive the gas turbine. The fuel cell exhaust gases are mixed and burned, raising the turbine inlet temperature while replacing the conventional combustor of the gas turbine. Use of a recuperator, a metallic gas-to-gas heat exchanger, transfers heat from the gas turbine exhaust to the fuel and air used in the fuel cell. Figure 9-23 illustrates an example of a proposed fuel cell/turbine system. 

There can be many different cycle configurations for the hybrid fuel cell/ turbine plant. In the topping mode described above, the fuel cell serves as the combustor for the gas turbine while the... 

In March of 1999, FCE, of Danbury, CT, with Allison Engine Company, Indianapolis, IN, and Capstone Turbine Corp., Woodland Hills, CA. was awarded a project under the Vision 21 program to create a fuel cell/turbine system that provides efficiencies and emissions targets that meet or exceed stringent Vision 21 goals. The 3-year program will include four steps ... 

One method proposed for estimating the cost of fuel cell power plants is to calculate distributive (bulk) costs as a function of the equipment cost using established factors based on conventional generating technologies. When applied in such a way as to compensate for the differences associated with a fuel cell plant, this approach can yield reasonable results. NETL has elected, based on the international prominence of the Association for the Advancement of Cost Engineering (AACE), to utilize this approach in estimating the costs for fuel cell/turbine power plant systems currently under study. 

Smith T.P., Haynes C.L., Wepfer W.J., Liese E.A., Tucker D. (2006) Hardware based simulation of a fuel cell turbine hybrid response to imposed fuel cell load transients. In Proceedings of the ASME International Mechanical Engineering Conference and Exhibition, Chicago, IL, IMECE2006-13978. 

As a fuel producer for highly efficient fuel cells by hydrogen or perhaps in the future, hydrogen turbines and fuel cell-turbine hybrid systems. 

Siemens Westinghouse is advanced in its pursuit of gas turbine integration. High-temperature depleted air and unused fuel from the fuel cell cannot be discarded, and are best used in a gas turbine, as outlined in Baozhen Li etal. (2001), the Siemens patent for a Single Module Pressurised Fuel Cell Turbine Generator System (pp. 974-979). The effect... 

George R A etal, 2001, Single Module Pressurised Fuel Cell Turbine Generator System. US Patent (pending), WO 01/06589 Al. 

Figure 4. Fuel cell/ turbine hybrid system.

In the fuel cell/turbine hybrid power plant the fuel cell does not need to operate at the turbine pressure, instead it operates at the preferred ambient pressure and its independent of gas turbine cycle pressure ratio. The system works efficiently with a wide range of turbine compression ratio. This allows taking a system developed for integration at the multi-MW... 

A plant eonsisting of a load is fed from the fuel cell/ turbine hybrid system. The seleeted system eomprises a 250 kW fuel eell and a 30 kW gas microturbine. The plant and the fuel cell/ microturbine system are modeled using MATLAB . 

Stemfeld G., Maru H.C., Sanderson R.A., 1996. High efficiency carbonate fuel cell/turbine hybrid power eycles, in Second Workshop on very high efficiency fuel cell/advanced turbine power cycles. In Fuel Cells Conference. 

Figure 32.8 Exergy flow diagram for a power-optimized lOkWei HT-PEFC system based on C12H26 as a model fuel for kerosene designed as a fuel cell/turbine hybrid.

Power conversion architectures for a fuel cell turbine hybrid interfaced to local utility... 

Power Conversion Architecture for a Fuel Cell Turbine Hybrid Interfaced With a Local Utility... 

Figure 8-21 Power conditioning unit for the 250kW fuel cell turbine hybrid system...

Figure 8-22 Alternative power conditioning unit for the fuel cell turbine hybrid...

H.G. Ayagh, J.M. Daly, et al. Critical Components for Direct Fuel Cell/Turbine Ultra-Efficiency system . Presented at Turbine Power Systems Conference and Conditioning Monitoring Workshop, Galveston, TX, Feb 2002. Authors affiliation Fuel Cell Energy Inc. Danbury, CT. 

DOE Techline Press Release, Department of Energy Announces World s First Hybrid Fuel Cell-Turbine, April 2000. 

Rolls Royce is working on developing a 1 MW fuel cell/turbine hybrid system, with a demonstration product date of 2008. The system, of which an artist s impression is shown in Figure 6.8, has four 250kW units linked together. 

Aim - by 2015 to develop and demonstrate the critical high-risk technology advancements that will permit the US industry to establish commercial availability of advanced, low-cost, ultra-high-efficiency, fuel flexible, integrated fuel cell/turbine hybrid systems for synfuel and hydrogen-based plants . 

Figure 7.2 Efficiency limits for a heat engine, a hydrogen fuel cell, and a fuel cell/turbine combined cycle. For the heat engine and the combined cycle, the lower temperature is 100°C. The fuel cell efficiencies are referred to as the higher heating value.

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