Next Generation SOFC
SECA - Solid State Energy Conversion Alliance
Description
Mindful of the need for product development, performance improvement and, above all, cost reduction, Siemens Power Generation has conducted research in new materials, improved manufacturing processes and HPD seal-less planar cell designs. A number of these seal-less planar high power density (HPD) cell prototypes have been fabricated, and tests are being conducted to evaluate the candidate cell designs.
Candidate seal-less planar cell designs under evaluation
Extensive work on a 5 kW prototype system that operates on natural gas also has been carried out by Siemens Power Generation's system sub-contractor Fuel Cell Technologies Ltd. A number of 5 kW systems, based on Siemens Power Generation's tubular cells, have already been fabricated and are presently being tested.
A prototype 5kW SOFC system under test in collaboration with Fuel Cell Technologies Ltd.
In August 2002, under the US Department of Energy's (DOE) Solid State Energy Conversion Alliance (SECA) program, Siemens Power Generation entered into an $80 million cooperative agreement with DOE's National Energy Technology Laboratory to develop low-cost Solid Oxide Fuel Cell (SOFC) power systems for residential, automotive and military applications. Under the agreement, entitled "Small-scale, Low-cost SOFC Systems," Siemens Power Generation will develop a revolutionary new seal-less planar SOFC that takes advantage of the company's pioneering work and leadership position with SOFC systems.
A seal-less planar HPD cell design under development by Siemens Power Generation.
The program will be executed in three phases over a ten-year period, and at the end of each phase a prototype SOFC system in the 3-10 kW range will be tested for one or more of the targeted applications. Specific cost targets for each phase will be addressed with the ultimate program target being $ 400/kW in high volume production.
Siemens Power Generation has assembled a technical team of key technology development partners that includes Fuel Cell Technologies Ltd. (FCT) of Kingston, Ontario, for system development, and Blasch Precision Ceramics of Albany, New York, for module component development. FCT brings extensive experience with small fuel cell systems in a variety of applications, and Blasch will contribute its broad experience with high temperature component design and manufacture. Participation by a number of other companies in a customer/market team, including Lennox Industries, the Trane Company, Ford Motor Company, Eaton Corporation, and Newport News, is also planned for later stages of system design and testing.
Technical Details
The high efficiency and environmental friendliness of solid oxide fuel cells already have been well established by Siemens Power Generation for stationary base-load applications. Product validation and cost reduction are now primary objectives for stationary market applications, with further cost and performance improvements needed for other mass market applications, such as military and transportation. The fundamental objective of this SECA program is to develop a revolutionary SOFC that can be manufactured in large volume for a variety of applications at a lower cost than current fuel cell components. In order to achieve this objective, aggressive research into new materials and capabilities is planned.
Current capabilities and characteristics of SOFCs can be compared to the objectives of the SECA program, as follows:
Current SOFC Characteristics
| SECA Objectives
|
High operating temperature
| Wider operating temperature range
|
Intolerant of sulfur in fuels
| Sulfur-tolerant anode
|
Internal or external fuel reformation
| Capability for on-cell reformation
|
Reliance on natural gas or other limited fuels
| Viable fuel processors for common liquid fuels (diesel, kerosene)
|
Limited thermal cycling, load follow capability
| Improved capabilities
|
Low system power density
| Higher power density cells, parts and weight reduction
|
Under Siemens Power Generation's SECA program these objectives are being addressed with the expectation that small-scale SOFC products can be started quickly, cycled in and out of operation as needed, and operated at high efficiency on natural gas or available liquid fuels, such as kerosene or diesel.