NASA SBIR 2005 Solicitation


SUBTOPIC TITLE:Power Generation & Transmission
PROPOSAL TITLE:High Specific Power Multiple-Cylinder Alpha Free-Piston Stirling Engine

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
Sunpower, Inc.
182 Mill Street
Athens, OH 45701-2627
(740) 594-2221

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Seon-Young   Kim
6773 Beechwood Dr.
Athens, OH  45701-2627
(740) 592-0420

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
The proposed effort will result in a design of a 30 kWe dual opposed alpha free-piston Stirling engine power conversion system for space applications, and provide proof of concept by the operation of a practical alpha engine. The stepped piston three-cylinder alpha FPSE has shown the highest efficiency and excellent specific power among various engines studied in Phase I. In addition, the three phase electric output of a three-cylinder machine is naturally better in the system context. Thus a high efficiency 15 kWe stepped three-cylinder alpha FPSE will be designed for a 30 kWe dual opposed operation by having two engines connected for perfect balancing in all harmonics. The program minimizes the development risks by combining proven technologies of Sunpower and Global Cooling Manufacturing Inc. (GCM). GCM has achieved the successful operation of a four-cylinder alpha free-piston Stirling cooler.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
The resulting convertor will give spacecraft designers the option of utilizing a 1) compact, low mass, and highly efficient power supply, 2) a power supply module that can be clustered together to provide higher power levels, 3) a power supply which can be adapted to both space and planetary atmospheres via simple changes to the gas management system with no impact on the operation of the critical dynamic components inside the convertor, and 4) a controller design philosophy that allows the system to be easily adapted to varying mission requirements. Such a system is extensible to several areas of NASA's power generation needs including electric propulsion, robotic rovers, and backup power supplies for human surface expeditions.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
In addition to the space applications which this proposal addresses directly, there is a significant potential market for commercial power generation, particularly in light of increasing attention to the environmental cost of fuel consumption and the new stringent fuel emissions regulations in some areas of the world. Sunpower licensee MicroGen, for example, has determined a substantial European and worldwide market for household cogeneration devices. Additionally there are numerous opportunities for remote and mobile power generation applications, including the marine market, auxiliary power markets, remote power generation, standby emergency power generation, peaking generation, truck-mounted power, power for oil and gas fields and other exploratory and off-grid sites.

NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.

Nuclear Conversion
Power Management and Distribution
Renewable Energy
Thermodynamic Conversion

Form Printed on 07-25-06 17:04