DEVELOPMENT OF HIGH EFFICIENCY, SMALL SCALE HEAT ENGINE TECHNOLOGIES FOR POINT OF USE ELECTRICITY GENERATION SYSTEMS

The goal of the GENSETS program is to realize an affordable generator-engine system with 1 kW of electrical output, fuel energy content to electricity conversion efficiency exceeding 40%, long life, and low emissions. A system can be broken into 5 primary subsystems: (1) a chemical combiner or burner, (2) an engine, (3) an alternator, (4) a heat rejector, and (5) a controller. This work focuses on the implementation of a disruptive heat engine for subsystem (2), together with well-developed, widely available technologies for the remaining items, assembled to form a transformative technology for distributed small CHP. Specifically, this work will develop a new approach to a Stirling engine through the use of Sencera Energy’s flexure-based volume displacement devices, obviating the need for a piston and cylinder. The two major barriers for most Stirling designs are high overall production cost and difficulty with cost-effective transformation of engine power to useful electricity. The flexure concepts that have been thus far explored by Sencera provide the capability to change engine space volumes without the need for a precise sliding seal, allowing for higher compression ratios, lower engine losses, and lower production cost compared to existing Stirling technologies. The engine concept to be developed is a kinematic design with a rotational output, which allows the use of robust and mature off-the-shelf alternator technologies and associated controllers.