Commercialization Of Dish-stirling Solar Terrestrial Systems

The application of Stirling engines to solar terrestrial applications has received an increasing amount of interest over the past few years, stimulated by concern about limited energy resources and preservation of the environment. A Dish-Stirling Commercialization Workshop was sponsored by the Electric Power Research Institute (EPRI) during May, 1989 to evaluate the prospects for this application. This paper describes the approach of Westinghouse Electric Corporation and Stirling Technology Company (STC) for commercialization of dish-Stirling solar terrestrial systems. The requirements for practical terrestrial power systems, both technical and economic, are described. Solar energy availability, with seasonal and regional variations, is discussed. The advantages and disadvantages of hybrid operation are listed. The two systems described use either a 25 kW free-piston Stirling hydraulic engine or a 5 kW kinematic Stirling engine. Both engines feature long-life characteristics that result from the use of Welded metal bellows as hermetic seals between the working gas and the crankcase fluid. The advantages of the systems, the state of the technology and the challenges that remain are discussed. Technology transfer between solar terrestrial Stirling applications and other Stirling applications is predicted to be important and synergistic. In conclusion, the requirements for dish-Stirling commercialization are described.