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Williams, A. N.

Publications and source records attributed to Williams, A. N..

Proximity operations concept design study, task 6

The feasibility of using optical technology to perform the mission of the proximity operations communications subsystem on Space Station Freedom was determined. Proximity operations mission requirements are determined and the relationship to the overall operational environment of the space station is defined. From this information, the design requirements of the communication subsystem are derived. Based on these requirements, a preliminary design is developed and the feasibility of implementation determined. To support the Orbital Maneuvering Vehicle and National Space Transportation System, the optical system development is straightforward. The requirements on extra-vehicular activity are such as to allow large fields of uncertainty, thus exacerbating the acquisition problem; however, an approach is given that could mitigate this problem. In general, it is found that such a system could indeed perform the proximity operations mission requirement, with some development required to support extra-vehicular activity.

Williams, A. N.

Heat and electricity from the Sun using parabolic dish collector systems

Point focus distributed receiver solar thermal technology for the production of electric power and of industrial process heat is addressed. The thermal power systems project which emphasizes the development of cost effective systems which will accelerate the commercialization and industrialization of plants up to 10 MWe, using parabolic dish collectors is described. The projected size of the isolated load market in the 1990-2000 time period is 300 to 1000 MW/year. Although this market is small in comparison to the grid connected utility market, it is indicated that by assuming only a 20 percent market penetration, up to 10,000 power modules per year would be required to meet this need. At a production rate of 25,000 units/year and assuming no energy storage, levelized bus bar energy costs of 75 mills/kWeh are projected. These numbers are based on what is believed to be a conservative estimate regarding engine-generator conversion efficiency (40 percent) for the 1990 time period. With a more optimistic estimate of efficiency (i.e., 45 percent), the bus bar cost decreases to about 67 mills/kWeh. At very large production rates (400,000 modules/years), the costs decrease to 58 mills/kWeh. Finally, the present status of the technology development effort is discussed.

Truscello, V. C.

The JPL parabolic dish project

The parabolic dish solar collector is a highly versatile concentrating collector system that can produce heat for many thermal processes and electricity by coupling the collector to a suitable heat engine. This paper discusses a project for the development of these collector systems and summarizes contracts with industry for developing the dish subsystems which include concentrator, receiver, and heat engine. An early market for dishes is the dispersed small community market which depends heavily on oil to operate diesel or steam turbine plants in order to generate electricity. The present contracts with industry for conducting engineering experiments using the developed dish hardware to demonstrate the technology in these early opportunity markets is also discussed.

Truscello, V. C.

Heat and electricity from the sun using parabolic dish collector systems

The paper investigates point focus distributed receiver (PFDR) solar thermal technology for the production of electric power and of industrial process heat. Attention is given to a thermal systems project conducted by JPL under DOE sponsorship. It is reported that project emphasis is on the development of cost-effective systems which will accelerate the commercialization and industrialization of plants up to 10 MWe, using parabolic dish collectors. Also discussed are the characteristics of PFDR systems, the cost targets for major systems hardware, and markets for this technology. Finally, the present system status of the technology development effort is discussed.

Truscello, V. C.