Design and Characterizations of Solar Steam Engine
In this paper a conceptual design of solar steam dish concentrated ( 2 m ) area was used .With cylindrical receiver as a solar boiler and two axis tracking system .the experimental were conductance from 80-150 °C under a mean solar flux of (250 -780 W/m) concentration product analysis of this innovative solar boiler applied drive to steam engine. We have found that overall efficiency of the conversion from direct solar irradiation energy to
Economic Potential of Solar Thermal Power Plants With Direct Steam Generation Compared With HTF Plants
The direct steam generation (DSG) in parabolic trough collectors is a promising option to improve the mature parabolic trough solar thermal power plant technology of the solar energy generating systems (SEGS) ; in California. According to previous studies (Langenkamp, 1998, "Revised LEC Projections and Discussion of Different DSG Benefits, " Technical Report No. DISS-SC-QA-02, Almeria, Spain; Price, et al., 2002, "Advances in Parabolic Trough Solar Power Technology, " ASME J. Sol. Energy Eng., 124(2), pp. 109-125; Zarza, E., 2002, "DISS Phase II Final Report, " Technical Report EU Contract No. JOR3-CT98-0277, Almeria, Spain], the cost reduction in the DSG process compared with the SEGS technology is expected to be 8-25%. All these studies were more or less preliminary since they lacked detailed information on the design of collector fields, absorber tubes required for steam temperatures higher than 400°C, and power blocks adapted to the specific needs of the direct steam generation. Power blocks and collector fields were designed for four different capacities (5 MW el , 10 MW el , 50 MW el , and 100 MW el ) and different live steam parameters. The live steam temperature was varied between saturation temperature and 500°C and live steam pressures of 40 bars, 64 bars, and 100 bars were investigated. To assess the different cases, detailed yield analyses of the overall system were performed using hourly data for the direct normal irradiation and the ambient temperature for typical years. Based on these results, the levelized costs of electricity were determined for all cases and compared with a reference system using synthetic oil as heat transfer fluid. This paper focuses on two main project findings. First, the 50 MW el DSG system parameter comparisons are presented. Second, the detailed comparison between a DSG and a SEGS-like 100 MW el system is given. The main result of the investigation is that the benefit of the DSG process depends on the project site and can reach an 11 % reduction in the levelized electricity cost.
Thermofluidynamic Model and Comparative Analysis of Parabolic Trough Collectors Using Oil, Water/Steam, or Molten Salt as Heat Transfer Fluids
This paper describes the development and use of a thermofluidynamic model for parabolic trough collectors, specifically suited for carrying out systematic calculations on different design options. The model is based on detailed energy balances, and it has been applied to evaluate collector thermal performances with different working fluids: oil, molten salt, or water/steam. For each heat transfer fluid technology, four parameters have been analyzed: collector length, absorber tube diameter, working temperature, and pressure. The influence of these factors has been studied from the point of view of heat loss, pressure drop, energy and exergy efficiencies. Exergy is considered the suitable magnitude to guide any optimization process in this field, because it accounts for all relevant energy gains and losses, characterized by their corresponding temperature and pressure. Preliminary conclusions point out that direct steam generation is more efficient than oil and molten salt systems.