A THEORETICAL-STUDY OF A THERMOSIPHON SOLAR TURBINE

In this paper, we study the feasibility of generating power with very tall solar collectors and the thermosyphon effect. The vertical collec tors are heated by sunlight and open to the atmosphere at the top and bottom, resulting in rapid air flows through the collectors. This movi ng air can then be used to drive turbines for generating electric powe r, We find that the efficiency of such a device increases with its hei ght, and that the length of the unit does not affect efficiency. We al so find that, to achieve an acceptable level of efficiency, the device must be extremely tall; we calculate a conversion efficiency (percent age of the solar radiation received that can be converted to mechanica l power) of 0.2% for collectors 100 meters in height, and 1.6% for 500 -meter tall collectors. We calculate that a 500-meter tall collector, 160 meters in length, could generate about 1 MWatt of power if 800 W/m (2) of solar radiation are absorbed by the collector. The efficiency o f the collector also depends on the number and size of the turbines-th ere is an optimal combination of these for a given solar intensity, co llector length, and collector height. We find that the solar intensity has little effect upon efficiency power generated is directly proport ional to solar intensity.