Harnessing the Sun 



By W'aldeniar Kaempffert 



In the Sun Power Plant which Mr. Shuman erected at Maadi, near Cairo, Egypt, steam 

 is generated by parabolic mirrors set in a light steel framework so as to throw the sun's 

 rays upon a long trough through which water flows in a shallow stream. Thus steam is 

 generated on the same principle applied in a greenhouse to prevent plants from freezing 



IF a boy can burn his name on a wooden 

 bench with nothing but the aid of a 

 convex lens and the sun's rays, why 

 is it not possible to make the sun boil 

 water, generate steam, and drive an 

 engine? It seems absurd to burn coal 

 costing from three dollars to thirty 

 dollars a ton, depending upon your lati- 

 tude and longitude, when the earth is 

 deluged with heat. 



The thought of using solar energy for 

 generating power has occurred to many 

 an engineer. John Kricsson, the in- 

 ventor of the "Monitor," made more 

 than one attempt to harness the sun. 

 In his mind's eye he saw a desert tract 

 nine thousand miles long and one hun- 

 dred miles wide, extending from the Nor- 

 thern coast of Africa as far as Mongolia, 

 and great arid regions running from the 

 southwestern part of the United Slates 

 through Central America and along the 

 coast of South America for a length of a 



thousand miles, animated with millions 

 of throbbing engines deriving their 

 power from the sun. On a rainless strip 

 eight thousand miles long and one mile 

 wide enough solar heat is wasted, he 

 figured, to drive twenty-two million, 

 three hundred thousand solar engines of 

 one hundred horse-power each, nine 

 hours a day. Why, he asked, why 

 should not upper Egypt derive signal 

 advantage from its fortunate desert 

 location and attain a high social position 

 because of its perpetual sunshine? 



For thirteen years Ericsson worked 

 with diligence born of optimism. Be- 

 tween 1865 and 1878 he built no less 

 than seven solar motors. Instead of a 

 lens he employed mirrors, which were 

 fastened on a movable frame and which 

 concentrated the sun's rays on a boiler, 

 when he was flriving his engine by 

 steam, and on an air-chamber, when he 

 employed a hot-air engine. Although he 



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