A Miniature Power- Plant for the Home 



All the essential elements of a great commercial 

 supply plant are incorporated in simplified form 



A COMPLETE power-plant supplying 

 a home with all the electricity it 

 needs is in reality a miniature power- 

 house hke that used to supply electricity to 

 thousands of homes. It must contain all 

 the essential elements of such a'power-house 

 but on a smaller and simplified scale. 



Still, a gasoline-engine and a dynamo 

 are not simple things. Formerly, only a 

 skilled electrician and mechanic was able 

 to run his own plant without trouble. With 

 the further development of the individual 

 electric-plant, however, it has finally been 

 made practically automatic in operation 

 and so simple that a child can operate it. 



One of the first things simplified was the 

 gas-engine. It is now automatically oiled. 

 Because it has a self-starter, it is started 

 bv the mere , 



closing of a °''"°^^ 

 switch. The 

 next improve- 

 ment was the 

 combining of 

 the engine and 

 dynamo into 

 one apparatus. 

 Formerly they 

 were separate 

 machines con- 

 nected by a 

 long belt. Now 

 they are 

 mounted on 

 the same shaft. 

 Lastly stor- 

 age-batteries 

 are now used, 

 which not only 



enable a man to run his engine-dynamo 

 set during the odd times he is at lei- 

 sure, but have greatly reduced the 

 cost of producing the electricity. 



The storage -batteries serve the 

 purpose of storing the electricity 

 until the time when it will be wanted, 

 in much the same way as a reservoir 

 -tores water. After they have been 

 filled, the batteries will hold enough 

 electricity to last for four or five days 

 of service. When they are empty, it is 

 necessary only to start up the engine 

 and dynamo again. The engine drives 

 the dynamo and when it revolves, just 



as when the great dynamos oi a large power- 

 house revolve, electricity is produced. The 

 dynamo then feeds the electricity into the 

 storage-batteries to be again stored until 

 wanted. It has been made easy to tell 

 when the batteries are empty ; for at such a 

 time an instrument on the switch-board 

 which is mounted on the top of the dynamo, 

 points to the word "empty." 



When running normally, the plant can 

 light fifteen sixteen-candlepower lamps, or 

 it can run two small motors of one-sixth 

 horsepower each. It can do this continu- 

 ously for eight hours. If it is desired to use 

 them longer, it is necessary only to close 

 the switch of the self-starter of the engine- 

 dynamo set. The plant can also be used to 

 light thirty-two lamps, or fifteen lamps and 

 two motors, by start- 

 ing up the engine- 

 dynamo set and run- 

 ning it continuously. 

 The cost of gaso- 

 line for the engine 

 is only twenty- five 

 cents a day. When 

 natural-gas can be 

 used in the engine, 

 this cost is still 

 further reduced 

 to eight cents a day. 



Oil-less bearing 



Above: Cross-section of the simplified engine-dynamc 

 se^ Below : The set complete, with the batteries 



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