A low-voltage plant for a small house capable of supplying twenty-four 16-candle power bulbs, showing the simplicity of the complete plant 
SERVICE SUPPLIED FOR THE FULL TWENTY-FOUR HOURS WITH THE GENERATOR WORKING ONLY 
A FRACTION OF THAT TIME—HOW THE ELECTRICITY IS STORED UP—THE COSTS OF A PLANT 
J. F. Springer 
E LECTRIC lighting can be provided nowadays at reasonable 
expense for moderate-sized bouses, and that service may 
be supplied for the full twenty-four hours without requiring the 
operation of the generating apparatus for more than a fraction 
of that time. Perfection of service and economy of operation 
are now combined. Country and city are alike the beneficiaries 
of modern progress in lighting methods. 
Electric lighting can hardly be said to be a cheap system ; but, 
despite its cost, it is to¬ 
day the favorite. There 
are many instances 
where electric lighting 
is secured through the 
generation of current by 
private plants located on 
the premises of the con¬ 
sumer. Except, how¬ 
ever, where the current 
is consumed in lighting 
a hotel, an apartment 
house or group of such 
houses, the inconven¬ 
ience in operating the 
equipment has probably 
hindered the introduc¬ 
tion of electric lighting. 
Now, it is possible to 
have an electric lighting 
system of such a charac¬ 
ter that it is not neces¬ 
sary to operate a dyna¬ 
mo simultaneously with 
the generation of the 
light. With the electric 
storage battery, the cur¬ 
rent may in effect be 
stored up to be used 
when the dynamo is quiet. The storage battery is the equivalent 
of a tank full of electricity, but it does not afford a perpetual sup¬ 
ply without being itself re-supplied. During the day, at one’s 
convenience, the storage battery is charged by operating a dyna¬ 
mo. The battery then becomes a source of electricity, which 
may be drawn upon at any time desired. With the best batteries 
no attention is required during the period when the current is 
being consumed. In the practical operation of a small electric 
lighting system, this feature becomes of very great importance. 
A storage-battery system consists—apart from the wiring and 
fixtures—of four elements: a gasoline engine, or other source of 
mechanical energy, which is employed to operate the second ele¬ 
ment—the dynamo. The function of the dynamo is to generate 
an electric current, which, in turn, is employed to charge a 
storage battery. Finally, the fourth element is a switchboard, 
whose function is to provide a means of controlling the electric 
operations. 
With an equipment of 
this character we have 
not only a means of 
lighting the house, but 
also a source of power 
applicable to other uses. 
The gasoline engine may 
he disconnected a n d 
operated to run various 
mechanical devices. If 
the mechanical devices 
are too far away or too 
scattered to permit the 
use of the gasoline en¬ 
gine as a source of 
power, then we may 
operate them by an elec¬ 
tric current. Thus, cur¬ 
rent may be obtained by 
operating the gasoline 
engine and the dynamo 
in conjunction. Indeed, 
we may connect up the 
electric light wires and 
operate the lights in the 
same way. Then, we 
may use the whole plant 
and “store up” elec¬ 
tricity in the storage battery, which may be used to supply cur¬ 
rent for the lighting or the operation of mechanical devices. 
These several alternatives are not equally economical in respect 
to the cost of operation. For example, we can run a pump for 
less money by connecting it up to the gasoline engine than by 
using current from the dynamo or the storage battery. Again, 
we can operate it more economically by using current from the 
(Continued on page 56) 
The storage battery room on the Harry Payne Whitney estate on Long Island, showing batteries 
in position. This is the other extreme from the plant shown above 
39 
