Evening public ledger. [volume] (Philadelphia [Pa.]) 1914-1942, 1919-07-26
Making the Lightning Safe for
Democracy

7 DOUBT whether the ingenuity of men in
the management of their complex affairs
has ever been brought to higher pitch than
in the regulation of great city's daily con-
sumption of electric current.
| went recently to visit the Office of the
Load Dispatcher of The Philadelphia Flee
trio CompanN at Tenth and Chestnut. From
one switchboard in quiet room the greater
part of the electric energy used in the entire
region of Philadelphia and suburbs is con-
trolled by two men. The scientific details of
their task are little beyond the grasp of
the layman, but the general principles are
simple enough and are of interest to every
citizen who makes any use of electricity in
his daily affars-Pither for transportation,
commercial power or in the home. If you
ride into town on the electrified sections of
the L. Il. r., if you board trolley car, If
you use a telephone or turn on a bulb or an
electric vacuum cleaner in your home. every
unit of current that helps you on your way
is recorded on the Load Dispatcher's board.
1t is like the staff headquarters of an army
the great army of electricity--and Mr.. Black,
the chief Load Dispatcher, is the Foch of
the system. No piece of generating or dis
tributing apparatus in the district can be
used or laid off except under his orders.
L curved screen twenty feet long with over
a hundred panels. which give diagram of
every generating station and substation in
the Philadelphia district. On this great
chart You will see multitude of small green
lights. each one representing apparatus in
normal operation. When any unit is dead
it's light is unlit. Here and there are small
red lights to indicate units that are blocked
out for some reason perhaps for repairs.
The desk is in direct telephone communca-
ton with every source of power in the sys-
tenn As you watch the switchboard, little
white lights fash up. These are the outposts
of the army calling in to headquarters to
report conditions, perhaps to announce II
thunderstorm on its way toward the city
from Tacony or Willow Grove or Chester,
and to ask instructions in case sCme rcdistri-
button of current is necessary.
TNHE first thing to get clearly in mind is
l. that the citys current requirements fuc
tuate all day long. requiring inccssant dis
tributOn of the load" over its various
channels.
This fluctuation not only takes place all
day long but from day to day, according to
| the season of the year, the amount of day
| light and the industrial requirements of the
| day. 1t is obvious that the problem of sup
| plying current IS quite dlHerent on q hONuay
| and on working day it is quite different
| on day in December and day in July.
| And as electrical apparatus is subject to
| many conditions not humanity cOntrollable,
the problem of the Load Dispatcher is to be
| prepared for every possible emergency, so
that II any breakdown occurs in a general
ing station or out along the lines of cable
! or overhead transmission, other units Of
power can be switched on to keep the wheels
turning without more than few minutes (or
! even scconds) of delay. l was shown fasc-
mating series of cards illustrating the varia
| ton of Phadephia's consumption of cur
rent during a whole year. a glance at this
stack of graph cards gives map of the city's
industrial and social life.
NNAKE, for instance, a day in midwinter
l. when the city's electrical needs are Mt
their highest. Beginning at midnight one
| sees the line of current consumption dropping
rapidly as lights are going of all over the
city. reyelers are making their way home
ward from theatres and cafes. The graph
drops steeply from midnight until 2 q. m
and reaches its lowest point from to f.
Shortly after it begins to rise slowly Early
workers are beginning TO stir; the city is
getting in its milk forsthe day. and from 4
to there is a gentle rise In the amount Of
! sVctricity used. AT 8 o'clock the Nine begins