THE OMAHA SUNDAY BEE: APRIL 11. 1!00.
No. 12
POW
E R
s.
4 .
The majority of people have not the remotest conception
of how power to run street cars is obtained and applied, nor of
the machinery and expense involved. It would require many
articles the length of this one to make the subject reasonably
clear to the uninitiated, but a few general facts may be given
which help the reader appreciate the investment and operating
costs.
Electricity is the product of friction. . Steam is the pro
duct of heat and water. To produce electricity by friction,
steam power is used. Therefore, it is necessary to have, in
the first place, boilers and steam en
gines to drive the friction machines,
called generators or dynamos.
Fully one-half the power in
stallation of a street railway com
pany is used less than four hours a
day. The heavy investment in the
boilers, engines and generators
which lay idle 20 out of the 24
hours is due to the nature of the
traffic, which culminates in two
"peaks" during the rush hours of
the morning and evening. The aver"
age non-rush hour electrical load
of our system is about 2,100 kilo
watts; the electrical load at 6 p.m.
on an ordinary week day is 5,000
kilowatts. It is the maximum, not
the average, demand which the
company must be able to supply.
The investment of the Omaha
and Council Bluffs Street Railway Co. in its central power station,
rotary converting substations and high voltage cables and con
duits, runs into the millions. It will be necessary within
a short time to spend a very large amount for addi
tional power installation.
By 1903, or in a little more than a dozen years, the com
pany had entirely outgrown the two power stations which had
served, with many additions and improvements, from the first
days of electrification. A great deal of the machinery was not
worn out, but it was no longer equal to the demands nor eco
nomical to operate. It was scrapped, most of it sold for junk
and the source of energy centralized in 1904 in the new Jack
son Street Power Station.
The Jackson Street Power Station lies at the foot of Jack
son Street and near the river. It was designed by John J.
Lichter of St. Louis and it supplies motor energy for the whole
system. The actual maximum capacity is more than 10,000
electrical horsepower. From skylight to foundation piers the
station and equipments are modern, efficient and costly.
The building consists of duplicate sections, each 130 feet
long and 54 feet wide and 75 feet high. Construction is largely
of steel and concrete with brick walls. The roof is covered
with tile. The east section of the building is the boiler room;
the west section is the engine-generator room.
There are four double batteries of Bahcock and Wilcox
boilers. Each boiler has a capacity of 525 horsepower, mean
ing a total steam horsepower capacity of 4,200.
The engine room contains a Curtis Steam Turbine Alter
nating Generator of 2,000 kilowatts rated capacity; three Gen
eral Electric Direct-current Generators of 1,000 kilowatts rated
capacity each, direct connected to as many Fulton Cross-compound
Reciprocating Engines, and one 850 kilowatt Direct-current
General Electric Generator direct connected to an engine
of the same type. The principal machines in addition to these
.are three rotary converting generators of a total capacity of
1,425 kilowatts.
To run the Jackson Street Station one day requires 150
tons of coal. If the coal is delivered in hopper bottom cars it
ir
! I IS ' - rffi tM I if
If
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X
Engine-Generator Room, Jackson Street Power Station.
is never touched by hand or shovel, but is transported from
car to grate automatically by means of coal conveying machin
ery. If the cars are not hopper bottom it is necessary to shovel
the coal into the receiving pit.
The fuel is first put through the coal crushers and then
carried by belt conveyers to the coal bunkers which are located
high above the boilers. These bunkers will hold 300 tons.
From the bunkers the coal descends by gravity through iron
spouts to a position directly over the open or receiving end of
the chain grates. The grates are continuous and moving for
ward automatically at the desired
rate of speed, carry the coal in a
layer, of from 5 to 6 inches under
the boilers where the greatest pos
sible degree of heat is extracted.
Even the ashes are handled by
automatic conveyers and dumped
into cars waiting to receive them.
Stoking, in the old sense of the
term, is no longer known in a plant
like this.
The boiler furnaces are opera
ted under an induced draft ob
tained by the use of duplicate
vacuum fans 22 feet in diameter,
Between the fjurnaqes and the stack
are located a series of radiators
known as fuel economizers which
are used to heat the boiler feed
water. The economizers utilize as
much as possible of the products
of combustion which escape through the chimney.
All of the steam used in the plant after performing its
work in the turbines and engines is passed over pipes contain
ing cold river water and condensed. Thus the water is used
over and over again and never allowed to become cold. The
circulating system necessary to obtain the desired results is too
complicated to describe, but it may be stated that when water
enters the boilers it has already been heated to a temperature
of from 225 to 25Q degrees.
The street cars are moved by what is known as direct current electricity
placed on the wires at a pressure of 600 volts. To enable' the proper and
economical distribution of power, however, a large proportion of the electrical
energy is manufactured in alternating or high speed current at 13,200 volts.
Part of this is sent to the substations and converted into 600-volt direct cur
rent energy. The remainder is likewise converted at the central station and
used to feed the trolley wires.
The principal Substation at Twenty-seventh and Lake Streets is a costly
investment in itself. The building is of concrete with brick curtain walls. The
13,200 volt alternating current from the Jackson Street Station is conveyed
through three-wire cables in underground clay conduits, entering the Substa
tion through oil switches built in a fireproof Vault. The current is run through
air-blast cooled transformers, which reduce the voltage to 430 and is then sent
through the rotary convenors, which change the alternating current into direct
current suitable for the trolley wires. The converting capacity is 800 kilowatts.
The transforming and converting apparatus at Jackson Street is similar
but of larger capacity.
VThe company maintains a Portable Substation housed in a specially con
structed car which may be taken to any partf the line. This Portable Sub
station is found very useful in summer in handling the heavy Lake Manawa
traffic. ' It has a transforming-converting capacity of 400 kilowatts.
The interior of the Jackson Street Station is exceptionally pleasing to the
eye of the layman, even though he may not be of a mechanical turn of mind.
Tile floors, ornamental iron lamp brackets, automatic ventilating devices and
a general atmosphere of spotless order and cleanliness prevail.
There is .nothing to indicate to the senses the terrific power concealed
in the high voltage mechanism under the sole control of the switchboard
operator, who from his isolated perch directs it into its proper channels, not by
insulated hand devices, but by low-voltage electric switches, which in turn
control the power which is too dangerous to risk personal contact.
There is some likeness between the unseen forces that exist in this sta
tion and the unseen hundreds of thousands of dollars which have gone into it.
G. W. WATTLES, President,
Omaha and Council Bluffs Street Railway Co.
(Next Sunday a Article Wilt Be Devoted to the 'Trainmen and Other Employes )