Evening star. [volume] (Washington, D.C.) 1854-1972, 1909-12-12

ment floor The basement OF the turbine
section is occupied by a storage battery
and feed pumps: the second floor of this
section is for the steam turbines and the
electric turbo-generators. On the mez-
canine floor, which runs the entire length
switchboard gallery and visitors gallery.
4 fifty-ton electric crane spans the entire
upper portion of this room.
::
The two stacks are each 212 feet in
height. The inside mea surement at the
base is eighteen feet and the opening
at the top is eleven feet. thus insurnG
an immense draught and an elimination
of black smoke caused by the consumption
of soft coal for which the people of the
District have fought so long. The stacks
have a red brick octagon-shaped pedestal
or base to height of about fifty feet,
and above this are cylindrical in shape
and built of very light buff colored brick.
and ending at the top with smooth roll
ing bell tophead as an ornamental and
graceful climax to each chimney.
There are sixteen immense water tube
boilers, each rated at $40 horsepower,
making a total capacity of $500 horse
power. Twenty-one thousand pounds of
water is the evaporating capacity of each
boiler per hour at 212 degrees Fahrenheit.
at a gauge pressure OF 10 POUNDS. 1nTpe
feed pumps are installed in the basement
for the boilers and are connected to the
hot we'll and city pressure mains. any one
of which is capable of supplying one-half
of the plant and one held in reserve. Four
barometric twin injector conden6erS are
provided and are used as a reserve pre-
caution in case the boiler feed pumps fail
to operate from any cause. or if it would
be more economical at light load.
Two immense vertical centrifugal cir
nlil arn Ia 1pl at he
house, each coupled direct to a 20O-horse-
power electric motor and capable of sup
plying sufficient condensing water to the
condensng plant. This condensing water
Is pumped through twenty-four-inch
iron pipe from the river to the plant. and
the overflow water from the hot we'll is
taken to the river by gravity through a
forty eight-inch inside diameter concrete
overflow Hume.
Not by any means the least of the
economical features in connection with
the plant is the coal and ash handling ap-
paratus. Coal is delivered at the station
from railroad cars on a siding just at the
back door of the building. It is first
dropped from the cars into a hopper pit
and is then mechanically conveyed to and
through crushers and thence to the coal
bunker on the top floor by means of belt
conveyors. From the bunkers 1t is fed
to the boilers through chutes and con-
tnuously fed forward into the fire boxes
by steam-actuated mechanical stokers
The ashes are automatically dropped into
ash hoppers under each boiler ind then
I'm turn dropped into hand dump cars.
These hand cars are rolled to the ash pit
III the rear Of the plant and from this pit
are conveyed by ash skips to the top Of
the building. where they are dumped into
chutes suspended over railroad cars. 10 be
hauled away.
The electrical equipment consists Of
four 2.O0O-klowatt Westinghouse iIori-
zontal three-phase T1rbo generators, o!
6,6tO volts pressure. connected to Four
.. 100 horsepower NEUTRALITY-SUSPICIOUS.
turbines. Current is delivered to the sub
station at 6,GGO volts pressure, and there
TRANSFORMERS to the lower voltages Of 125
volts for lighting circuits and 200 volts
for power circuits. There is also installed
a seventy-four-cell storage battery. so
that in case of any extraordinary acct
dent occurring to the engines or genera
tors, current may be had Immediately
from these storage cells.
An extremely handsome white marble
switchboard is erected, having nineteen
sc parate places for controlling the gen.
orators. the substations, the pumping sta
ton. lighting and motor transformers.
y new departure has been made in the