PRIME MOVERS AND POWER PLANT MACHINERY.
that supply cheap hydroelectric generated power. In Kansas, Okla-
homa, and Texas most of the electric power used by the oil companies
is similarly procured. However, in some of the Mid-Continent and
Appalachian fields, some of the companies have built their own
electric power plants.
If a hydroelectric plant is impracticable, local conditions will
determine which type of prime mover will be used to generate the
electric power. For large power-plant installations, a steam-turbine
plant is generally much cheaper than a gas engine installation.
If natural gas is available a gas engine plant is usually the cheap-
est to install and operate for requirements of less than 500 horse-
power. Both vertical and horizontal gas engines in units up to 200
horsepower are used. If one unit of 200 horsepower does not furnish
enough power, several units can be used in parallel.
If the supply of natural gas is too low, oil engines will give high
economy, although their installation costs are higher than for
gas engines. Like gas engines, their size is limited but they can be
operated in parallel. Steam boilers and engines may also be used
and if much power is needed the steam turbine used as a prime
mover is the most desirable because of its low first cost and upkeep
and its simplicity of operation. Two or three turbine units are
generally advisable instead of one larger one, to reduce the chances
of all the power being " off " at one time.
A steam, gas, or oil engine for driving the electric generator can
use either belt or shaft drive; the former is, however, the cheaper to
The writer recently visited a modern electric power plant built by
one of the larger producing oil companies in one of the Gulf Coast
oil fields. This plant was built to eliminate the scattered smaller
power units of various types formerly used, which had proved costly
and inefficient. The plant was completed in 1920 at a cost of about
$465,000; since then it has run continuously and has shown a
saving of more than $1,000 a day over former operating costs. This
plant is well housed in a steel building with concrete floors. It has
three power units, each consisting of a 300-horsepower boiler, a steam
turbine driving a generator of 625 kw. capacity at 900 r. p. m., and
producing electric current at 2,400 volts, 450 amperes, 3 phase and
Two units of the plant are kept running continuously, and the
third is run during periods of peak load. The boilers are cleaned
once a month. Water purifiers and heaters are used. Boiler feed
pumps are used for forcing water into the boilers, and a centrifugal
pump driven by a 5-horsepower motor brings water to the pump at
George, H. C. Surface Machinery and Methods for Oil-Well Pumping. Washington D.C.. UNT Digital Library. http://digital.library.unt.edu/ark:/67531/metadc12407/. Accessed October 25, 2014.