4. Experience has shown that such neglect produces serious troubles
and financial loss to the manufacturer, and a very decided change for
the better has developed in the last few years. There are, however, a
few small concerns still operating in the producer field on what may
be considered a false basis.
Centralization of Power Development and Distribution.
Central stations for power and lighting are springing up all over the
country. Electric lights are now in general use in towns numbering
their population by hundreds only. Electric transmission for
street-railway service is practically universal and electric power for
shop drive is in great demand. The substitution of the electric
locomotive for the steam locomotive for terminal service and even for
line duty by several leading railway systems is no longer a mere
expectation but is an every-day working reality.
These changes and developments in every section are, to a large
extent, tending to do away with the individual small steam equipment,
whether stationary or locomotive, and are bringing to the front the
central power station, ranging in size from lighting and pumping
plants of less than 100 horsepower in the smaller towns to those of
100,000 horsepower or more required to meet metropolitan demands. 366
European Examples of Advantageous Location.
In the development of central power plants and the reduction of the
cost of power, the producer-gas power plant is an important factor. In
this connection the question of locating such plants directly at the
mines is well worth careful and unbiased attention in the engineering
profession. The advantages to be derived from such a location have
already attracted the commercial interests of Europe. As examples
worthy of thoughtful consideration, the general conditions of
operation of three typical European installations are here described:
Plant A.--This plant, although not situated directly at the mines, is
but a short distance away, and the company owning the plant also owns
the mines from which the fuel is secured. The plant is of the Mond
by-product type and consists of eight pressure producers of 2,500
horsepower each. The fuel used is a run-of-mine bituminous coal said
to contain 8 to 9 per cent ash and 1 to 2 per cent sulphur. This would
indicate that they are utilizing the best grades of coal from their
own mine in the local gas plant and allowing the lower grades to
remain unmined, a fact which I verified before leaving the plant.
The plant is designed for the recovery of the sulphate of ammonia and
for supplying gas to the neighboring towns for both metallurgical and
power purposes. As one unit is always held in reserve, the plant is
called 16,000 horsepower. The main distributing line is 3 feet in
diameter, and at the time of my visit there were 37 miles of main, the
longest single run being 6½ miles. Each producer gasifies, on an
average, 20 tons of coal per twenty-four hours. The report of the
engineer in charge indicates that the plant had been in operation
twenty-four hours a day, seven days a week, for two and one-half 367
years without a shut down.
Plant B.--This plant, which is located in the center of a peat bog,
proved of especial interest. It has a capacity of 300 horsepower only,
and is about 3 miles from the town to which the electric current is
supplied. One-half of the plant (150 horsepower) was installed in 1904
and the remainder in 1906. This is probably the first as well as the
smallest producer-gas installation to be located at the mine and
transmit high-voltage current to a point some distance away. This
installation, in 1909, consisted of two suction producers (special
peat type) rated at 150 horsepower each, and two horizontal twin
single-acting four-cycle gas engines of 150 horsepower each, direct
connected to alternating-current three-phase generators, which were
running splendidly in parallel at the time of my visit. The 3,000-volt
current is transmitted to the town, where it is used during the day
for lighting shops and for shop motors. At night the plant supplies
the lights for the streets and residences. The charge for residence
light is 9 cents per kilowatt hour. Both units are in operation from
5:30 a. m. to 6 p. m., and one continues to 11 p. m. each day.
A 35-horsepower peat machine is used for preparing the fuel. This is
driven by an electric motor supplied with current from the power plant
on the bog. As only 750 tons of dry peat are required per year there
is no attempt to work the plant to its maximum. Local farmers are
employed and they work as little or as much as they please, as there
is no difficulty in getting out all the peat needed for a year during
the working season, which in this locality is from April 15 to
September 1. As a result 14 men are employed more or less of their
time. They receive about 50 cents per day each and get out about 20
tons of peat per day.
Coal at this point in Europe costs $3.75 per ton. The dry peat 368
delivered on the operating platform of the producer plant costs only
80 cents per ton.
Plant C.--This plant is installed at the collieries. At the time of my
visit it was under full operation, using roof slabs that gave little
indication, on casual inspection, of containing any combustible
material. It was claimed that this fuel averaged over 60 per cent
ash--a claim which seemed entirely reasonable. At the time of this
visit (1908) the producers were not only supplying a number of
furnaces with gas, but were also operating a 1,000-horsepower and a
250-horsepower gas engine. A 500-horsepower engine was being added to
the equipment. The engines in use were direct connected to electric
generators. The 10,000-volt current is used for operating the local
mine machinery and also for furnishing lights for neighboring towns
and power for a street railroad. The plant was reported to be using
over 100 tons of this low-grade fuel per day.
Favorable Conditions in the United States.
In the United States cheaper power is constantly sought. The
water-power possibilities of the country are being realized and the
hydro-electric power plant is a wholesome cause of competition. The
supply of fuel of marketable grades is not unlimited. Prices for such
fuel must necessarily increase. The cost of transporting coal from the
mines is high, and the possibility of obtaining a sufficient supply of
cars to handle low-grade fuels is questionable. The power demands of
the country are increasing, and this power must be developed at a
reasonable cost. The time is approaching when the cheapest fuel
obtainable must be used to the best economic advantage in order to
develop power at a unit cost consistent with commercial progress.
Consideration of the conditions indicates that in order to keep the 369
price of power developed from fuel down to a consistent figure--
(a) Grades of fuel which warrant transportation, or which may be
defined as “marketable,” should be used with the greatest possible
practicable economy.
(b) The very large percentage of coal of so-called low grade which
today is left at or in the mine must be utilized.
(c) Advantage must be taken of the large deposits of lignite and peat
which are found in many sections of the country.
It is undoubtedly true that in general, under conditions which do not
require the use of steam for other than power purposes, the
producer-gas power plant meets the requirements of (a).
At present the only method of advantageously handling the fuels
mentioned in (b) and (c) is in the gas producer, and the utilization
of these lower grades of fuel on an extensive scale demands
concentration of the power plants within close proximity to the fuel
supply.
The logical conclusion from a careful study of the producer-gas power
situation is that the time is not distant when financial interests in
power production will be directed toward the centralization of the
producer-gas power plant at the mines and the distribution of the
energy developed either by high-voltage long-distance electrical
transmission or by pipe systems for conveying the gas.