Electrical Facilities Keep Pace With Missoula by John A. Forssen
[Reporter John Forssen of the Missoulian wrote the article below in 1953. It gave a valuable profile of Missoula’s electrical capacity and a view of it’s history and growth:]
The growth of Missoula in population and in industry has brought with it additions to electric power and distribution facilities culminating in a project which has occupied the Montana Power Co. for the past three years.
Missoula’s growth has puzzled a lot of people because of the lack of any huge industrial development or any of the other usual stimuli to city expansion.
But the power company figures it has the answer in the tremendous increase in the lumbering industry, use of electricity by sawmills, a reliable indication of the amount of timber cut, the amount of lumber and wood products manufactured and the number of persons employed, has increased about 600 per cent in the past five years.
The city and its immediate suburbs now contain more than 32,000 people as compared with somewhat over 20,000 in 1940. And there’s no indication now that the growth will cease.
So the power company began planning an expansion program to take care of the growing city and surrounding area served by the company.
Individual Increase
Company engineers – and most of the executives carry slide rules around with them – had also to contend with the growing use of electricity by individual residential customers.
Residential use averaged about 1,300 kilowatt-hours annually in 1940. Last year it was a phenomenal 3,900 and the present figure is 4,062, continuing the trend.[1]
The result of the planning and the work which followed, to which finishing touches are now being applied, is an entirely revamped distribution system which “will handle anything our customers might want to hook on to it,” said Harry McCann, affable Missoula division manager for the company.
The company has invested many thousands of dollars to provide facilities for ample supplies of electricity to all its customers. The expansion program has resulted in an investment running well into six figures.
The biggest part of the overall project was installation of three new transformers and a new oil switch to open and close 100,000-volt circuits. This equipment is part of what amounts to an entire new substation the power company’s plant near the Higgins Avenue Bridge.
The chief feature of a substation, to the casual observer, is a lot of poles with wires running all over the place, apparently without purpose or plan.
Actually, of course, all the wires are not only precisely placed to serve their particular purpose but are of the exact size and material required for the job.
Forest of Poles
With the addition of the new substation equipment, the plant on the river bank now looks like a forest of poles, all neatly painted white and placed to form a reverse “L” shape. At various heights on the poles wires are hung from, or placed on top of, huge porcelain insulators, some more than two feet long.
The purpose of all this equipment is to receive the power coming into Missoula and prepare it for distribution to the more than 11,000 customers in the Missoula area and 3,500 in the Bitter Root Valley, increases of more than 50 per cent in the past 10 years.
The capacity of the substation expressed in kilowatts, was increased by the new equipment from 22,000 to 32,000.
Due to the interconnection of Montana Power Company generating and distribution lines with the Northwest Power Pool – comprising all generating facilities in the Northwest – power could come to Missoula from any place in the Northwest .
Actually most of it comes from Kerr Dam at Polson, where, incidentally, the power company is installing a third generator to increase generating capacity by 60,000 kilowatts, and from the Thompson Falls dam.
Little of Missoula’s electricity comes from the Northwest, where power shortages are common. The Montana Power Co. regularly exports excess power – as much as 125,000 kilowatts – to the “brownout” areas of the Northwest.
Electricity comes to Missoula at 150,000 volts because it is more efficient to transmit at high voltages. When it arrives in Missoula it is stepped down to lower voltages.
Formerly this was 3,300 volts. Now, with more customers to serve and the customers using more electricity, the company has a 12,500-volt primary distribution system which provides “far greater” capacity, making more electricity available to the customer.
Providing a new primary distribution system was one of the main phases of the company’s expansion program.
Final work is still going on to complete the ring distribution system. Where formerly a series of lines fed out of the substation, now there is a ring roughly a mile in diameter and centered approximately on the substation.
The ring is fed by several lines from the substation somewhat like the spokes of a wheel. From the outside of the wheel feeders fan out farther to provide the lines from which the wires in the alley behind your house are tapped.
All this is approximate and theoretical, since Missoula did not oblige the power company by growing evenly in all directions. The surging city is bulging out to the south and west and is lapping at the foot of mountains to the north and east.
But the principle works and provides a distribution system which supplies plenty of capacity for the city’s present and its future.
Another feature of the expansion program was providing a third source of power for the city. This was done by constructing a double-line connection between the Milwaukee Railroad’s 100,000-volt line across the Clark Fork River to the substation.
This makes it possible to tap the Milwaukee from either east or west. The third power source is the Kerr Dam line, which crosses the hills north of the city on its way to Anaconda.
Rerouting and improvement of the Pattee Street circuits, part of the ring distribution system, also was a feature of the power company’s improvement program.
A big job not directly connected with the expansion program was moving of the operating center from the office, 134 E. Broadway, to the substation.
The center, which includes the radio and dispatching facilities of the company is the nerve center of the division. Hundreds of radio messages are transmitted daily to and from repair crews, the headquarters office and the 21 radio-equipped vehicles in this area.
Increases of power on the power company’s system this year and next will further improve Missoula’s electric picture. The third generator at Kerr Dam near Polson will bring the company’s generating capability to 586,000 kilowatts.
This figure compares to the average requirements of Montana Power Co. customers during 1952 of 349,368 kilowatts, indicating that the company will further improve its position of having surplus power.
The article above also featured four photographs of the substation facility’s new equipment. The captions for these photos are quoted below:
A bright evening sky silhouettes the forest of poles of the 32,000 kilowatt substation which serves the electrical needs of Missoula and the Bitter Root Valley. The section at left, of 10,000 kilowatt capacity, has been added in a major expansion program of the Montana Power Co. The substation now has 12 big transformers which will reduce 100,000 volts to either 44,000, 12,500 or 3,300.
These transformers are the giants of the Montana Power Co.’s equipment. With an accompanying constant “frying” sound, the three 10,000-kilowatt transformers reduce the hot stuff of the 156,000 Kerr Dam line to 100,000 volts. The Kerr line is tapped here, near the company’s Rattlesnake water storage dam by means of the electrically operated switches on the structure at the right, and the 100,000 volts transmitted to the substation in town, about four miles away. At this substation about 1,500 kilowatts of electricity is tapped off the windings of the transformers to stabilize the current. The highly technical reason involves suppression of third harmonics, whatever that is. Anyway, the only use of the 1,500 kilowatts of capacity, enough to light most of the East side, is to operate two light bulbs in a small building at the substation.
Part of the new equipment added to the main substation of the Montana Power Co. in its expansion program is shown here. At left is one of the three transformers in the bank of 10,000 kilowatts capacity. The triple black structure with horns in the center is an oil switch for opening and closing the east leg of the 100,000-volt Milwaukee Railroad line. The angled structure above holds other switches used in conjunction with the oil switches. To the right of the angled structure are the poles carrying the Milwaukee line across the Clark Fork River, and at extreme right are poles carrying one of the city feeder lines.
Many Missoula industries have grown in size and converted to electric power to the extent that the Power Company has established separate substations to serve them. Typical is this one, with poles and transformers pictured before a background of a big sawdust bin.
The above article appeared in the Missoulian on May 3, 1953.
Today the average 2,000 sq. ft. home uses about 1,000 kilowatts of energy per month