Jim Bridger Plant Point of Rocks, Wyoming

Jim Bridger Plant is named for the renowned explorer and mountain man, John “Jim” Bridger. His pioneering spirit is alive today in the way this power facility has responded to its role as a low-cost energy producer, resource manager and environmental steward.

Energy, a natural resource

A massive amount of energy is held by

nature beneath the rugged, beautiful face

of Wyoming: oil, gas, uranium, coal.

That geologic legacy is the foundation of what today is one

of the largest electric generating complexes in the Rocky

Mountain area: the coal-fueled Jim Bridger steam-electric plant.

Sub-bituminous coal stretches out for miles just beneath

the surface of southwestern Wyoming; the product of

forests and swamps changed by time into vast coal seams.

It is the energy locked in that coal that enables this facility

to produce up to 2,119,000 kilowatts of electricity per hour

from four generating units. That electricity serves people

throughout the West. To get the job done requires the talents

of nearly 350 skilled and dedicated Wyoming residents.

People, power and production

Converting coal into electric energy available at the flip

of a switch can be described in just a few words: coal is

burned to produce high-pressure steam that spins large

turbine-generators, which produce electricity. In practice,

this process requires a complex blending of systems.

Four operating units, each with a 2,800-degree furnace,

produce 1,000-degree steam, which turn turbines. At full

load, the four turbines generate enough electricity to light

three cities the size of Salt Lake City. To accomplish this

task takes a well-trained workforce operating as a team

24-hours a day.

Coal, the starting point

The production process begins with the extraction of

coal from mines located just a few miles from the plant.

The coal is crushed and transported by a four-mile-long

conveyor belt from the Bridger Mine to the plant and by

train from the Black Butte Mine. Here, fuel handlers mix

and blend coal from different seams to gain

optimum blend for a clean, efficient fuel.

Once blended, the coal is conveyed inside

the plant. There, pulverizers grind the coal to

a talcum powder consistency. This mixture

fuels the boiler. At full load, all four units will

consume 1,100 tons of coal per hour.

The boiler heats water to produce steam that

is superheated and conducted to the turbine,

driving the electric generator.

Electricity produced leaves the plant on

345,000-volt transmission lines to enter the

regional power grid.

Spent steam is condensed back into water using cooling

towers (from which billow large clouds of white water

vapor, giving the plant one of its most distinctive hallmarks).

The cooled water then returns to the boiler to start the

process all over again. Water for the plant comes from the

Green River through a 50-mile-long pipeline.

Engineered for the environment

At every step of production, the Jim Bridger Plant

exemplifies an emphasis on environmental stewardship. On

the mining side, the surface mines near the plant are subject

to rigorous reclamation. What was grazing land before,

returns to grazing land. The land is restored to original or

better condition. Nesting platforms are installed for hawks.

Natural grass and shrub seed is planted for cattle and

wildlife grazing.

TRANSMISSION LINE

GENERATOREXCITER

MAINTRANSFORMER

COOLING TOWER

CONDENSER

COAL SILO

PULVERIZER

BOILER FEED PUMP

BOTTOM ASH

COLD REHEAT

HO

T R

EHEA

T

STEA

M

AIR PREHEATER

FEEDER

PRIMARY AIR SUPPLYFORCED DRAFT FAN

INDUCED DRAFT FAN

FLY ASH

STACK

COAL FROM MINE

ELECTROSTATICPRECIPITATOR

SCRUBBER

STACK

BOILER

ECONOMIZER

TURBINE

How electricity is made at Jim Bridger Plant

The power production process meets Wyoming’s tough

air and water quality standards.

A by-product of coal burning is f ine fly ash, which

is removed from the stream of hot gasses by use of

electrostatic precipitators. These precipitators trap 99.3

percent of the fly ash, much of which is marketed to the

concrete industry.

Jim Bridger coal is low in sulfur content. Sulfur dioxide,

another by-product of combustion, is removed by scrubbers

from all four units.

In addition, Jim Bridger is constantly improving the

containment of airborne dust through such actions as

paving roads and sealing coal stockpiles. There is also strong

emphasis placed on recycling of materials and seeking new

ways to constructively deal with environmental issues as

they arise.

Jim Bridger at a glance

Sponsoring companies:

PacifiCorp Energy, Idaho Power Company

Generating capacity:

2,119,000 kilowatts per hour in four units

Fuel:

Sub-bituminous coal is delivered to the plant by an overland

conveyor from the Bridger Mine. Coal is also transported by unit

train from the Black Butte Mine.

Coal reserves:

The Jim Bridger field has usable reserves of 140 million tons of

low-sulfur coal.

Plant operating personnel:

350 people are employed at the Jim Bridger Plant.

Chimneys:

Each of the generating units has a chimney 500 feet high.

Water supply:

The water supply necessary to operate the plant is delivered from

the Green River through a 50-mile steel pipeline to a reservoir at

the plant site.

Boilers:

Each of the four boilers is designed to produce 3,980,000 pounds

of steam per hour at a throttle pressure of 2,400 PSI. Each

consumes 275 tons of coal per hour. Per year, on average

8 million tons of coal are used. The boilers are 240 feet tall.

Turbine-generators:

Each of the turbine-generators has a nameplate rating of

555,100 gross kilowatts. The units are 131 feet long and weigh

approximately 1 million pounds each.

Completion dates:

Unit 1: November 1974, capacity currently 535,000 net kilowatts

Unit 2: December 1975, capacity currently 527,000 net kilowatts

Unit 3: September 1976, capacity currently 527,000 net kilowatts

Unit 4: December 1979, capacity currently 530,000 net kilowatts

01/11 PC © 2011 Pacif iCorp

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CORVALLIS LEBANON

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MADRAS

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JUNCTION CITY

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COOS BAY/NORTH BEND

ROSEBURG

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MYRTLE CREEK

GRANTS PASSROGUE RIVER

EAGLE POINT

MT. SHASTA

YREKACRESCENT CITY

ST. ANTHONY

LAVA HOT SPRINGS

PRESTON

MONTPELIER

MALAD CITY

SHELLEY

RIGBYARCO

WORLAND

BUFFALOCODY

LOVELL

DOUGLAS

GLENROCKROLLING HILLSGLENROCK III

BIG PINEY

PINEDALE

GREEN RIVER LARAMIEROCK SPRINGS

KEMMERER

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RAWLINS

LANDER

CASPERRIVERTON

THERMOPOLIS

SMITHFIELDLAKETOWN

TREMONTON

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LAYTON

TOOELE

LAKE SIDE

PARK CITY

SANTAQUIN

MORONI

RICHFIELD

GUNNISON

MOAB

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CEDAR CITY

CASTLE DALE

MILFORD

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SALINA

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DRAPERAMERICAN FORKPLEASANT GROVEOREM

SALT LAKE CITY

WEST VALLEY CITY

FOOTE CREEK I

MCFADDEN RIDGE I

HIGH PLAINS

BEAR RIVER PROJECT

KLAMATH RIVER PROJECT

NORTH UMPQUA PROJECT

ROGUE RIVER PROJECT

LEWIS RIVER PROJECT

JIM BRIDGER

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DAVE JOHNSTON

COLSTRIP

CRAIG HAYDEN

CHOLLA NO. 4

HUNTER

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HUNTINGTON

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Rocky Mountain Power and Pacific Powerservice area

Idaho Power Company service area

Thermal plants

Gas-fueled thermal plants

Wind projects

Geothermal plants

Coal plants

Principal communities served

PacifiCorp-owned transmission lines

Transmission access

Other transmission

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Power network

Recreation on the Jim Bridger Reservoir

Generating recreation opportunities with the same

resources we use to generate power is one additional

way we provide for the community.

The recreation opportunities along the Jim Bridger

Reservoir are open year round for day use. Located

approximately 35 miles east of Rock Springs, Wyoming,

our facilities provide river and reservoir fishing, picnicking

and hiking opportunities.

Visit pacificorp.com/recreation for details about recreation

amenities – and any fees – at our recreation areas.

Pacif iCorp is one of the lowest-cost electricity producers in the United States, providing approximately 1.7 million customers

in the West with reliable, eff icient energy. Pacif iCorp operates as Rocky Mountain Power in Utah, Wyoming and Idaho, and

as Pacif ic Power in Oregon, Washington and California. Pacif iCorp’s electric generation, commercial and energy trading, and

mining functions are operated as Pacif iCorp Energy.

For more company information, please visit pacificorp.com and idahopower.com.