Thermal generation
Puget Sound Energy strives to ensure reliable electric service at a reasonable cost by acquiring power supplies from a variety of
different sources, both PSE-generated and purchased from other suppliers. These sources primarily are hydropower, wind power,
natural gas-fired generation, and coal-fired power from Montana. This diversified-portfolio strategy minimizes risk – and costs – in
the event that an unforeseen circumstance (a drought, for example) causes regional shortages in one form of power and, in turn,
drives up wholesale power prices.
Electricity from clean-burning natural gas-fired generating stations makes up about one-fifth of PSE’s total power-supply mix. PSE
currently owns nine facilities, all in Washington state – Encogen, Ferndale, Frederickson, Frederickson 1, Fredonia, Goldendale,
Mint Farm, Sumas and Whitehorn.
Six employ modern, “combined-cycle, combustion-turbine” technology that allow the facilities to generate electricity using both
a natural gas cycle and, from the exhaust heat of its power-generating turbines, a steam cycle. The two-stage process boosts
operating efficiency, lowers fuel costs, and cuts air emissions. Combined-cycle plants often operate to help meet utility customers’
base power requirements. They also complement hydro and wind-powered generation because gas-fired plants can operate on a
firm schedule, while power generation from hydro and wind-generating facilities is dependent upon Mother Nature.
The other three plants – Frederickson, Fredonia and Whitehorn – have single-cycle generating units and are used primarily to
provide back-up “peaking” energy for our power system during daily or seasonal spikes in customers’ power usage. Additionally,
Federickson and Whitehorn have the ability to be started remotely from PSE’s electric-dispatch center and reach full generating
output within 10 minutes.
Encogen Generating Station
Encogen is located in Bellingham, Wash., about 90 miles north of
Seattle. The plant is situated east of the Port of Bellingham’s waterfront
redevelopment site. The facility came online in 1993, and was acquired
by PSE in 1999. PSE became the plant operator in 2005.
PSE’s Encogen Generating Station
Ferndale Generating Station
Built in 1994 by Tenaska Washington Partners, L.P., Ferndale
Generating Station is located about 100 miles north of Seattle, near
Ferndale, Wash., in Whatcom County. PSE acquired the facility in 2012.
PSE's Ferndale Generating Station
Frederickson and Frederickson 1
Generating Stations
Frederickson Generating Station
The Frederickson Generating Station and the Frederickson 1
Generating Station are located about 18 miles southeast of Tacoma,
near Frederickson, Pierce County. PSE is the sole owner of the older,
Frederickson Generating Station. In 2004, PSE bought a 49.85 percent
interest in the newer, Frederickson 1 facility (Atlantic Power owns the
remaining share).
Fredonia Generating Station
The Fredonia Generating Station is located 75 miles north of Seattle, or
about seven miles northwest of Mount Vernon in Skagit County. The first
two generating units, installed in the early 1980s, each can generate up
to 104 MW of power. The other two turbine generators, installed in 2001,
each have a 54-MW generating capacity.
Fredonia Generating Station
pse.com
Goldendale Generating Station
Goldendale is located 215 miles southeast of Seattle, roughly 10 miles
north of the Columbia River and the Washington-Oregon border.
Goldendale came online in 2004 and PSE purchased it in February 2007.
Goldendale Generating Station
Mint Farm Generating Station
The plant is located in the Mint Farm Industrial Park of Longview, Wash.,
about 130 miles south of Seattle. The facility came online in January
2008, and was acquired by PSE in December 2008.
Mint Farm Generating Station Puget
Sumas Generating Station
Sumas is located 115 miles north of Seattle in Sumas, Wash., just south
of the U.S.-Canadian border. This facility includes partial PSE ownership
of a 3.7-mile-long pipeline that brings natural gas to the plant from the
Westcoast Energy Station in Huntingdon, B.C., the main Canadian gastransmission supply point into Washington state.
Sumas Generating Station
Whitehorn Generating Station
The Whitehorn facility is located near Ferndale, Wash., about 120
miles north of Seattle. Its two single-cycle units were installed in 1981;
PSE overhauled one in 2006, and the other in 2008. PSE leased the
two generating units until February 2009, and then purchased them
outright. PSE’s original Whitehorn generating unit, installed in 1974, was
decommissioned in 2000.
PSE’s Whitehorn Generating Station
Generating type
Number of
generators
Power output
(Megawatts)
Approx. number
of households
served by output
Personnel (full-time
PSE employees)
Encogen
Combined-cycle,
combustion-turbine
3 gas-fired
1 steam-fired
165
120,000
17
Ferndale
Combined-cycle,
combustion-turbine
2 gas-fired
1 steam-fired
270
200,000
21
Frederickson
Single-cycle
2
147
110,000
5
Frederickson 1
Combined-cycle,
combustion-turbine
1 gas-fired
1 steam-fired
275*
200,000
16 full-time
employees of Atlantic
Power’s subsidiary
Fredonia
Single-cycle
4
314
235,000
5
Goldendale
Combined-cycle,
combustion-turbine
1 gas-fired
1 steam-fired
277
200,000
18
Mint Farm
Combined-cycle,
combustion-turbine
1 gas-fired
1 steam-fired
310
230,000
21
Sumas
Combined-cycle,
combustion-turbine
1 gas-fired
1 steam-fired
125
94,000
16
Whitehorn
Single-cycle
2
147
110,000
3
* PSE’s total share of capacity is 138 MW.
pse.com
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