POWER March 2011 - 28

PLANT MAINTENANCE
Plant Overview
The San José Power Station is located near
the town of Masagua, Guatemala, about 75
kilometers (km, 47 miles) south of Guatemala
City, the nation's capital. Included
in the project's scope is a fuel-receiving
facility located at Puerto Quetzal on the
Pacific Coast, 40 km away.
The plant was constructed under a contract
with J.A. Jones Construction and
Black & Veatch International on a turnkey
basis. The project included port modifications
to accommodate the importation of
coal, as well as a transmission line to connect
the plant to the Alborada substation.
The project consists of a coal-fired
boiler, condensing steam turbine, cooling
tower, and a substation (Figures 2 and 3).
Low-NOx
burners and a pulse jet fabric filter
complement the low-sulfur coal used as
fuel.
The plant has a DB Riley, coal-fired furnace
with three duplex, Atrita pulverizers
feeding 12 burners in three rows of four
burners each. The boiler feeds about 1,200
kpph of 1,000F/1,905 psia superheated
steam to the turbine.
The single-flow, 11-stage Mitsubishi
turbine has five steam extractions and a
closed-loop condensing system that utilizes
cooling water from a four-section cooling
tower. The generator is a 160-MVA, threephase,
60-Hz, brushless generator made by
Brush (England), directly coupled to the
high-pressure side of the turbine. The plant
also has a 43.2-MVAR capacitor bank to
assist with reactive power.
" All the water used at the power plant
comes from seven wells, with the main
problem being a high silica content due to
the fact that the plant is in a volcanic region
of Guatemala, " de la Torre said.
The plant's electric output is sent via a
17-km 230-kV power line to a substation
near the city of Escuintla, where it is connected
to the national grid.
Operating with an overall efficiency of
10,800 Btu/kWh, the plant generates close
to 1,000 GWh annually. That total may
vary, depending on the rainy season and
the dispatch of hydro plants. Scheduled
maintenance requires between 18 and 30
days per year, and the plant has an annual
availability of approximately 98%.
The Plant's Coal Usage
Almost all the coal used at the plant comes
from Colombia. It is unloaded at the plant's
unloading facility close to Puerto Quetzal
on the Pacific Ocean and then is transported
to the plant site by a company-owned
fleet of trucks that make approximately 70
shipments per day, six days a week. At full
28
load, the plant consumes about 1,300 tons
of coal per day (Figure 4).
" Most of our coal comes from the Atlantic
Coast of Colombia in South America.
And because [the plant] is located on
the Pacific coast, that means that each coal
shipment goes through the Panama Canal, "
de la Torre said. " We have used coal from
Canada in the past, but the severe winters
and higher price has discouraged us from
using it. "
One limitation is that all coal vessels
must be self-unloading, due to the design
of the port facility, de la Torre pointed out.
This requirement narrows the availability
of coal transport vendors.
Workforce Challenges
The San José plant is staffed by 76 employees,
including the plant manager, an
operations manager, a maintenance manager,
eight staff engineers, miscellaneous
office staff, and five shift crews each composed
of eight workers. TPS Operaciones
de Guatemala Ltd. is responsible for plant
operations.
" We have found that technically prepared
individuals are extremely difficult
to find in a country whose main economy
is based on agriculture, " de la Torre said.
" In order to retain our staff, our company
has a policy of keeping salaries and wages
within the 'top five' in the country. Being
the first coal-fired plant in the area requires
a lot of training, and today only an
18-MW coal-fired plant has been added to
the Guatemalan grid, although others are
under construction. "
Another challenge is language, according
to de la Torre. Most technical publications,
books, and manuals are in English,
so learning a second language has been
a big challenge for the plant's Spanishspeaking
employees.
" The third challenge is to develop a
culture of safety, " he said. " There are very
low standards in the Guatemalan industry
regarding safety and environmental compliance;
however, there are several companies-including
TECO Guatemala-with
high standards. Creating a safe environment
has required a continuous effort since
day one. "
The San José plant adheres to Guatemalan
and U.S. standards, including those
enacted by the Environmental Protection
Agency and the Occupational Safety and
Health Administration.
TECO Guatemala invests time, resources,
and money to train its team members by
providing the tools for their personal and
professional growth. TECO Guatemala also
offers safety and first aid training to team
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POWER | March 2011
4. From coal to electrons. The plant's
coal-handling area is shown. At full load, the
plant consumes approximately 1,300 tons of
coal per day. Courtesy: TECO Energy Inc.
2. 21st-century know-how. The San
José Power Station, including the control
room shown in this photo, contains current
technology that allows it to operate with great
efficiency. Courtesy: TECO Energy Inc.
3. Keeping things under control.
San José's control room is the nerve center of
the facility. Courtesy: TECO Energy Inc.
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POWER March 2011

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