TECO Energy's subsidiary, Tampa Electric, operates five power plants. They are:
- The largest plant is Big Bend Power Station, based in Tampa, Fla. Big Bend is predominantly a coal-fired plant with some oil-fired peaking capacity.
- The newest facility is the H.L. Culbreath Bayside Power Station, based in Tampa, Fla. Bayside is powered by natural gas. It replaced the retired Gannon Power Station.
- Polk Power Station is based in Polk County, east of Tampa, Fla. The largest unit operates with a special coal-gasification technology. In addition, Polk has two peaking units and is building two additional units.
- Partnership Station, also in Tampa, is a small cogeneration facility which sells waste heat to Tampa's sewage treatment facility.
Bayside Power Station
Located on Port Sutton Road near Tampa Bay, H.L. Culbreath Bayside Power Station provides approximately 1,800 megawatts of natural gas-fueled electric energy.
Coal firing of units at Gannon Station ceased operation in 2004. Units Five and Six are repowered with new technology fueled by natural gas. Bayside Unit One (Gannon Five repowered) began commercial service in May 2003 and Bayside Unit Two (Gannon Six repowered) began commercial service in May 2004.
The project integrates seven combustion turbines and seven heat recovery steam generators (HRSG) to two of the plants' existing steam turbines to reliably and cost effectively produce 1,800 megawatts of power.
The decision to repower to natural gas was based on:
- Increasing customer growth resulting in demand for reliable electricity;
- Ability to meet more stringent environmental regulations;
- Utilization of existing substations and transmission facilities;
- Availability of natural gas from proposed natural gas pipelines in the area;
- Opportunity to reuse existing plant equipment.
By using natural gas at H.L. Culbreath Bayside Power Station along with high efficiency, state-of-the-art controls at its newer remaining coal-fired plants, Tampa Electric will be able to significantly reduce emissions and meet growing energy needs well into the future. H.L. Culbreath Bayside Power Station emits almost 99 percent less nitrogen oxide and sulfur dioxide, plus over 85 percent less particulate matter than Gannon Station.
- Increasing customer growth resulting in demand for reliable electricity;
Big Bend Power Station
Situated on Tampa Bay, Big Bend Power Station is located on Big Bend Road on nearly 1,500 acres in southeastern Hillsborough County, close to Apollo Beach.
Big Bend Power Station has four coal-fired units with a combined output of more than 1,800 megawatts. Big Bend Power Station expanded to meet the demands of rapid growth during the 1970s and 1980s. The first unit began service in 1970; the second and third generating units were added in 1973 and 1976; and Unit Four was added in 1985. With the capacity provided by three combustion turbines that serve as peaking units, combined output from Big Bend Power Station is 2,000 megawatts.
Big Bend Power Station meets strict environmental regulations through the use of a flue gas desulfurization (FGD) system or scrubber, which removes sulfur dioxide produced when coal is burned.
The scrubber for Big Bend Units One and Two began operation at the end of 1999. The scrubber for Big Bend Unit Four began operation in 1984, and since 1995, has simultaneously scrubbed Unit Three as well. The FGD system complies with standards set by the U.S. Clean Air Act Amendments of 1990, and removes 95 percent of sulfur dioxide from all four units.
By using a variety of proven technologies, Tampa Electric expects to significantly reduce oxides of nitrogen (NOx), particulate matter, sulfur dioxide emissions from Big Bend Power Station. Planned actions include:
- Tampa Electric is installing Selective Catalytic Reduction (SCR) technology to reduce nitrogen oxide emissions from the plant. This project will cost approximately $300 million and will reduce nitrogen oxide emissions at Big Bend Power Station by roughly 85 percent from 1998 levels by 2012.
- Optimizing the electrostatic precipitators to minimize emissions of particulate matter from the stacks. By 2004, all improvements will be implemented, resulting in a reduction of approximately 59 percent when compared to 1998 levels.
- Further reduction of sulfur dioxide emissions by investing more than $23 million in scrubber upgrades, resulting in a reduction of over 80 percent from 1998 levels.
During the scrubbing process, coal combustion gases are sprayed with a mixture of water and limestone. Sulfur oxides react with the spray to form gypsum.
Tampa Electric recycles virtually all of its gypsum. The byproduct is used locally:
- In wallboard (drywall) for construction;
- In cement and concrete for construction;
- And in agriculture as a soil nutrient, fertilizer or “sweetener.”
Fly ash, a fine particulate material that results from the combustion of coal in all four Big Bend Units, is used in the cement and concrete industries.
Slag, a solid byproduct, is a hard glassy material with many reuses, including cement. Its hard quality makes it valuable to use as a blasting material to clean ships and other large surfaces.
Polk Power Station
Polk Power Station occupies 4,300 acres on State Road 37 in Polk County, Florida. It is located approximately 40 miles southeast of Tampa and about 60 miles southwest of Orlando.
A state-of-the-art integrated coal gasification combined-cycle (IGCC) power plant, Tampa Electric's Polk Power Station produces enough electricity to serve 75,000 homes.
The project was awarded $120 million from the U.S. Department of Energy (DOE) for the development of a project using clean coal technology. As part of a cooperative agreement with the DOE, TPS is also concentrating on commercialization of this IGCC technology.
Construction on Unit One began in 1994 on a site selected by a public Power Plant Siting Task Force comprised of 17 citizens from environmental groups, businesses, and universities in the Tampa Electric Company service area and throughout Florida. The objective of the Power Plant Siting Task Force was to ensure that local and statewide public issues and environmental concerns relative to new power plant development were adequately and accurately considered in selecting a suitable site for the new power plant.
Polk Unit One is located on unmined land surrounded by former phosphate mining land to the east, and a berm developed as a cooling reservoir to the south. The design of the maximized plant water recycling and re-use, and minimized groundwater withdrawal and offsite discharges.
The 250-megawatt IGCC facility began commercial operation in the fall of 1996. Construction on Polk Unit Two began in 1998 and Unit Three in 1999. These two 180-megawatt simple cycle combustion turbines use natural gas and distillate oil to generate electricity. Unit Two started commercial operation in July 2000. Unit Three started commercial operation in May 2002.
The 250-megawatt IGCC facility is among the nation's cleanest, most efficient and most economical power generation units. The plant is a first-of-its-kind combination of two leading technologies.
The first technology is called "coal gasification," which uses coal to create a clean-burning gas. The second technology is called "combined-cycle," which is the most efficient method of producing electricity commercially available today.
The plant combines coal with oxygen in the gasifier to produce the gaseous fuel. After processing, the clean coal gas is used in the combustion turbine to produce electricity.
Combined-cycle technology increases efficiency because it reuses exhaust heat to produce more electricity. Combined-cycle design consists of a combustion turbine, a heat recovery steam generator, a heat recovery steam generator, and a steam turbine. The exhaust heat from the combustion turbine is recovered in the heat recovery steam generator to produce steam. This steam then passes through a steam turbine to produce more electricity.
The coal gasification unit provides clean, coal-fueled power, with a minimum of 95 percent of the sulfur in the coal gas. This exceeds the performance of today's most advanced coal-fired generating units. Furthermore, oxides of nitrogen, or NOx emissions are also lower than many of today's most advanced coal-fired generating units. The sulfuric acid and solid byproducts are then sold for industry use.
The plant is considered "zero process water discharge.” A brine concentration unit, which produces an effluent that is reused in the process, handles all of the liquid waste.
The combined-cycle technology requires much less cooling water than conventional technology, and Tampa Electric was able to modify existing conventional “mine cuts” on the phosphate land to become the plant's cooling reservoir.