DOE - Fossil Energy Techline - Issued on:  June 5, 1997

DOE-Sponsored Clean Coal Project Wins POWER Magazine 1997 Award


Tampa Electric Project is 5th Clean Coal Facility Since 1991 to be Cited for Prestigious Award

For the fifth time in the last seven years, a Department of Energy Clean Coal Technology project has been named as one of POWER magazine's Powerplant Award winners.

PHOTO of Tampa Electric Gasification PlantThe Tampa Electric Power Company's Polk Power Station -- a state-of-the-art coal gasification combined cycle power facility near Lakeland, FL -- is one of three electric generating plants selected to receive the prestigious industry award for 1997. The award was presented this week at the magazine's Sixth Annual Powerplant Operations and Maintenance Symposium held in Newport, Rhode Island.

"POWER magazine is one of the most distinguished publications in the electricity generation industry, and we are delighted that its editors continue to recognize the pioneering achievements of the Clean Coal Technology program. We congratulate Tampa Electric and its partners on a project that is receiving well-deserved recognition as a pacesetter for the power industry of the 21st century," said Secretary of Energy Federico Peña.

Dedicated in January 1997, Tampa Electric's 250-megawatt power facility is one of the cleanest coal-fueled power stations in the world. Because it first turns coal into a gas, then filters out acid-rain and smog-causing impurities, the plant achieves emission levels much closer to a natural gas plant than a traditional coal-burning facility. More than 95% of the sulfur pollutants in coal are removed and converted into commercially valuable products.

POWER magazine's editors took special note of the plant's capability to turn a pollutant into a product. "One way coal-fired generation can compete in the next century is if the fuel is considered for more than its heating value, and the facility more than just a powerplant. Polk is demonstrating just such a holistic approach," the editors wrote.

The plant is also one of the world's most energy efficient. Once cleaned, the coal gases are first burned in a gas turbine, then the turbine's exhaust heat is used to boil water for a conventional steam turbine-generator. The combination of gas and steam turbines -- the "combined cycle" aspect of the plant -- pushes operating efficiencies to 40%, compared to a conventional power plant's typical 33%-efficiency level.

Higher efficiencies means that fuel is conserved and greenhouse gas emissions like carbon dioxide are reduced. Ultimately, as efficiencies are increased even more, gasification combined cycle power systems are expected to cut carbon dioxide emissions by nearly 40% compared to a traditional coal plant. A more efficient plant also reduces electricity costs to ratepayers.

The Tampa Electric Polk Power Station is the first in the United States to use the advanced gasification combined cycle process in a full-size, commercial "grassroots" plant -- a plant built entirely new. The facility is planned as the centerpiece of a larger power generating complex being built on environmentally reclaimed land previously mined for phosphates. As part of the overall project, Tampa Electric is converting a third of the 4,400 acre site into a wetlands habitat for wildlife.

At Tampa's Polk County plant, a Texaco-supplied pressurized, oxygen blown, entrained flow gasifier is converting coal into a combustible gas. The coal gas is burned in a General Electric advanced combustion gas turbine to generate electricity. Exhaust heat from the gas turbine is being recovered to produce steam for a steam turbine generator. It is this combined cycle using two turbines that accounts for the technology's high efficiencies.

The Polk Power project is also providing the first test of a "hot gas cleanup" system. General Electric's hot gas cleanup system will remove approximately 95% of the sulfur pollutants and particulates. Designed to operate at the elevated temperatures of the gases exiting the coal gasifier, the new system helps keep power plant efficiencies high. Older, conventional cleanup systems must cool the gas before removing pollutants, a step that robs efficiency.

The new cleanup system uses an intermittently moving bed of metal oxide-based sorbent to remove sulfur-bearing compounds and residual dust from the syngas produced by the gasifier. The advanced cleanup technology will process about 10% of the syngas as part of the first-of-a-kind test program. The remainder of the gas will be cleaned by more conventional means.

An additional environmental benefit of the Tampa project is that, instead of landfill wastes, the process produces sulfuric acid and solidified slag by-products that can be sold in the marketplace.

With new environmental standards in effect in 2000, utilities will be looking for the cleanest, most efficient power technologies available. The Tampa Electric project will give utilities a technology that is:

  • Environmentally superior to older coal-based power generation technologies.

  • Capable of being installed in modules of varying outputs, sized to match power demands much more precisely than the much larger, traditional coal-fired boiler power stations.

  • Fuel-flexible, capable of using a wide variety of coals without impairing performance.

  • Economical, producing lower cost electricity to consumers, because of lower capital costs and higher generating efficiencies.

In addition to providing the base technology for new plants, the coal gasification technology can be installed in existing plants, where gasification equipment can be integrated with existing steam-generating facilities.

Throughout the United States, particularly in the Midwest and East, coal-fired utility boilers currently producing a total of over 95,000 megawatts will be more than 30 years old in 1996. Many of these aging plants are candidates for repowering, using the technology being demonstrated by Tampa Electric.

POWER magazine also presented awards this year to the Village of Robbins (IL) Resource Recovery Facility, which employs the Nation's first large-scale circulating fluidized bed boiler burning refuse-derived fuel, and the Birchwood Power Facility, a modern pulverized coal plant operating as an independent power producer in King George County, VA.

Previous Clean Coal Technology projects receiving POWER magazine awards include American Electric Power's Tidd Pressurized Fluidized Bed Combustion Project (1991), the Pure Air on the Lake Advanced Flue Gas Desulfurization Project (1993), Southern Company Service Inc.'s Innovative CT-121 Flue Gas Desulfurization Process (1994), and the repowered Wabash River Coal Gasification Power Plant (1996).

Tampa Electric's Polk Power Station has also received the Associated Building Contractors 1996 Excellence in Construction Award and the Southeastern Electric Exchange's 1996 Excellence in Engineering award.

It is one of 39 current projects in the DOE Clean Coal Technology Program, a joint government-industry program funded from 1985 to 1997. The $303 million Tampa Electric project is receiving $151 million from the Department of Energy with the remainder being provided by Tampa Electric Company and its industrial partners.

The Powerplant Awards are given annually by the editors of POWER to recognize "leadership in the application of fresh ideas, advanced technology and equipment designs, and creative business arrangements."

-End of TechLine-

For more information, contact:
Hattie Wolfe, Office of Fossil Energy, 202/586-6503 e-mail: hattie.wolfe@hq.doe.gov