Table of Contents Management Commitment Environmental Protection and Stewardship Environmental Compliance Pollution Prevention Partnerships and Public Involvement Innovation A Look to the Future	Responsibility guides TVA’s production of reliable power   As part of TVA’s hydro modernization process, an employee replaces a faulty bushing in a turbine at the agency’s Guntersville Hydropower Plant. Power production is something many people take for granted: flip a switch and the lights come on. But behind every electric outlet lies a complex system of power production facilities and the ecosystems in which they operate. These may seem like two very different systems, but in fact they’re not. In generating electric power, TVA treats them as a balanced, integrated whole. TVA derives power from an array of sources: hydropower dams, nuclear plants, combustion turbines, fossil plants, purchases from nearby utilities, and renewable resources like wind and sunlight. Of those, hydropower provided the Tennessee Valley with only about 9 billion kilowatt-hours of electricity last year. TVA is working to increase the efficiency of its hydro units, some of which still use equipment originally installed in the 1930s and 1940s. Click chart for raw data. In the early 1990s, the agency embarked on a massive modernization project that has produced a number of improvements in its facilities’ operation. During the past few years, for instance, TVA upgraded some of the dams’ complex mechanical controls by replacing bushings that required regular applications of lubricating grease with greaseless ones. Unfortunately, the new bushings proved unsatisfactory (they repeatedly caused friction and overheating, with subsequent outages), but they are being replaced with low-volume greased bushings that drastically reduce releases of grease into the river. Nuclear power furnishes a solid base of available energy—more than 46 billion kilowatt-hours in 2000—and TVA’s nuclear operations routinely set industry records for safety and performance. Last year, in fact, nuclear units run by TVA were ranked among the top 25 performers in the U.S. by Nucleonics Week, an industry trade publication. And although nuclear power has always aroused controversy, it helps to reduce the emissions caused by fossil-fuel combustion. In the U.S. alone, according to the Nuclear Energy Institute, nuclear power generation keeps 1.11 million metric tons (1.22 million tons) of nitrogen oxide and 2.16 million metric tons (2.38 million tons) of sulfur dioxide out of the air each year. Click chart for raw data. Coal-burning power plants provide most of the electricity generated by TVA—more than 95 billion kilowatt-hours in 2000, or 63 percent of the agency’s total power production. TVA knows its emissions contribute to the region’s air quality issues through the release of relatively large quantities of sulfur dioxide (SO2) and nitrogen oxide (NOx). That’s why the agency has taken a number of steps—some exceeding those required by law—to improve the performance of its fossil plants and to lower emissions. Reducing emissions January 1, 2000, marked the beginning of Phase II of the Environmental Protection Agency’s acid-rain program, which is designed to reduce SO2 and NOx emissions nationwide by 9 million metric tons and 1.8 million metric tons (10 million tons and 2 million tons) from 1980 levels, respectively. Although TVA’s fossil plants generated 6 percent more electricity in 2000 than in 1999, the agency succeeded in reducing its SO2 emissions by more than 6 percent and its NOx emissions by 20 percent. The SO2 reduction figure, however, did not meet TVA’s target due to timing and delays related to planned low-sulfur fuel switches, which underscores the need to continue to improve performance in this area. Click chart for raw data. TVA’s most significant effort to reduce fossil-plant emissions in 2000 was its installation of its first selective catalytic reduction (SCR) system at Paradise Fossil Plant in Kentucky. An SCR system removes NOx by directing a plant’s flue gas into an ammonia-injection reactor. In the presence of a catalyst, the ammonia reacts with the NOx in the gas to form harmless nitrogen gas and water vapor. TVA did have to overcome several start-up and operational problems with its first SCR, one of which was an improper sizing for an ammonia vaporizing system. Using the experience it gained at Paradise, the agency is now set to spend an estimated $850 million on the installation of 17 more SCRs by the spring of 2005, with the goal of reducing NOx emissions during the summer ozone season by 70 to 75 percent. This step comes in addition to TVA’s introduction of low-NOx burners, overfire air controls, and boiler-optimization controls, which are decreasing NOx emissions at other fossil plants across the Valley. Click chart for raw data. 1999 and 2000 figures reflect increases in fossil-power and combustion-turbine generation.   Click chart for raw data.   In addition to installing limestone scrubbers at three plants, TVA continued to reduce SO2 emissions by burning low-sulfur coal. Occasionally the coal was co-fired, or burned simultaneously, with natural biomass materials to lower SO2 emissions even farther. Eight new oil- or natural-gas-fired combustion turbines were installed last year, and 20 others were modified to burn natural gas, which improves efficiency, reduces SO2 and other emissions, and plays an important part in meeting the Valley’s growing demand for power. TVA will install eight additional turbines by the summer of 2001 to ensure that it can continue to supply the power needed during peak periods while working toward its SO2-reduction goals. Unfortunately, the release of CO2, a substance that is considered to contribute to global warming, remains relatively unchecked. There are currently no commercially viable retrofit technologies available to lessen the release of CO2, and TVA anticipates that its CO2 emissions will continue to rise in coming years as demand for power increases. Power production is a big job. But TVA makes a concerted effort to ensure that the environmental impact of its operations remains as small as possible.		Stay Connected Thanks to the solar power array at Gibson County High School in Dyer, Tennessee, students and teachers are learning firsthand about energy produced by photovoltaic modules. TVA strives to find new uses for the by-products of fossil generation. Find out how waste materials become environmentally friendly products. Warming Up to Green Power TVA uses wind and solar power as renewable sources of energy and will soon add landfill gas. Keeping Clean Through Energy Conservation Several TVA programs encourage wise energy use, an important part of pollution prevention.   “Cormetech is pleased to play a role in helping TVA improve the Tennessee Valley’s bigger environmental picture—a picture in which the power needed to keep our communities and our businesses humming is generated in an environmentally sensitive manner. The catalysts we produce for TVA’s selective catalytic reduction systems not only help provide high-quality jobs in the Valley but also contribute to a cleaner environment here.” —Fred Maurer, President and CEO, Cormetech
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