Units, fossil-fueled generating

Table IV. Projected Mix of Fossil-Fueled Generating Units...

Maintenance cost savings and increased plant availability at fossil fuel generating units... 

If possible comparisons are focused on energy systems, nuclear power safety is also estimated to be superior to all electricity generation methods except for natural gas (30). Figure 3 is a plot of that comparison in terms of estimated total deaths to workers and the pubHc and includes deaths associated with secondary processes in the entire fuel cycle. The poorer safety record of the alternatives to nuclear power can be attributed to fataUties in transportation, where comparatively enormous amounts of fossil fuel transport are involved. Continuous or daily refueling of fossil fuel plants is required as compared to refueling a nuclear plant from a few tmckloads only once over a period of one to two years. This disadvantage appHes to solar and wind as well because of the necessary assumption that their backup power in periods of no or Httie wind or sun is from fossil-fuel generation. Now death or serious injury has resulted from radiation exposure from commercial nuclear power plants in the United States (31). 

In 1985, about 70% of the sulphur dioxide in the United States was emitted from fossil-fueled generating stations while in Canada, about 50% was... 

Autonomous power systems can be based on renewable energy (RE) units, such as wind turbines, photovoltaic systems or small hydro power stations and fossil-fuel generators. Due to the intermittent nature of renewable energy, storage devices and/or appropriate demand management strategies are necessary when conventional generators are not included in the system. 

This shows that all these systems have already left the experimental R D stage and become an economic reality. They have already demonstrated lower consumption of natural fossil fuels per unit of power generated and lower emission of greenhouse gases and other harmful products. Other advantages over thermal power plants are associated with fuel cell-based power plants. They can be produced in modules, from which power plants of different size and output can be put together. This attribute, known as scalability, facilitates the design and construction of plants adapted to specific local requirements. 

This shows that all these systems have already left the experimental R D stage and became an economic reality. They have already demonstrated lower consumption of natural fossil fuels per unit of power generated and lower emission of greenhouse gases and other harmful products. 

At the turn of the century, nearly 70 percent of U.S. fossil fuel plants (43 percent of fossil fuel generation capacity in the United States) will be more than 30 years old, with many critical plants approaching the end of their nominal design life. Utilities are often planning to extend the service life of these plants even further, possibly even imder more severe operating conditions. 

Nuclear Reactors. Nuclear power faciUties account for about 20% of the power generated in the United States. Although no new plants are plaimed in the United States, many other countries, particularly those that would otherwise rely heavily on imported fuel, continue to increase their nuclear plant generation capacity. Many industry observers predict that nuclear power may become more attractive in future years as the price of fossil fuels continues to rise and environmental regulations become more stringent. In addition, advanced passive-safety reactor designs may help allay concerns over potential safety issues. 

Table 1. Estimated Emissions from Fossil-Fueled Steam-Electric Generating Units at U.S. Electric Utilities, 10 t ...

Fossil-Fuel-Fired Steam Generators for Which Construction Commenced after August 17, 1971 Electric Utility Steam Generating Units for Which Construction Commenced after September 18, 1978... 

Many dozens of industrialized countries now employ nuclear reactors for power generation, and some countries produce more electrical power by nuclear reaction than by fossil fuel combustion (France is an example). The United States, however, has the largest installed capacity of nuclear-powered boiler plants (in the year 2000 there are more than 120 nuclear reactor power plants in the United States). Nuclear power is also widely used for marine duty in both commercial and naval vessels. 

In the United States, methane is a major energy source used in many homes for cooking and heating of water and indoor air and water. It is commonly known that some power plants and industries use natural gas as a source of energy for generation of electricity and process heat and that this methane is a fossil fuel obtained from gas wells and transmitted throughout the country by gas pipelines. Most people also know that methane bubbles up from polluted swamps where sedimented plant matter is undergoing decomposition. Because of odors from swamps, and the odor due to natural gas additives, methane is incorrectly considered malodorous. 

It is therefore vital that the United States in particular and all developed countries, emphasize nuclear power in meeting electric power needs, and to the extent possible substitute uranium for fossil fuel. It is equally critical that, as aging nuclearfiacilities are taken out of commission, replacement power generation be nuclear and not fossil fuel. 

Long-range atmospheric transport of Hg from fossil fuel combustion and solid waste incineration has increased Hg in freshwater and biota. In the United States, combustion of fossil fuels for power generation is estimated to generate about 30% of the total release of Hg into the atmosphere (Harriss and Hohenemser, 1978). One in every three lakes in the United States and nearly one-quarter of the nation s rivers contain various pollutants, including Hg (CNN, 2004). Forty States in the U.S. have issued advisories for methylmercury on selected water-bodies, and 13 states have statewide advisories for some or all sportfish from rivers or lakes (USGS, 2000). Fish consumption advisories for methylmercury account for more than three-quarters of all fish consumption advisories. 

The primary advantage of nuclear energy is that enormous amounts of energy are liberated per unit mass of fuel. Also, the air pollution (oxides of S, N, C and particulate matter) caused by fossil fuel electric power plants is not a problem with nuclear energy plants. In European countries, where fossil fuel reserves are scarce, most of the electricity is generated by nuclear power plants for these reasons. 

There are several initiatives for the development and demonstration of CCS worldwide. For instance, the European Union has an ambition to deploy 10-12 full-scale CCS demonstration projects within Europe by 2015, testing various ways of integrating CCS in coal and gas-fired power generation it also aims for CCS to be commercially viable for all new fossil fuel power plants by 2020, with existing plants progressively retrofitted (EC, 2007). Other pilot and demonstration plants are planned in the United States, Australia and China.5... 

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