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Методичка ч.2 3610 для beginners .doc
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Text 2 Modern biomass

Biomass simply means fuel produced from organic sources. Traditional biomass such as wood, charcoal, and other plant matters has been fuel of choice for thousand years, and it remains so in many parts of the world. Modern biomass, however includes other types of fuel derived from plants, such as the residuals of existing agricultural, lifestock and lumber industry, from forests planted and harvested renewably, and from farms dedicated to this purpose, from the processing of pulpwood residues, cereals and logging operations, which can be processed into gas or burned in bio gas power plants to generate electricity. Methane from urban landfills and from animal and human wastes is another potential type of fuel derived from biomass. Modern biomass may have the greatest potential for growth, especially in transportation and powering vehicles. For example, Brazil has been a leading nation in the use of ethanol (alcohol-based fuel) for automobiles. It is derived from sugar cane and grains grown specially to produce ethanol. Biomass also looks promising as a fuel source for electricity in small, local power stations.

Answer the following questions:

  1. What is biomass?

  2. What does modern biomass include?

  3. Can methane be derived? How?

  4. Does biomass have potential for growth?

  5. What country has been a leading nation in the use of ethanol (alcohol-based fuel) for automobiles?

Text 3 Wind

The use of wind energy is growing faster then any other type of renewable energy because of improvements in the wind turbine technology over the past 30 years. The best locations for wind as an energy source are coasts, mountains, and plains. Like solar rays, wind is also a form of intermittent renewable energy, available only about 30 % of the time. Often when the sun isn’t shining, the wind is blowing; so many users rely on wind turbines to complement solar panels. Most of the world's wind generation capacity is located in the United States, Denmark (the pioneer in wind generation), the Netherlands (famous for its use of windmills), Germany, and India. While wind generation of electricity is clean, some disadvantages include the noise of blades of windmills and the appearance. A large wind farm on a hillside is clearly visible, in the same way that large arrays of solar panels are.

Answer the following questions:

  1. Why is the use of wind energy growing faster than any other type of renewable energy?

  2. Where can we locate

  3. Is wind a form of intermittent renewable energy?

  4. Why do many users rely on turbines?

  5. Where is most of the world's wind generation capacity located?

  6. What are the disadvantages of the use of wind energy?

Text 3 Other types of power plants

3.1 Steam Turbine Plants

Steam turbine plants can be divided into three general categories: fossil fueled, nuclear, and renewable. Most of electricity produced in the United States, for example, comes from fossil fuel steam turbine plants, about 70%. The dominant fossil fuels are coal, petroleum and natural gas; others include petroleum coke, coke oven gas, and liquefied petroleum gas. Steam turbine plants operate by burning fuel, which heats water in a boiler; the water boils and produce steam, which is channeled to a turbine and turns it. The turbine is connected to a generator shaft which turns and produces power. All steam turbine plants function the same way.

Of the many fuels used in steam turbine plants, coal is the most common. Coal is inexpensive and readily available since the US has large deposits. Annually electric utilities purchase over 900 million short tons (короткая\малая тонна = 907,2 кг) of coal for electric generation.

Answer the following questions:

  1. What three categories can steam turbine plants be divided into?

  2. What are the dominant fossil fuels?

  3. How do steam turbine plants operate?

  4. What are the pros and cons of building steam turbine plants?