ТОР 5 статей:
More than one-third of the primary energy in the Nation is used to generate electricity. Consumers expect electricity to be instantly available; that is, at the flick of a switch. In fact, electricity is so important to the functioning of our society that its unavailability is newsworthy. The U. S. electric power industry is organized to ensure that an adequate supply of electricity is available to meet all requirements, both now and in the future. This section provides a discussion on the capability of the electric power industry to meet that demand and the various methods used within the U. S. industry for converting energy into electricity.
The rating of a generator (that is, its nameplate capacity) is a measure of its ability to produce electricity. Nameplate capacity is the full-load continuous rating of the generator under specified conditions, as designated by the manufacturer, and is usually indicated on a metal plate attached to the generator. The capability of the generating unit in the summer is generally less than in the winter due to high ambient-air and cooling-water temperatures, which cause generating units to be less efficient.
Electric utilities use a variety of prime movers based on the loads, availability of fuels, and energy requirements of the utility. The most common prime movers are:
steam turbine, internal-combustion engine, gas combustion turbine, water turbine, and wind turbine.
A turbine converts the kinetic energy of a moving fluid (liquid or gas) to mechanical energy. Turbines have a series of blades mounted on a shaft against which fluids are forced, thus rotating the shaft connected to the generator. The fluids most commonly used in turbines are steam, hot air, or combustion products, and water.
Most prime movers used to produce electricity today are turbines. The energy sources most often used with prime movers are the fossil fuels: coal, petroleum, and natural gas.
Задание 3. Найдите в тексте слово по его определению:
1)to bring into existence, to produce;
2) a machine or motor driven by a wheel which is turned by a current of water, steam, air or gas;
3) to change from one thing into another;
4) caused, operated or produced by machinery;
5) the amount that something can produce;
6) force that may be used for doing work, driving a machine, or producing electricity.
Задание 4. Дайте определения следующим словам:
Electricity, supply, engine, to indicate, load.
Задание 5. Задайте вопросы к следующим предложениям:
1. The U. S. electric power industry is organized to ensure that an adequate supply of electricity is available to meet all requirements.
2. The capability of the generating unit in the summer is generally less than in the winter.
3. Electric utilities use a variety of prime movers.
4. A turbine converts the kinetic energy of a moving fluid (liquid or gas) to mechanical energy.