Electric energy units

Watthour (Wh) An electrical energy unit equal to one watt of power supplied to, or taken from, an electric circuit steadily for one hour. 

Taking into account the purification losses, the following operating requirements are necessary in order to obtain 100 kg of purified acetylene 200 kg hydrocarbons (feedstock plus quench), 1030 kWh electric energy for the arc, 250 kWh electric energy for the separation unit, and 150 kg steam. 

Clinker production requires large quantities of fuel. In the United States, coal (qv) and natural gas are the most widely used kiln fuels but fuels derived from waste materials, eg, tires, solvents, etc, are increasing in importance (53) (see Fuels fromwaste Gas,natural). In addition to the kiln fuel, electrical energy is required to power the equipment. This energy, however, amounts to only about one-ninth that of the kiln fuel. The cement industry carefully considers all measures that can reduce fuel demand. 

Canada, in response to extreme concerns regarding the reliability of the rapidly developing interconnected power networks in North America. NERC is a not-for-profit corporation owned by ten regional councils, whose members come from virtually all segments of the electric power industiy. Their parent companies account for virtually all the electrical energy supplied thronghout the United States, Canada, and northern portions of Baja California, Mexico. The various regional councils arc as follows ... 

The bulk system has long been seen as a vital element in the maintenance of an economic and reliable supply of electrical energy in North America, and a high degree of redundancy has been incorporated to achieve this objective. The North American Electric Reliability Council (NERC) was formed in 1968, following the November 9-10, 1965, blackout that affected the northeastern United States and Ontario,... 

The North American electric power transmission system has been described as the largest, most complex machine ever built by humanity. It is a massive network of generating stations, transmission lines, substations, distribution lines, motors, and other electrical loads all interdependently linked for the conversion, transportation, and control of electrical energy. Approximately 60 percent of all energy utilized in the United States passes through the interconnected electric power system. The major goal of the system is to most efficiently and reliably deliver electric power from generating stations to residential, commercial, and industrial consumers. 

About 8(1 percent of the electric energy used in the United States is derived from stored energy in coal. The stored energy has its origin in photosynthesis. Coal is the end product of the accumulation of plant matter in an oxygen-deficient environment where burning is thwarted. Formation takes millions of years. Proven reseiwes of coal in the United States are upwards of 500 billion tons, a reserve so great that even if coal continues to be burned at a rate of over one billion tons per year, the reserves will last for hundreds of years. 

Throughout this text, we will use the SI unit joule (J)> defined in Appendix 1, to express energy. A joule is a rather small quantity. One joule of electrical energy would keep a 10-W lightbulb burning for only a tenth of a second. For that reason, we will often express energies in kilojoules (1 kj = 103 J). The quantity h appearing in Planck s equation is referred to as Planck s constant... 

Your electric bill deals with a different unit of electrical energy called the kilowatt hour (kWh). The joule and the kilowatt hour are related through a simple conversion factor ... 

In equations containing terms relating to electrical energy, EF, and terms relating to heat absorbed, Qc, we must not forget that both are to be measured in the same units. If E is in volts, and F in coulombs ... 

The total energy of a fluid in motion is made up of a number of components. For unit mass of fluid and neglecting changes in magnetic and electrical energy, the magnitutes of the various forms of energy are as follows. 

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