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Origins of Electric Power. Lightning: The First Power Source. Cannot be used commercially unless someone can figure out away to store a 100,000,000 volts in a few microseconds.
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Lightning: The First Power Source • Cannot be used commercially unless someone can figure out away to store a 100,000,000 volts in a few microseconds. • Most energy in a lightning strike is converted to heat, sound, and light energy, so there is little left to capture and store.
Origin of usable Electric Power • The first water turbine were used on August 26th, 1895 at Niagara Falls, • The power generated was used to manufacture aluminum and carborundum, • The following year, Buffalo, New York became the first city to receive power from Niagara Falls. • This power was used to power street lights and street cars,
Origin of usable Electric Power • The first practical widespread use of electric power was the telegraph. • The first telegraph’s used batteries to produce electric current, • This current traveled via wires over substantial distances, • electromagnets produced an effect at one end when a switch was closed at the other. • By using magnets with many windings telegraphs were able to operate with low electric currents. • This was important because the long conducting wire had an appreciable resistance to the flow of the current, resulting in lost energy.
Emergence of Electric Utilities in America • The modern electric utility industry in the United States can be traced to the invention of the practical light bulb in 1879 by Thomas Alva Edison. • Always looking toward the marketplace, Edison realized that his light bulb would mean nothing unless he developed an entire electric power system that generated and distributed electricity. • By 1882, he had developed such a system, and he installed the world's first central generating plant on Pearl Street in New York City's financial district.
“Transmission” of Electrical Power • Electric power transmission is the bulk transfer of electrical energy; • the first step in the delivery of electricity to consumers. • Transmission moves electrical power over long distances.
Simplified Diagram of AC Electricity Distribution from Generation Stations to Consumers
Transmission, cont… • Electric power transmission allows distant energy sources (such as hydroelectric power plants) to be connected to consumers in population centers. • Power is usually transmitted as alternating current (AC) through overhead power lines. • Underground power transmission is rarely used because of its higher cost of installation and maintenance, compared to overhead wires, as well as the difficulty of voltage control on long cables.
Transmission, cont… • Electricity is transmitted at high voltages (110 kV or above) to reduce energy loss during transmission. • Lower voltages such as 66 kV and 33 kV are usually considered sub-transmission voltages but are occasionally used on long lines with light loads. • Voltages less than 33 kV are usually used for distribution. • Voltages above 230 kV are considered extra-high voltage and require different equipment designs compared to that used at lower voltages.
“Distribution” of Electrical Power • In the early days of commercial use of electric power, the transmission of electric power was at the same voltage as used by lighting and mechanical devices, • This restricted the distance between generating plants and consumers.
Distribution, cont… • Then came the “Universal System”, • Regarded as one of the most influential innovations for the use of electricity, the "universal system" uses transformers to step-up voltage from generators to high-voltage transmission lines, and then to step-down voltage to local distribution circuits or industrial customers.
Distribution, cont… • Electricity travels at nearly the speed of light, arriving at a destination at almost the same moment it is produced. • Unlike oil or natural gas in a pipeline, electricity cannot be easily stored. • It must be generated and delivered at the precise moment it is needed.
Distribution, cont… • Distribution is the final stage in the delivery of electricity to end users. • A distribution system's network carries electricity from the transmission system and delivers it to consumers. • Typically, networks include: • medium-voltage (less than 50 kV) power lines, • electrical substations and • pole-mounted transformers, • low-voltage (less than 1 kV) distribution wiring, and • electricity meters.
Distribution, cont… Example of a Typical Residential Service Line • Power distribution line • Grounding line • Step-down transformer • Service line to house
The Power “Grid” • A power transmission network is referred to as a "grid". • Multiple redundant lines between points on the network are provided so that power can be routed from any power plant to any load center. • Much analysis is done by transmission companies to determine the maximum reliable capacity of each line,
The Grid, cont… • Transmission Grid “Inputs” • At the generating plants the energy is produced at a relatively low voltage between about 2300 volts and 30,000 volts, depending on the size of the unit. • The generator terminal voltage is then stepped up by the power station transformer to a higher voltage (115 kV to 765 kV AC, varying by country) for transmission over long distances. • Transmission Grid “Exit Points” • At substations, transformers reduce the voltage to a lower level for distribution to commercial and residential users. • This distribution is accomplished with a combination of sub-transmission (33 kV to 115 kV, varying by country and customer requirements) and distribution (3.3 to 25 kV). • At the point of use, the energy is transformed to low voltage (100 to 600 V, varying by country and customer requirements).
The “Smart Grid” • Many experts have been calling for power companies to create a “Smart Grid”, • A smart grid is an electric distribution system that leverages computer technology: software, sensors at power plants, and power-line improvements to increase the efficiency of the transmission of power from the producer, • Smart Grids can make it easier for consumers to cut their energy use. • Energy policymakers have talked for years about the need to upgrade the country’s transmission grid to make it both more reliable and more efficient to cut down energy loss in distribution.
Where is the Smart Grid? • In early October, 2009, Energy Secretary Steven Chu warned that China is ahead of the United States in the development of “smart grid” technologies. • The Energy Department announced it would spend $100 million to train workers to upgrade the electric transmission system. • New worker-training programs will be paid for by federal stimulus money. • Chu also announced a related $44 million program for state public utility commissions to encourage more local smart grid efforts.
Smart Grid, cont… • Improving the grid is central to another goal: expanding renewable energy usage. • Renewable energy availability is intermittent, which makes it much tougher for utility engineers to ensure electricity is available where it is needed. • Even windy areas have calm days and sunny regions can be cloud-covered from time to time. • Like most matters involving energy, transmission of electricity is a political issue. • Controlling who builds transmission lines involves state versus federal rights and has been a difficult issue for Congress. • Electric Companies often buck at government efficiency standards due to cost concerns.
Smart Grid, cont… • Along with developing a Smart Grid, Alternative Energy is another method that would eliminate some of the load on the current Electric Grid, • But, the United States is already behind in the development an implementation of Alternative Energies, • Solar photovoltaics, manufacturing of hybrid vehicle batteries, energy efficiency, and nuclear power are all options that many countries have already implemented. • The U.S. is also trailing on developing high-voltage transmission lines; • China is currently developing 800-kilovolt (kV) direct current lines and is researching a 1- million-kilovolt direct current line. • Chu said "They (China) are ahead of the rest of the world right now,” • and he added, "We are the pioneers. But, We are not the leaders."
So How do we develop Alternative Energies? We develop and implement Smart Grid Technologies!
Net-Zero Energy Buildings • Produce as much energy and power as they use. • And many times, they produce more power and energy than they use, and in doing so, if connected to the grid with “Net Energy Metering,” the meters reverse and the building or home owner receives one or more credits for the power supplied to the grid.
Net-Zero, cont… • Solar Tri-generationis defined as the simultaneous generation of cooling, heating, and power (i.e., electricity) with only the free solar energy from the sun providing the "fuel". • Eco-generation refers to a power and energy system that uses the “natural” energy or fuel that is available for a specific site or location (e.g., solar, wind, biomethane, geothermal, and ocean power, including ocean tidal and ocean thermal energy conversion.)
Electric Car-to-Grid Communications • Ford has developed an onboard device for car owners to program when and for how long to charge their cars. • Consumers would program the charging via an onboard touch screen. They could even decide whether to charge their cars only when renewable power is available over the grid.
Car-to-Grid, cont… • The car's computer would send charging instructions to the grid via advanced electric meters (smart meters) provide by the utilities. • Ford has received about $100 million in grants from the U.S. DOE, of which $30 million will be used for vehicle demonstration and grid integration.
Smart Meters • Unlike the conventional meters that have been around for decades, this new breed of meter comes with sensors and wireless communications abilities that enable it to report each customer's energy consumption in real-time and to alert utilities of any equipment problems. • Smart meters transmit their data back to headquarters, without the aid of a meter reader, and can be used, with a customer’s permission, to remotely manipulate energy-using devices like air conditioners.
Smart Meters, cont… • That, of course, requires pricing power by the hour. • Another function would be telling customers, hour by hour, what the price of electricity is, thus giving homeowners or business owners the ability to limit use during peak periods, when power is more pricey.
Smart Meters, cont… • Current technology would allow a standard communications protocol so that the grid and appliances could talk to each other. • Thus, a smart grid would allow an electric system to absorb more intermittent power sources, like wind and sun, and stay balanced, by shedding load as required. • Simply having detailed information about use and price would lead many consumers to shut off devices they are not using.
Threats to the Power Grid Cyber-Warfare • The Federal government admits the power grid is susceptible to cyber-warfare. • Massive power outages caused by a cyber attack would cause a crisis making it difficult for government and emergency workers to respond to critical concerns. • The U.S. Department of Homeland Security works with industry to identify vulnerabilities and to help industry enhance the security of control system networks. • The federal government is also working to ensure that security is built into the next generation of “smart grid” networks.
Credits Dr. Richard J. Fogg Associate Vice President Institutional Advancement Manhattan Area Technical College Manhattan, Kansas Dr. James Barger Department Chair, Pre-Engineering Landstown High School and Technology Academy Virginia Beach, Virginia
