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128-640: The Texas Interconnection is an alternating current (AC) power grid – a wide area synchronous grid – that covers most of the state of Texas . The grid is managed by the Electric Reliability Council of Texas (ERCOT) . The Texas Interconnection is one of the three minor grids in the North American power transmission grid . The other two minor interconnections are the Quebec Interconnection and

256-403: A balanced signaling system, so that the two wires carry equal but opposite currents. Each wire in a twisted pair radiates a signal, but it is effectively cancelled by radiation from the other wire, resulting in almost no radiation loss. Coaxial cables are commonly used at audio frequencies and above for convenience. A coaxial cable has a conductive wire inside a conductive tube, separated by

384-448: A dielectric layer. The current flowing on the surface of the inner conductor is equal and opposite to the current flowing on the inner surface of the outer tube. The electromagnetic field is thus completely contained within the tube, and (ideally) no energy is lost to radiation or coupling outside the tube. Coaxial cables have acceptably small losses for frequencies up to about 5 GHz. For microwave frequencies greater than 5 GHz,

512-477: A power plant , energy is generated at a convenient voltage for the design of a generator , and then stepped up to a high voltage for transmission. Near the loads, the transmission voltage is stepped down to the voltages used by equipment. Consumer voltages vary somewhat depending on the country and size of load, but generally motors and lighting are built to use up to a few hundred volts between phases. The voltage delivered to equipment such as lighting and motor loads

640-480: A "fundamental transition" of the world's energy markets towards renewables, according to a report released by REN21 , a global renewable energy policy network based in Paris. In 2010, renewable power consisted about a third of the newly built power generation capacities. By the end of 2011, total renewable power capacity worldwide exceeded 1,360 GW, up 8%. Renewables producing electricity accounted for almost half of

768-810: A 22.5% increase on the 158,700 MW installed at the end of 2009. The increase for 2010 represents investments totalling €47.3 billion (US$ 65 billion) and for the first time more than half of all new wind power was added outside of the traditional markets of Europe and North America, mainly driven, by the continuing boom in China which accounted for nearly half of all of the installations at 16,500 MW. China now has 42,300 MW of wind power installed. Wind power accounts for approximately 19% of electricity generated in Denmark , 9% in Spain and Portugal , and 6% in Germany and

896-440: A compromise between low frequency for traction and heavy induction motors, while still allowing incandescent lighting to operate (although with noticeable flicker). Most of the 25 Hz residential and commercial customers for Niagara Falls power were converted to 60 Hz by the late 1950s, although some 25 Hz industrial customers still existed as of the start of the 21st century. 16.7 Hz power (formerly 16 2/3 Hz)

1024-550: A controlled flow of energy while also functionally isolating the independent AC frequencies of each side. The Texas Interconnection is tied to the Eastern Interconnection with a 220 MW DC tie near Oklaunion , and a 600 MW DC tie near Monticello , and is tied to NERC ( North American Electric Reliability Corporation ) systems in Mexico with a 300 MW DC tie near McAllen , and a 100 MW VFT tie near Laredo . There

1152-490: A direct current does not create electromagnetic waves. At very high frequencies, the current no longer flows in the wire, but effectively flows on the surface of the wire, within a thickness of a few skin depths . The skin depth is the thickness at which the current density is reduced by 63%. Even at relatively low frequencies used for power transmission (50 Hz – 60 Hz), non-uniform distribution of current still occurs in sufficiently thick conductors . For example,

1280-616: A fluid system to move the heat from the collector to its point of usage, and a reservoir or tank for heat storage. The systems may be used to heat domestic hot water, swimming pools, or homes and businesses. The heat can also be used for industrial process applications or as an energy input for other uses such as cooling equipment. In many warmer climates, a solar heating system can provide a very high percentage (50 to 75%) of domestic hot water energy. As of 2009 , China has 27 million rooftop solar water heaters. Photovoltaic (PV) cells, also called solar cells , convert light into electricity. In

1408-437: A form of dielectric waveguides, can be used. For such frequencies, the concepts of voltages and currents are no longer used. Alternating currents are accompanied (or caused) by alternating voltages. An AC voltage v can be described mathematically as a function of time by the following equation: where The peak-to-peak value of an AC voltage is defined as the difference between its positive peak and its negative peak. Since

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1536-459: A higher voltage requires less loss-producing current than for the same power at a lower voltage. Power is often transmitted at hundreds of kilovolts on pylons , and transformed down to tens of kilovolts to be transmitted on lower level lines, and finally transformed down to 100 V – 240 V for domestic use. High voltages have disadvantages, such as the increased insulation required, and generally increased difficulty in their safe handling. In

1664-636: A large share of the petroleum needed for domestic consumption, recently reached complete self-sufficiency in liquid fuels. Nearly all the gasoline sold in the United States today is mixed with 10 percent ethanol, a mix known as E10, and motor vehicle manufacturers already produce vehicles designed to run on much higher ethanol blends. Ford , DaimlerChrysler , and GM are among the automobile companies that sell flexible-fuel cars, trucks, and minivans that can use gasoline and ethanol blends ranging from pure gasoline up to 85% ethanol (E85). The challenge

1792-957: A lighting system where sets of induction coils were installed along a high voltage AC line. Instead of changing voltage, the primary windings transferred power to the secondary windings which were connected to one or several 'electric candles' (arc lamps) of his own design, used to keep the failure of one lamp from disabling the entire circuit. In 1878, the Ganz factory , Budapest, Hungary, began manufacturing equipment for electric lighting and, by 1883, had installed over fifty systems in Austria-Hungary . Their AC systems used arc and incandescent lamps, generators, and other equipment. Alternating current systems can use transformers to change voltage from low to high level and back, allowing generation and consumption at low voltages but transmission, possibly over great distances, at high voltage, with savings in

1920-490: A new high of US$ 329 Billion for global renewables investment. A key benefit that this investment growth brings is a growth in jobs. The top countries for investment in recent years were China, Germany, Spain, the United States, Italy, and Brazil. Renewable energy companies include BrightSource Energy , First Solar , Gamesa , GE Energy , Goldwind , Sinovel , Targray , Trina Solar , Vestas , and Yingli . Climate change concerns are also driving increasing growth in

2048-477: A new wind output record of nearly 19.7 GW at 7:19 pm, Central Standard Time. Wind power in Texas consists of over 40 wind farms , which together have a total nameplate capacity of over 30,000 MW, as of 2020. Texas produces the most wind power of any U.S. state and only a few countries exceed its installed capacity. According to ERCOT (Energy Reliability Council of Texas), wind power accounted for at least 15.7% of

2176-430: A number of sources and technologies at different stages of commercialization. The International Energy Agency (IEA) has defined three generations of renewable energy technologies, reaching back over 100 years: First-generation technologies are well established, second-generation technologies are entering markets, and third-generation technologies heavily depend on long-term research and development commitments, where

2304-404: A passion for the dedicated few to a major economic sector in countries such as Germany, Spain, the United States, and Japan. Many large industrial companies and financial institutions are involved and the challenge is to broaden the market base for continued growth worldwide. Solar heating systems are a well known second-generation technology and generally consist of solar thermal collectors ,

2432-607: A significant share of the total electricity supply, such as in the Philippines, where geothermal represented 17 percent of the total power mix at the end of 2008. Geothermal (ground source) heat pumps represented an estimated 30 GWth of installed capacity at the end of 2008, with other direct uses of geothermal heat (i.e., for space heating, agricultural drying and other uses) reaching an estimated 15 GWth. As of 2008 , at least 76 countries use direct geothermal energy in some form. Second-generation technologies have gone from being

2560-522: A single center-tapped transformer giving two live conductors, is a common distribution scheme for residential and small commercial buildings in North America. This arrangement is sometimes incorrectly referred to as "two phase". A similar method is used for a different reason on construction sites in the UK. Small power tools and lighting are supposed to be supplied by a local center-tapped transformer with

2688-555: A voltage of 55 V between each power conductor and earth. This significantly reduces the risk of electric shock in the event that one of the live conductors becomes exposed through an equipment fault whilst still allowing a reasonable voltage of 110 V between the two conductors for running the tools. A third wire , called the bond (or earth) wire, is often connected between non-current-carrying metal enclosures and earth ground. This conductor provides protection from electric shock due to accidental contact of circuit conductors with

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2816-403: A wire that is made of a non-perfect conductor (a conductor with finite, rather than infinite, electrical conductivity) pushes the alternating current, along with their associated electromagnetic fields, away from the wire's center. The phenomenon of alternating current being pushed away from the center of the conductor is called skin effect , and a direct current does not exhibit this effect, since

2944-470: Is 230 × R × W × 2 {\displaystyle 230\times R\times W\times 2} , that is 460 RW. During the course of one cycle (two cycle as the power) the voltage rises from zero to 325 V, the power from zero to 460 RW, and both falls through zero. Next, the voltage descends to reverse direction, -325 V, but the power ascends again to 460 RW, and both returns to zero. Alternating current

3072-530: Is called Litz wire . This measure helps to partially mitigate skin effect by forcing more equal current throughout the total cross section of the stranded conductors. Litz wire is used for making high-Q inductors , reducing losses in flexible conductors carrying very high currents at lower frequencies, and in the windings of devices carrying higher radio frequency current (up to hundreds of kilohertz), such as switch-mode power supplies and radio frequency transformers . As written above, an alternating current

3200-517: Is called a cycle ). In certain applications, like guitar amplifiers , different waveforms are used, such as triangular waves or square waves . Audio and radio signals carried on electrical wires are also examples of alternating current. These types of alternating current carry information such as sound (audio) or images (video) sometimes carried by modulation of an AC carrier signal. These currents typically alternate at higher frequencies than those used in power transmission. Electrical energy

3328-449: Is declining for wind power, solar photovoltaic (PV), concentrated solar power (CSP) and some biomass technologies. Renewable energy is also the most economic solution for new grid-connected capacity in areas with good resources. As the cost of renewable power falls, the scope of economically viable applications increases. Renewable technologies are now often the most economic solution for new generating capacity. Where "oil-fired generation

3456-410: Is dependent on regulated tariffs, due to high costs of infrastructure and ingredients for ongoing operations. Biomass does offer a ready disposal mechanism by burning municipal, agricultural, and industrial organic waste products. First-generation biomass technologies can be economically competitive, but may still require deployment support to overcome public acceptance and small-scale issues. As part of

3584-505: Is distributed as alternating current because AC voltage may be increased or decreased with a transformer . This allows the power to be transmitted through power lines efficiently at high voltage , which reduces the energy lost as heat due to resistance of the wire, and transformed to a lower, safer voltage for use. Use of a higher voltage leads to significantly more efficient transmission of power. The power losses ( P w {\displaystyle P_{\rm {w}}} ) in

3712-439: Is double of the one of the voltage's. To illustrate these concepts, consider a 230 V AC mains supply used in many countries around the world. It is so called because its root mean square value is 230 V. This means that the time-averaged power delivered P average {\displaystyle P_{\text{average}}} is equivalent to the power delivered by a DC voltage of 230 V. To determine

3840-495: Is growing faster than its fossil fuels and nuclear power capacity. Since 2005, production of solar cells in China has expanded 100-fold. As Chinese renewable manufacturing has grown, the costs of renewable energy technologies have dropped. Innovation has helped, but the main driver of reduced costs has been market expansion. See also renewable energy in the United States for US-figures. Renewable energy technologies are getting cheaper, through technological change and through

3968-469: Is highest in summer, primarily due to air conditioning use in homes and businesses. On July 19, 2018, consumer demand hit 73,259 MW. On Monday, August 12, 2019, a new peak of 74,820 MW was set between 4 p.m. and 5 p.m. Central Daylight Time (2200 GMT), as high temperatures in Houston hit 100 degrees Fahrenheit (38 °Celsius). ERCOT had more than 78,000 MW of generating capacity available to meet demand in

Texas Interconnection - Misplaced Pages Continue

4096-469: Is made of electric charge under periodic acceleration , which causes radiation of electromagnetic waves . Energy that is radiated is lost. Depending on the frequency, different techniques are used to minimize the loss due to radiation. At frequencies up to about 1 GHz, pairs of wires are twisted together in a cable, forming a twisted pair . This reduces losses from electromagnetic radiation and inductive coupling . A twisted pair must be used with

4224-676: Is one AC tie switch in Dayton, Texas that has been used only once in its history, after Hurricane Ike . In October 2009, the Tres Amigas SuperStation was announced to connect the Eastern, Western, and Texas Interconnections via eight 5 GW superconductor links, but the Eastern Interconnection withdrew from the project in 2015, rendering the project moot. Construction was never started. In October 2024,

4352-521: Is probably by Guillaume Duchenne , inventor and developer of electrotherapy . In 1855, he announced that AC was superior to direct current for electrotherapeutic triggering of muscle contractions. Alternating current technology was developed further by the Hungarian Ganz Works company (1870s), and in the 1880s: Sebastian Ziani de Ferranti , Lucien Gaulard , and Galileo Ferraris . In 1876, Russian engineer Pavel Yablochkov invented

4480-446: Is standardized, with an allowable range of voltage over which equipment is expected to operate. Standard power utilization voltages and percentage tolerance vary in the different mains power systems found in the world. High-voltage direct-current (HVDC) electric power transmission systems have become more viable as technology has provided efficient means of changing the voltage of DC power. Transmission with high voltage direct current

4608-568: Is still used in some European rail systems, such as in Austria , Germany , Norway , Sweden and Switzerland . Off-shore, military, textile industry, marine, aircraft, and spacecraft applications sometimes use 400 Hz, for benefits of reduced weight of apparatus or higher motor speeds. Computer mainframe systems were often powered by 400 Hz or 415 Hz for benefits of ripple reduction while using smaller internal AC to DC conversion units. A direct current flows uniformly throughout

4736-498: Is the predominant power generation source (e.g. on islands, off-grid and in some countries) a lower-cost renewable solution almost always exists today". As of 2012, renewable power generation technologies accounted for around half of all new power generation capacity additions globally. In 2011, additions included 41 gigawatt (GW) of new wind power capacity, 30 GW of PV, 25 GW of hydro-electricity, 6 GW of biomass, 0.5 GW of CSP, and 0.1 GW of geothermal power. Renewable energy includes

4864-422: Is therefore V peak − ( − V peak ) = 2 V peak {\displaystyle V_{\text{peak}}-(-V_{\text{peak}})=2V_{\text{peak}}} . Below an AC waveform (with no DC component ) is assumed. The RMS voltage is the square root of the mean over one cycle of the square of the instantaneous voltage. The relationship between voltage and

4992-439: Is to expand the market for biofuels beyond the farm states where they have been most popular to date. The Energy Policy Act of 2005 , which calls for 7.5 billion US gallons (28,000,000 m ) of biofuels to be used annually by 2012, will also help to expand the market. The growing ethanol and biodiesel industries are providing jobs in plant construction, operations, and maintenance, mostly in rural communities. According to

5120-411: Is underpinning the renewable industry's rise and bringing the much needed transformation of our global energy system within reach." He added: "Renewable energies are expanding both in terms of investment, projects and geographical spread. In doing so, they are making an increasing contribution to combating climate change, countering energy poverty and energy insecurity". According to a 2011 projection by

5248-425: Is used to transmit information , as in the cases of telephone and cable television . Information signals are carried over a wide range of AC frequencies. POTS telephone signals have a frequency of about 3 kHz, close to the baseband audio frequency. Cable television and other cable-transmitted information currents may alternate at frequencies of tens to thousands of megahertz. These frequencies are similar to

Texas Interconnection - Misplaced Pages Continue

5376-618: The Alaska Interconnection . The two major interconnections are the Eastern Interconnection and the Western Interconnection . The Texas Interconnection is maintained as a separate grid for political, rather than technical reasons, but can draw some power from other grids using direct current DC ties . By not crossing state lines, the synchronous power grid is in most respects not subject to federal ( Federal Energy Regulatory Commission ) regulation. All of

5504-689: The Brazos Wind Farm . Solar power in Texas, along with wind power , has the potential to allow Texas to remain an energy-exporting state over the long term. The western portion of the state especially has abundant open land areas, with some of the greatest solar and wind potential in the United States. Development activities there are also encouraged by relatively simple permitting and significant available transmission capacity. Interconnections can be tied to each other via high-voltage direct current power transmission lines ( DC ties ), or with variable-frequency transformers (VFTs), which permit

5632-589: The February 13–17, 2021 North American winter storm caused large loss of coal, natural gas, wind, and nuclear power production, and a shortfall of over 10 gigawatts of customer demand, resulting in rolling blackouts across Texas affecting more than 4 million people. Although some wind turbines iced up, wind power produced more overall power than expected for this time of year. Millions of people were without power and water for numerous days, leading people to resort to boiling snow as their only water source. Officially,

5760-479: The International Energy Agency (IEA) has predicted that by 2025, renewable capacity will meet 35% of global power generation. Public policy and political leadership helps to "level the playing field" and drive the wider acceptance of renewable energy technologies. Countries such as Germany, Denmark, and Spain have led the way in implementing innovative policies which has driven most of

5888-1015: The PS10 solar power tower (Spain, 11 MW). The 370 MW Ivanpah Solar Power Facility , located in California's Mojave Desert , is the world's largest solar-thermal power plant project currently under construction. Many other plants are under construction or planned, mainly in Spain and the USA. In developing countries, three World Bank projects for integrated solar thermal/combined-cycle gas-turbine power plants in Egypt , Mexico , and Morocco have been approved. Global ethanol production for transport fuel tripled between 2000 and 2007 from 17 billion to more than 52 billion litres, while biodiesel expanded more than tenfold from less than 1 billion to almost 11 billion litres. Biofuels provide 1.8% of

6016-617: The Three Gorges Dam in China, Itaipu Dam across the Brazil/Paraguay border, and Guri Dam in Venezuela. The cost of hydroelectricity is low, making it a competitive source of renewable electricity. The average cost of electricity from a hydro plant larger than 10 megawatts is 3 to 5 U.S. cents per kilowatt-hour. Geothermal power plants can operate 24 hours per day, providing baseload capacity. Estimates for

6144-758: The U.S. Department of Energy announced a contract award of $ 360 million from the Bipartisan Infrastructure Law to help build Pattern Energy ’s Southern Spirit Transmission Project, a proposed 320-mile, 525-kV high voltage direct current line to connect the ERCOT grid with grids in the Southeast. If constructed, the line would provide three gigawatts of bidirectional capacity between Rusk County, Texas , and Choctaw County, Mississippi , and will use voltage source converter technology to enhance grid reliability—helping to mitigate disruptions like

6272-786: The Westinghouse Electric in Pittsburgh, Pennsylvania, on January 8, 1886. The new firm became active in developing alternating current (AC) electric infrastructure throughout the United States. The Edison Electric Light Company held an option on the US rights for the Ganz ZBD transformers, requiring Westinghouse to pursue alternative designs on the same principles. George Westinghouse had bought Gaulard and Gibbs' patents for $ 50,000 in February 1886. He assigned to William Stanley

6400-427: The food vs. fuel debate, several economists from Iowa State University found in 2008 "there is no evidence to disprove that the primary objective of biofuel policy is to support farm income." Hydroelectricity is the term referring to electricity generated by hydropower ; the production of electrical power through the use of the gravitational force of falling or flowing water. In 2015 hydropower generated 16.6% of

6528-543: The power crisis in the winter of 2021 . The project received final approval from the Federal Energy Regulatory Commission in May 2014. In February 2011, gas shortages and low temperatures led to 30 GW of capacity being unavailable and caused load shedding . There were prior severe cold weather events in 1983, 1989, 2003, 2006, 2008, and 2010. In February 2021, record low temperatures during

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6656-410: The 1980s and early 1990s, most photovoltaic modules were used to provide remote-area power supply , but from around 1995, industry efforts have focused increasingly on developing building integrated photovoltaics and photovoltaic power stations for grid connected applications. Many plants are integrated with agriculture and some use innovative tracking systems that follow the sun's daily path across

6784-492: The 208 GW of capacity added globally during 2011. Wind and solar photovoltaics (PV) accounted for almost 40% and 30%. Based on REN21 's 2014 report, renewables contributed 19 percent to our energy consumption and 22 percent to our electricity generation in 2012 and 2013, respectively. This energy consumption is divided as 9% coming from traditional biomass, 4.2% as heat energy (non-biomass), 3.8% hydro electricity and 2% electricity from wind, solar, geothermal, and biomass. During

6912-752: The AC system at the Grosvenor Gallery power station in 1886 for the London Electric Supply Corporation (LESCo) including alternators of his own design and open core transformer designs with serial connections for utilization loads - similar to Gaulard and Gibbs. In 1890, he designed their power station at Deptford and converted the Grosvenor Gallery station across the Thames into an electrical substation , showing

7040-486: The International Energy Agency, solar power plants may produce most of the world's electricity within 50 years, significantly reducing the emissions of greenhouse gases that harm the environment. The IEA has said: "Photovoltaic and solar-thermal plants may meet most of the world's demand for electricity by 2060 – and half of all energy needs – with wind, hydropower and biomass plants supplying much of

7168-646: The Renewable Fuels Association, "the ethanol industry created almost 154,000 U.S. jobs in 2005 alone, boosting household income by $ 5.7 billion. It also contributed about $ 3.5 billion in tax revenues at the local, state, and federal levels". Third-generation renewable energy technologies are still under development and include advanced biomass gasification , biorefinery technologies, hot-dry-rock geothermal power, and ocean energy . Third-generation technologies are not yet widely demonstrated or have limited commercialization. Many are on

7296-463: The Republic of Ireland. In Australian state of South Australia wind power, championed by Premier Mike Rann (2002–2011), now comprises 26% of the state's electricity generation, edging out coal fired power. At the end of 2011 South Australia, with 7.2% of Australia's population, had 54% of the nation's installed wind power capacity. Wind power's share of worldwide electricity usage at the end of 2014

7424-668: The United States. The wind boom in Texas was assisted by expansion of the state's Renewable Portfolio Standard , use of designated Competitive Renewable Energy Zones, expedited transmission construction, and the necessary Public Utility Commission rule-making. The Roscoe Wind Farm (781 MW), near the town of Roscoe, is the state's largest wind farm. Other large wind farms in Texas include: Horse Hollow Wind Energy Center , Sherbino Wind Farm , Capricorn Ridge Wind Farm , Sweetwater Wind Farm , Buffalo Gap Wind Farm , King Mountain Wind Farm , Desert Sky Wind Farm , Wildorado Wind Ranch , and

7552-401: The amount of wind energy in their portfolio, saying it is their cheapest option. Solar thermal power stations include the 354  megawatt (MW) Solar Energy Generating Systems power plant in the US, Solnova Solar Power Station (Spain, 150 MW), Andasol solar power station (Spain, 100 MW), Nevada Solar One (USA, 64 MW), PS20 solar power tower (Spain, 20 MW), and

7680-461: The benefits of mass production and market competition. A 2011 IEA report said: "A portfolio of renewable energy technologies is becoming cost-competitive in an increasingly broad range of circumstances, in some cases providing investment opportunities without the need for specific economic support," and added that "cost reductions in critical technologies, such as wind and solar, are set to continue." As of 2011 , there have been substantial reductions in

7808-413: The biggest difference being that waveguides have no inner conductor. Waveguides can have any arbitrary cross section, but rectangular cross sections are the most common. Because waveguides do not have an inner conductor to carry a return current, waveguides cannot deliver energy by means of an electric current , but rather by means of a guided electromagnetic field . Although surface currents do flow on

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7936-547: The city of Pomona, California , which was 14 miles away. Meanwhile, the possibility of transferring electrical power from a waterfall at a distance was explored at the Grängesberg mine in Sweden. A 45  m fall at Hällsjön, Smedjebackens kommun, where a small iron work had been located, was selected. In 1893, a three-phase 9.5  kv system was used to transfer 400 horsepower a distance of 15  km , becoming

8064-727: The competitive wholesale bulk-power market, and administers retail switching for 7 million premises in competitive choice areas. ERCOT is a membership-based 501(c)(4) nonprofit corporation, governed by a board of directors, and subject to oversight by the Public Utility Commission of Texas (PUC) and the Texas Legislature . ERCOT's members include consumers, electric cooperatives, generators, power marketers, retail electric providers, investor-owned electric utilities (transmission and distribution providers), and municipally owned electric utilities. Power demand

8192-507: The cost of conductors and energy losses. A bipolar open-core power transformer developed by Lucien Gaulard and John Dixon Gibbs was demonstrated in London in 1881, and attracted the interest of Westinghouse . They also exhibited the invention in Turin in 1884. However, these early induction coils with open magnetic circuits are inefficient at transferring power to loads . Until about 1880,

8320-443: The cost of solar and wind technologies: The price of PV modules per MW has fallen by 60 percent since the summer of 2008, according to Bloomberg New Energy Finance estimates, putting solar power for the first time on a competitive footing with the retail price of electricity in a number of sunny countries. Wind turbine prices have also fallen – by 18 percent per MW in the last two years – reflecting, as with solar, fierce competition in

8448-750: The country facing water shortages. Events at the Fukushima nuclear plant have renewed doubts about the ability to operate large numbers of nuclear plants safely over the long term. Further, cost estimates for "next generation" nuclear units continue to climb, and lenders are unwilling to finance these plants without taxpayer guarantees. The 2014 REN21 Global Status Report says that renewable energies are no longer just energy sources, but ways to address pressing social, political, economic and environmental problems: Today, renewables are seen not only as sources of energy, but also as tools to address many other pressing needs, including: improving energy security; reducing

8576-514: The cross-section of a homogeneous electrically conducting wire. An alternating current of any frequency is forced away from the wire's center, toward its outer surface. This is because an alternating current (which is the result of the acceleration of electric charge ) creates electromagnetic waves (a phenomenon known as electromagnetic radiation ). Electric conductors are not conducive to electromagnetic waves (a perfect electric conductor prohibits all electromagnetic waves within its boundary), so

8704-411: The cross-sectional area. A conductor's AC resistance is higher than its DC resistance, causing a higher energy loss due to ohmic heating (also called I R loss). For low to medium frequencies, conductors can be divided into stranded wires, each insulated from the others, with the relative positions of individual strands specially arranged within the conductor bundle. Wire constructed using this technique

8832-476: The design of electric motors, particularly for hoisting, crushing and rolling applications, and commutator-type traction motors for applications such as railways . However, low frequency also causes noticeable flicker in arc lamps and incandescent light bulbs . The use of lower frequencies also provided the advantage of lower transmission losses, which are proportional to frequency. The original Niagara Falls generators were built to produce 25 Hz power, as

8960-487: The development and use of such technologies. It is expected that renewable energy investments will pay off economically in the long term. EU member countries have shown support for ambitious renewable energy goals. In 2010, Eurobarometer polled the twenty-seven EU member states about the target "to increase the share of renewable energy in the EU by 20 percent by 2020". Most people in all twenty-seven countries either approved of

9088-472: The electric utilities in the Texas Interconnection are electrically tied together during normal system conditions and operate at a synchronous frequency of 60 Hz. The Electric Reliability Council of Texas (ERCOT) manages the flow of electric power on the Texas Interconnection that supplies power to 26 million Texas customers – representing 90 percent of the state's electric load. ERCOT is

9216-508: The electrical system to a safe state. All bond wires are bonded to ground at the main service panel, as is the neutral/identified conductor if present. The frequency of the electrical system varies by country and sometimes within a country; most electric power is generated at either 50 or 60  Hertz . Some countries have a mixture of 50 Hz and 60 Hz supplies, notably electricity power transmission in Japan . A low frequency eases

9344-464: The electricity generated in Texas in 2017, as wind was 17.4% of electricity generated in ERCOT, which manages 90% of Texas's power. The wind resource in many parts of Texas is very large. Farmers may lease their land to wind developers, creating a new revenue stream for the farm. The wind power industry has created over 24,000 jobs for local communities and for the state. Texas is seen as a profit-driven leader of renewable energy commercialization in

9472-522: The electromagnetic wave frequencies often used to transmit the same types of information over the air . The first alternator to produce alternating current was an electric generator based on Michael Faraday 's principles constructed by the French instrument maker Hippolyte Pixii in 1832. Pixii later added a commutator to his device to produce the (then) more commonly used direct current. The earliest recorded practical application of alternating current

9600-406: The energy supply portfolio, as they contribute to world energy security , reduce dependency on fossil fuels , and some also provide opportunities for mitigating greenhouse gases . Climate-disrupting fossil fuels are being replaced by clean, climate-stabilizing, non-depletable sources of energy: ...the transition from coal, oil, and gas to wind, solar, and geothermal energy is well under way. In

9728-414: The experiments; In their joint 1885 patent applications for novel transformers (later called ZBD transformers), they described two designs with closed magnetic circuits where copper windings were either wound around a ring core of iron wires or else surrounded by a core of iron wires. In both designs, the magnetic flux linking the primary and secondary windings traveled almost entirely within the confines of

9856-757: The first independent system operator (ISO) in the United States and one of nine ISOs in North America. ERCOT works with the Texas Reliability Entity (TRE), one of eight regional entities within the North American Electric Reliability Corporation (NERC) that coordinate to improve reliability of the bulk power grid. As the ISO for the region, ERCOT dispatches power on an electric grid that connects 46,500 miles of transmission lines and more than 550 generation units. ERCOT also performs financial settlements for

9984-479: The first commercial application. In 1893, Westinghouse built an alternating current system for the Chicago World Exposition . In 1893, Decker designed the first American commercial three-phase power plant using alternating current—the hydroelectric Mill Creek No. 1 Hydroelectric Plant near Redlands, California . Decker's design incorporated 10 kV three-phase transmission and established

10112-426: The five-years from the end of 2004 through 2009, worldwide renewable energy capacity grew at rates of 10–60 percent annually for many technologies, while actual production grew 1.2% overall. In 2011, UN under-secretary general Achim Steiner said: "The continuing growth in this core segment of the green economy is not happening by chance. The combination of government target-setting, policy support and stimulus funds

10240-446: The growth over the past decade. As of 2014, Germany has a commitment to the " Energiewende " transition to a sustainable energy economy, and Denmark has a commitment to 100% renewable energy by 2050. There are now 144 countries with renewable energy policy targets. Renewable energy continued its rapid growth in 2015, providing multiple benefits. There was a new record set for installed wind and photovoltaic capacity (64GW and 57GW) and

10368-480: The health and environmental impacts associated with fossil and nuclear energy; mitigating greenhouse gas emissions; improving educational opportunities; creating jobs; reducing poverty; and increasing gender equality... Renewables have entered the mainstream. In 2008 for the first time, more renewable energy than conventional power capacity was added in both the European Union and United States, demonstrating

10496-533: The horizon and may have potential comparable to other renewable energy technologies, but still depend on attracting sufficient attention and research and development funding. According to the International Energy Agency, cellulosic ethanol biorefineries could allow biofuels to play a much bigger role in the future than organizations such as the IEA previously thought. Cellulosic ethanol can be made from plant matter composed primarily of inedible cellulose fibers that form

10624-491: The human toll of the coal supply chain. New EPA initiatives targeting air toxics, coal ash, and effluent releases highlight the environmental impacts of coal and the cost of addressing them with control technologies. The use of fracking in natural gas exploration is coming under scrutiny, with evidence of groundwater contamination and greenhouse gas emissions. Concerns are increasing about the vast amounts of water used at coal-fired and nuclear power plants, particularly in regions of

10752-564: The inner walls of the waveguides, those surface currents do not carry power. Power is carried by the guided electromagnetic fields. The surface currents are set up by the guided electromagnetic fields and have the effect of keeping the fields inside the waveguide and preventing leakage of the fields to the space outside the waveguide. Waveguides have dimensions comparable to the wavelength of the alternating current to be transmitted, so they are feasible only at microwave frequencies. In addition to this mechanical feasibility, electrical resistance of

10880-511: The iron core, with no intentional path through air (see toroidal cores ). The new transformers were 3.4 times more efficient than the open-core bipolar devices of Gaulard and Gibbs. The Ganz factory in 1884 shipped the world's first five high-efficiency AC transformers. This first unit had been manufactured to the following specifications: 1,400 W, 40 Hz, 120:72 V, 11.6:19.4 A, ratio 1.67:1, one-phase, shell form. The ZBD patents included two other major interrelated innovations: one concerning

11008-481: The issue of whether biomass is carbon neutral is contested. Material directly combusted in cook stoves produces pollutants, leading to severe health and environmental consequences. Improved cook stove programs are alleviating some of these effects. The industry remained relatively stagnant over the decade to 2007, but demand for biomass (mostly wood) continues to grow in many developing countries , as well as Brazil and Germany . The economic viability of biomass

11136-625: The limitations of the direct current system. In 1886, the ZBD engineers designed the world's first power station that used AC generators to power a parallel-connected common electrical network, the steam-powered Rome-Cerchi power plant. The reliability of the AC technology received impetus after the Ganz Works electrified a large European metropolis: Rome in 1886. Building on the advancement of AC technology in Europe, George Westinghouse founded

11264-429: The losses (due mainly to the dielectric separating the inner and outer tubes being a non-ideal insulator) become too large, making waveguides a more efficient medium for transmitting energy. Coaxial cables often use a perforated dielectric layer to separate the inner and outer conductors in order to minimize the power dissipated by the dielectric. Waveguides are similar to coaxial cables, as both consist of tubes, with

11392-419: The lower speed is preferable for larger machines. If the load on a three-phase system is balanced equally among the phases, no current flows through the neutral point . Even in the worst-case unbalanced (linear) load, the neutral current will not exceed the highest of the phase currents. Non-linear loads (e.g. the switch-mode power supplies widely used) may require an oversized neutral bus and neutral conductor in

11520-484: The main street of Great Barrington. The spread of Westinghouse and other AC systems triggered a push back in late 1887 by Thomas Edison (a proponent of direct current), who attempted to discredit alternating current as too dangerous in a public campaign called the " war of the currents ". In 1888, alternating current systems gained further viability with introduction of a functional AC motor , something these systems had lacked up till then. The design, an induction motor ,

11648-538: The maximum value of sin ⁡ ( x ) {\displaystyle \sin(x)} is +1 and the minimum value is −1, an AC voltage swings between + V peak {\displaystyle +V_{\text{peak}}} and − V peak {\displaystyle -V_{\text{peak}}} . The peak-to-peak voltage, usually written as V pp {\displaystyle V_{\text{pp}}} or V P-P {\displaystyle V_{\text{P-P}}} ,

11776-469: The metal chassis of portable appliances and tools. Bonding all non-current-carrying metal parts into one complete system ensures there is always a low electrical impedance path to ground sufficient to carry any fault current for as long as it takes for the system to clear the fault. This low impedance path allows the maximum amount of fault current, causing the overcurrent protection device (breakers, fuses) to trip or burn out as quickly as possible, bringing

11904-425: The non-ideal metals forming the walls of the waveguide causes dissipation of power (surface currents flowing on lossy conductors dissipate power). At higher frequencies, the power lost to this dissipation becomes unacceptably large. At frequencies greater than 200 GHz, waveguide dimensions become impractically small, and the ohmic losses in the waveguide walls become large. Instead, fiber optics , which are

12032-596: The old economy, energy was produced by burning something — oil, coal, or natural gas — leading to the carbon emissions that have come to define our economy. The new energy economy harnesses the energy in wind, the energy coming from the sun, and heat from within the earth itself. In international public opinion surveys there is strong support for a variety of methods for addressing the problem of energy supply. These methods include promoting renewable sources such as solar power and wind power, requiring utilities to use more renewable energy, and providing tax incentives to encourage

12160-435: The paradigm for AC power transmission from a high voltage supply to a low voltage load was a series circuit. Open-core transformers with a ratio near 1:1 were connected with their primaries in series to allow use of a high voltage for transmission while presenting a low voltage to the lamps. The inherent flaw in this method was that turning off a single lamp (or other electric device) affected the voltage supplied to all others on

12288-431: The peak voltage (amplitude), we can rearrange the above equation to: For 230 V AC, the peak voltage V peak {\displaystyle V_{\text{peak}}} is therefore 230  V × 2 {\displaystyle 230{\text{ V}}\times {\sqrt {2}}} , which is about 325 V, and the peak power P peak {\displaystyle P_{\text{peak}}}

12416-610: The power delivered is: where R {\displaystyle R} represents a load resistance. Rather than using instantaneous power, p ( t ) {\displaystyle p(t)} , it is more practical to use a time-averaged power (where the averaging is performed over any integer number of cycles). Therefore, AC voltage is often expressed as a root mean square (RMS) value, written as V rms {\displaystyle V_{\text{rms}}} , because For this reason, AC power's waveform becomes Full-wave rectified sine, and its fundamental frequency

12544-416: The power failure experienced by Texas, did not have an increase in the number of deaths like Texas did, indicating a correlation in the increase in deaths and the loss of power. Alternating current The usual waveform of alternating current in most electric power circuits is a sine wave , whose positive half-period corresponds with positive direction of the current and vice versa (the full period

12672-459: The present time; they include solar heating , photovoltaics , wind power , solar thermal power stations , and modern forms of bioenergy . Third-generation technologies require continued R&D efforts in order to make large contributions on a global scale and include advanced biomass gasification , hot-dry-rock geothermal power, and ocean energy . In 2019, nearly 75% of new installed electricity generation capacity used renewable energy and

12800-582: The public sector has a role to play. First-generation technologies are widely used in locations with abundant resources. Their future use depends on the exploration of the remaining resource potential, particularly in developing countries, and on overcoming challenges related to the environment and social acceptance. Biomass , the burning of organic materials for heat and power, is a fully mature technology . Unlike most renewable sources, biomass (and hydropower) can supply stable base load power generation. Biomass produces CO 2 emissions on combustion, and

12928-546: The remaining generation". "Photovoltaic and concentrated solar power together can become the major source of electricity". In 2013, China led the world in renewable energy production, with a total capacity of 378 GW , mainly from hydroelectric and wind power . As of 2014, China leads the world in the production and use of wind power, solar photovoltaic power and smart grid technologies, generating almost as much water, wind and solar energy as all of France and Germany's power plants combined. China's renewable energy sector

13056-419: The renewable energy industries. According to a 2011 projection by the IEA, solar power generators may produce most of the world's electricity within 50 years, reducing harmful greenhouse gas emissions . Climate change , pollution, and energy insecurity are significant problems, and addressing them requires major changes to energy infrastructures. Renewable energy technologies are essential contributors to

13184-492: The same circuit. Many adjustable transformer designs were introduced to compensate for this problematic characteristic of the series circuit, including those employing methods of adjusting the core or bypassing the magnetic flux around part of a coil. The direct current systems did not have these drawbacks, giving it significant advantages over early AC systems. In the UK, Sebastian de Ferranti , who had been developing AC generators and transformers in London since 1882, redesigned

13312-414: The same phases with reverse polarity and so can be simply wired together. In practice, higher "pole orders" are commonly used. For example, a 12-pole machine would have 36 coils (10° spacing). The advantage is that lower rotational speeds can be used to generate the same frequency. For example, a 2-pole machine running at 3600 rpm and a 12-pole machine running at 600 rpm produce the same frequency;

13440-411: The skin depth of a copper conductor is approximately 8.57 mm at 60 Hz, so high current conductors are usually hollow to reduce their mass and cost. This tendency of alternating current to flow predominantly in the periphery of conductors reduces the effective cross-section of the conductor. This increases the effective AC resistance of the conductor, since resistance is inversely proportional to

13568-468: The sky to generate more electricity than conventional fixed-mounted systems. There are no fuel costs or emissions during operation of the power stations. Some of the second-generation renewables, such as wind power, have high potential and have already realised relatively low production costs. Wind power could become cheaper than nuclear power. Global wind power installations increased by 35,800 MW in 2010, bringing total installed capacity up to 194,400 MW,

13696-536: The standards for the complete system of generation, transmission and motors used in USA today. The original Niagara Falls Adams Power Plant with three two-phase generators was put into operation in August 1895, but was connected to the remote transmission system only in 1896. The Jaruga Hydroelectric Power Plant in Croatia was set in operation two days later, on 28 August 1895. Its generator (42 Hz, 240 kW)

13824-414: The state of Texas blamed the 2021 storm for the death of 151 people, later revised to 246. The true number is believed to be four to five times that number, as many deaths are often attributed to underlying medical conditions instead of being related to loss of power, which could cause the failure of life sustaining at-home medical devices. For comparison, other states hit by the same winter storm, but without

13952-419: The summer of 2019, providing an adequate though not generous margin. For 2020, the forecasted peak demand is 76,696 MW. A megawatt of electricity can power about 200 Texas homes during periods of peak demand. On Saturday, January 19, 2019, in an early morning period of low electricity demand, wind energy served more than 56% of total demand at 3:10 am, Central Standard Time. On Monday, January 21, 2019, ERCOT set

14080-433: The supply chain. Further improvements in the levelised cost of energy for solar, wind and other technologies lie ahead, posing a growing threat to the dominance of fossil fuel generation sources in the next few years. Hydro-electricity and geothermal electricity produced at favourable sites are now the cheapest way to generate electricity. Renewable energy costs continue to drop, and the levelised cost of electricity (LCOE)

14208-410: The supply side. For smaller customers (just how small varies by country and age of the installation) only a single phase and neutral, or two phases and neutral, are taken to the property. For larger installations all three phases and neutral are taken to the main distribution panel. From the three-phase main panel, both single and three-phase circuits may lead off. Three-wire single-phase systems, with

14336-451: The target or called for it to go further. Across the EU, 57 percent thought the proposed goal was "about right" and 16 percent thought it was "too modest." In comparison, 19 percent said it was "too ambitious". As of 2011, new evidence has emerged that there are considerable risks associated with traditional energy sources, and that major changes to the mix of energy technologies is needed: Several mining tragedies globally have underscored

14464-646: The task of redesigning the Gaulard and Gibbs transformer for commercial use in United States. On March 20, 1886, Stanley conducted a demonstrative experiment in Great Barrington : A Siemens generator's voltage of 500 volts was converted into 3000 volts, and then the voltage was stepped down to 500 volts by six Westinghouse transformers. With this setup, the Westinghouse company successfully powered thirty 100-volt incandescent bulbs in twenty shops along

14592-707: The theoretical basis of alternating current calculations include Charles Steinmetz , Oliver Heaviside , and many others. Calculations in unbalanced three-phase systems were simplified by the symmetrical components methods discussed by Charles LeGeyt Fortescue in 1918. Renewable energy commercialization Renewable energy commercialization involves the deployment of three generations of renewable energy technologies dating back more than 100 years. First-generation technologies, which are already mature and economically competitive, include biomass , hydroelectricity , geothermal power and heat. Second-generation technologies are market-ready and are being deployed at

14720-403: The upstream distribution panel to handle harmonics . Harmonics can cause neutral conductor current levels to exceed that of one or all phase conductors. For three-phase at utilization voltages a four-wire system is often used. When stepping down three-phase, a transformer with a Delta (3-wire) primary and a Star (4-wire, center-earthed) secondary is often used so there is no need for a neutral on

14848-578: The use of parallel connected, instead of series connected, utilization loads, the other concerning the ability to have high turns ratio transformers such that the supply network voltage could be much higher (initially 1400 V to 2000 V) than the voltage of utilization loads (100 V initially preferred). When employed in parallel connected electric distribution systems, closed-core transformers finally made it technically and economically feasible to provide electric power for lighting in homes, businesses and public spaces. The other essential milestone

14976-519: The way to integrate older plants into a universal AC supply system. In the autumn of 1884, Károly Zipernowsky , Ottó Bláthy and Miksa Déri (ZBD), three engineers associated with the Ganz Works of Budapest, determined that open-core devices were impractical, as they were incapable of reliably regulating voltage. Bláthy had suggested the use of closed cores, Zipernowsky had suggested the use of parallel shunt connections , and Déri had performed

15104-477: The wire are a product of the square of the current ( I ) and the resistance (R) of the wire, described by the formula: This means that when transmitting a fixed power on a given wire, if the current is halved (i.e. the voltage is doubled), the power loss due to the wire's resistance will be reduced to one quarter. The power transmitted is equal to the product of the current and the voltage (assuming no phase difference); that is, Consequently, power transmitted at

15232-551: The world potential capacity for geothermal power generation vary widely, ranging from 40 GW by 2020 to as much as 6,000 GW. Geothermal power capacity grew from around 1 GW in 1975 to almost 10 GW in 2008. The United States is the world leader in terms of installed capacity, representing 3.1 GW. Other countries with significant installed capacity include the Philippines (1.9 GW), Indonesia (1.2 GW), Mexico (1.0 GW), Italy (0.8 GW), Iceland (0.6 GW), Japan (0.5 GW), and New Zealand (0.5 GW). In some countries, geothermal power accounts for

15360-483: The world's transport fuel and recent estimates indicate a continued high growth. The main producing countries for transport biofuels are the US, Brazil, and the EU. Brazil has one of the largest renewable energy programs in the world, involving production of ethanol fuel from sugar cane , and ethanol now provides 18 percent of the country's automotive fuel. As a result of this and the exploitation of domestic deep water oil sources, Brazil, which for years had to import

15488-667: The worlds total electricity and 70% of all renewable electricity and is expected to increase about 3.1% each year for the next 25 years. Hydroelectric plants have the advantage of being long-lived and many existing plants have operated for more than 100 years. Hydropower is produced in 150 countries, with the Asia-Pacific region generating 32 percent of global hydropower in 2010. China is the largest hydroelectricity producer, with 721 terawatt-hours of production in 2010, representing around 17 percent of domestic electricity use. There are now three hydroelectricity plants larger than 10 GW:

15616-544: Was 3.1%. The wind industry is able to produce more power at lower cost by using taller wind turbines with longer blades, capturing the faster winds at higher elevations. This has opened up new opportunities and in Indiana, Michigan, and Ohio, the price of power from wind turbines built 300 feet to 400 feet above the ground can now compete with conventional fossil fuels like coal. Prices have fallen to about 4 cents per kilowatt-hour in some cases and utilities have been increasing

15744-560: Was independently invented by Galileo Ferraris and Nikola Tesla (with Tesla's design being licensed by Westinghouse in the US). This design was independently further developed into the modern practical three-phase form by Mikhail Dolivo-Dobrovolsky and Charles Eugene Lancelot Brown in Germany on one side, and Jonas Wenström in Sweden on the other, though Brown favoured the two-phase system. A long-distance alternating current transmission

15872-547: Was installed in Telluride Colorado. The first three-phase system was established in 1891 in Frankfurt , Germany. The Tivoli – Rome transmission was completed in 1892. The San Antonio Canyon Generator was the third commercial single-phase hydroelectric AC power plant in the United States to provide long-distance electricity. It was completed on December 31, 1892, by Almarian William Decker to provide power to

16000-507: Was made and installed by the Hungarian company Ganz , while the transmission line from the power plant to the City of Šibenik was 11.5 kilometers (7.1 mi) long, and the municipal distribution grid 3000 V/110 V included six transforming stations. Alternating current circuit theory developed rapidly in the latter part of the 19th and early 20th century. Notable contributors to

16128-596: Was not feasible in the early days of electric power transmission , as there was then no economically viable way to step the voltage of DC down for end user applications such as lighting incandescent bulbs. Three-phase electrical generation is very common. The simplest way is to use three separate coils in the generator stator , physically offset by an angle of 120° (one-third of a complete 360° phase) to each other. Three current waveforms are produced that are equal in magnitude and 120° out of phase to each other. If coils are added opposite to these (60° spacing), they generate

16256-506: Was the introduction of 'voltage source, voltage intensive' (VSVI) systems' by the invention of constant voltage generators in 1885. In early 1885, the three engineers also eliminated the problem of eddy current losses with the invention of the lamination of electromagnetic cores. Ottó Bláthy also invented the first AC electricity meter . The AC power system was developed and adopted rapidly after 1886 due to its ability to distribute electricity efficiently over long distances, overcoming

16384-754: Was used in 1883 for the Metropolitan Railway station lighting in London , while the single-phase 1884 system in Turin , Italy, was the first multiple-user AC distribution system in the world. The Ames Hydroelectric Generating Plant , constructed in 1890, was among the first hydroelectric alternating current power plants. A long distance transmission of single-phase electricity from a hydroelectric generating plant in Oregon at Willamette Falls sent power fourteen miles downriver to downtown Portland for street lighting in 1890. In 1891, another transmission system

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