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85-517: A super grid or supergrid is a wide-area transmission network , generally trans-continental or multinational, that is intended to make possible the trade of high volumes of electricity across great distances. It is sometimes also referred to as a "mega grid". Super grids typically are proposed to use high-voltage direct current (HVDC) to transmit electricity long distances. The latest generation of HVDC power lines can transmit energy with losses of only 1.6% per 1,000 km. Super grids could support

170-490: A power outage , known as a blackout . A power outage (also called a power cut , a power out , a power blackout , power failure or a blackout ) is a loss of the electric power to a particular area. Wide area synchronous grid A wide area synchronous grid (also called an " interconnection " in North America ) is a three-phase electric power grid that has regional scale or greater that operates at

255-497: A controlled flow of energy while also functionally isolating the independent AC frequencies of each side. The benefits of synchronous zones include pooling of generation, resulting in lower generation costs; pooling of load, resulting in significant equalizing effects; common provisioning of reserves, resulting in cheaper primary and secondary reserve power costs; opening of the market, resulting in possibility of long-term contracts and short term power exchanges; and mutual assistance in

340-568: A controlled flow of energy while also functionally isolating the independent AC frequencies of each side. Each of the interconnects in North America is synchronized at a nominal 60 Hz, while those of Europe run at 50 Hz. The benefits of synchronous zones include pooling of generation, resulting in lower generation costs; pooling of load, resulting in significant equalizing effects; common provisioning of reserves, resulting in cheaper primary and secondary reserve power costs; opening of

425-465: A different region to ensure continuing, reliable power and diversify their loads. Interconnection also allows regions to have access to cheap bulk energy by receiving power from different sources. For example, one region may be producing cheap hydro power during high water seasons, but in low water seasons, another area may be producing cheaper power through wind, allowing both regions to access cheaper energy sources from one another during different times of

510-472: A global energy transition by smoothing local fluctuations of wind energy and solar energy . In this context they are considered as a key technology to mitigate global warming . The idea of creating long-distance transmission lines in order to take advantage of renewable sources distantly located is not new. In the US in the 1950s, a proposal was made to ship hydroelectric power from dams being constructed in

595-411: A grid to be able to provide sufficient current to keep the voltage and frequency reasonably stable until circuit breakers can resolve the fault. Many traditional generator systems had wires which could be overloaded for very short periods without damage, but inverters are not as able to deliver multiple times their rated load. The short circuit ratio can be calculated for each point on the grid, and if it

680-437: A large scale within an electrical power grid . Electrical energy is stored during times when electricity is plentiful and inexpensive (especially from intermittent power sources such as renewable electricity from wind power , tidal power and solar power ) or when demand is low, and later returned to the grid when demand is high, and electricity prices tend to be higher. As of 2020 , the largest form of grid energy storage

765-428: A local power grid, it will cause safety issue like burning out. Grids are designed to supply electricity to their customers at largely constant voltages. This has to be achieved with varying demand, variable reactive loads, and even nonlinear loads, with electricity provided by generators and distribution and transmission equipment that are not perfectly reliable. Often grids use tap changers on transformers near to

850-521: A loss of generation capacity for customers, or excess demand. This will often cause the frequency to reduce, and the remaining generators will react and together attempt to stabilize above the minimum. If that is not possible then a number of scenarios can occur. A large failure in one part of the grid — unless quickly compensated for — can cause current to re-route itself to flow from the remaining generators to consumers over transmission lines of insufficient capacity, causing further failures. One downside to

935-593: A result of network complexity, transmission congestion , and the need for rapid diagnostic, coordination and control systems. Such studies observe that transmission capacity would need to be significantly higher than current transmission systems in order to promote unimpeded energy trading across distances unbounded by state, regional or national, or even continental borders. As a practical matter, it has become necessary to incorporate smart grid features such as wide area sensor networks (WAMS) into even modest-sized regional grids in order to avert major power outages such as

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1020-422: A row with Serbia , leading to the phase in the whole synchronous grid of Continental Europe lagging behind what it should have been. The frequency dropped to 49.996 Hz. Over time, this caused synchronous electric clocks to become six minutes slow until the disagreement was resolved. (2007) (2018) (2020) (2016) (2022) A partial table of some of the larger interconnections. Historically, on

1105-402: A super grid is a very long-distance equivalent of a wide area synchronous network capable of large-scale transmission of renewable electricity. In some conceptions, a transmission grid of HVDC transmission lines forms a layer that is distinctly separate in the way that a superhighway system is separate from the system of city streets and regional highways. In more conventional conceptions such as

1190-586: A synchronized utility frequency and is electrically tied together during normal system conditions. Also known as synchronous zones , the most powerful is the Northern Chinese State Grid with 1,700 gigawatts (GW) of generation capacity, while the widest region served is that of the IPS/UPS system serving most countries of the former Soviet Union. Synchronous grids with ample capacity facilitate electricity trading across wide areas. In

1275-562: A synchronous grid is stored energy that a grid has available which can provide extra power for up to a few seconds to maintain the grid frequency. Historically, this was provided only by the angular momentum of the generators, and gave the control circuits time to adjust their output to variations in loads, and sudden generator or distribution failures. Inverters connected to HVDC usually have no inertia, but wind power can provide inertia, and solar and battery systems can provide synthetic inertia . In short circuit situations, it's important for

1360-464: A synchronous grid, all the generators naturally lock together electrically and run at the same frequency , and stay very nearly in phase with each other. For rotating generators, a local governor regulates the driving torque and helps maintain a more or less constant speed as loading changes. Droop speed control ensures that multiple parallel generators share load changes in proportion to their rating. Generation and consumption must be balanced across

1445-745: A widely connected grid is thus the possibility of cascading failure and widespread power outage . A central authority is usually designated to facilitate communication and develop protocols to maintain a stable grid. For example, the North American Electric Reliability Corporation gained binding powers in the United States in 2006, and has advisory powers in the applicable parts of Canada and Mexico. The U.S. government has also designated National Interest Electric Transmission Corridors , where it believes transmission bottlenecks have developed. A brownout

1530-524: Is three-phase . Three phase, compared to single phase, can deliver much more power for a given amount of wire, since the neutral and ground wires are shared. Further, three-phase generators and motors are more efficient than their single-phase counterparts. However, for conventional conductors one of the main losses are resistive losses which are a square law on current, and depend on distance. High voltage AC transmission lines can lose 1-4% per hundred miles. However, high-voltage direct current can have half

1615-511: Is a local grid that is usually part of the regional wide-area synchronous grid but which can disconnect and operate autonomously. It might do this in times when the main grid is affected by outages. This is known as islanding , and it might run indefinitely on its own resources. Compared to larger grids, microgrids typically use a lower voltage distribution network and distributed generators. Microgrids may not only be more resilient, but may be cheaper to implement in isolated areas. A design goal

1700-549: Is a wide area mega grid, but also because it is highly coordinated from a macro level spanning nations and continents, all the way down to the micro-level scheduling low priority loads like water heaters and refrigeration. In the European SuperSmart Grid proposal and the US Unified Smart Grid concept, such super grids have intelligence features in the wide-area transmission layer which integrate

1785-885: Is a wide-area transmission network that is intended to make possible the trade of high volumes of electricity across great distances. It is sometimes also referred to as a mega grid . Super grids can support a global energy transition by smoothing local fluctuations of wind energy and solar energy . In this context they are considered as a key technology to mitigate global warming . Super grids typically use High-voltage direct current (HVDC) to transmit electricity long distances. The latest generation of HVDC power lines can transmit energy with losses of only 1.6% per 1000 km. Electric utilities between regions are many times interconnected for improved economy and reliability. Electrical interconnectors allow for economies of scale, allowing energy to be purchased from large, efficient sources. Utilities can draw power from generator reserves from

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1870-498: Is an intentional or unintentional drop in voltage in an electrical power supply system. Intentional brownouts are used for load reduction in an emergency. The reduction lasts for minutes or hours, as opposed to short-term voltage sag (or dip). The term brownout comes from the dimming experienced by incandescent lighting when the voltage sags. A voltage reduction may be an effect of disruption of an electrical grid, or may occasionally be imposed in an effort to reduce load and prevent

1955-410: Is argued that a high capacity super grid must be built in order to provide a distribution network so comprehensive and with such available capacity that energy trading is only limited by how much electricity entrepreneurs can bring to market. Wide area super grids plans typically call for bulk transmission using high voltage direct current lines. Europe's SuperSmart Grid proposal relies on HVDC, and in

2040-463: Is because the feeder line from the generator to the transmission lines is usually paid for by the owner of the generation. Some localities will help pay for the cost of these lines, at the cost of local regulation such as that of a public utilities commission . T. Boone Pickens' project has chosen to pay for the feeder lines privately. Some localities, such as Texas give such projects the power of eminent domain which allows companies to seize land in

2125-501: Is ca. 11% of the World's population, had no access to grid electricity in 2017, down from 1.2 billion in 2010. Electrical grids can be prone to malicious intrusion or attack; thus, there is a need for electric grid security . Also as electric grids modernize and introduce computer technology, cyber threats start to become a security risk. Particular concerns relate to the more complex computer systems needed to manage grids. A microgrid

2210-422: Is dammed hydroelectricity , with both conventional hydroelectric generation as well as pumped storage hydroelectricity . Developments in battery storage have enabled commercially viable projects to store energy during peak production and release during peak demand, and for use when production unexpectedly falls giving time for slower responding resources to be brought online. Two alternatives to grid storage are

2295-506: Is found to be too low, for steps to be taken to increase it to be above 1, which is considered stable. For timekeeping purposes, over the course of a day the operating frequency will be varied so as to balance out deviations and to prevent line-operated clocks from gaining or losing significant time by ensuring there are 4.32 million on 50 Hz, and 5.184 million cycles on 60 Hz systems each day. This can, rarely, lead to problems. In 2018 Kosovo used more power than it generated due to

2380-461: Is output ( droop speed control ). When the grid is lightly loaded the grid frequency runs above the nominal frequency, and this is taken as an indication by Automatic Generation Control systems across the network that generators should reduce their output. In addition, there's often central control, which can change the parameters of the AGC systems over timescales of a minute or longer to further adjust

2465-417: Is simply rerouted while repairs are done. Because the power is often generated far from where it is consumed, the transmission system can cover great distances. For a given amount of power, transmission efficiency is greater at higher voltages and lower currents. Therefore, voltages are stepped up at the generating station, and stepped down at local substations for distribution to customers. Most transmission

2550-411: Is stored in the immediate short term by the rotational kinetic energy of the generators. Although the speed is kept largely constant, small deviations from the nominal system frequency are very important in regulating individual generators and are used as a way of assessing the equilibrium of the grid as a whole. When the grid is lightly loaded the grid frequency runs above the nominal frequency, and this

2635-408: Is taken as an indication by Automatic Generation Control systems across the network that generators should reduce their output. Conversely, when the grid is heavily loaded, the frequency naturally slows, and governors adjust their generators so that more power is output ( droop speed control ). When generators have identical droop speed control settings it ensures that multiple parallel generators with

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2720-569: Is that a local area produces all of the energy it uses. Example implementations include: A wide area synchronous grid , also known as an "interconnection" in North America, directly connects many generators delivering AC power with the same relative frequency to many consumers. For example, there are four major interconnections in North America (the Western Interconnection , the Eastern Interconnection ,

2805-570: Is the final stage in the delivery of power; it carries electricity from the transmission system to individual consumers. Substations connect to the transmission system and lower the transmission voltage to medium voltage ranging between 2  kV and 35 kV . But the voltage levels varies very much between different countries, in Sweden medium voltage are normally 10  kV between 20 kV . Primary distribution lines carry this medium voltage power to distribution transformers located near

2890-584: Is the maximum power output on a grid that is immediately available over a given time period, and is a far more useful figure. Most grid codes specify that the load is shared between the generators in merit order according to their marginal cost (i.e. cheapest first) and sometimes their environmental impact. Thus cheap electricity providers tend to be run flat out almost all the time, and the more expensive producers are only run when necessary. Failures are usually associated with generators or power transmission lines tripping circuit breakers due to faults leading to

2975-406: Is the process of generating electric power from sources of primary energy typically at power stations . Usually this is done with electromechanical generators driven by heat engines or the kinetic energy of water or wind. Other energy sources include solar photovoltaics , nuclear power , and geothermal power . The sum of the power outputs of generators on the grid is the production of

3060-474: Is the scale of energy and distances that are imagined possible in a super grid. Europe began unifying its grids in the 1950s and its largest unified grid is the synchronous grid of Continental Europe serving 24 countries. Serious work is being conducted on unification of this synchronous European grid (previously known as the UCTE grid), with the neighboring synchronous transmission grid of some CIS countries,

3145-559: The European Energy Exchange (EEX). Each of the interconnects in North America are run at a nominal 60 Hz, while those of Europe run at 50 Hz. Neighbouring interconnections with the same frequency and standards can be synchronized and directly connected to form a larger interconnection, or they may share power without synchronization via high-voltage direct current power transmission lines ( DC ties ), or with variable-frequency transformers (VFTs), which permit

3230-612: The IPS/UPS grid. If completed, the resulting massive grid would span 13 time zones stretching from the Atlantic to the Pacific. While such grids cover great distances, the capacity to transmit large volumes of electricity remains limited due to congestion and control issues. The SuperSmart Grid (Europe) and the Unified Smart Grid (US) specify major technological upgrades that proponents claim are necessary to assure

3315-636: The North American power transmission grid the Eastern and Western Interconnections were directly connected, and was at the time largest synchronous grid in the world, but this was found to be unstable, and they are now only DC interconnected. Interconnectors such as High-voltage direct current lines, solid-state transformers or variable-frequency transformers can be used to connect two alternating current interconnection networks which are not necessarily synchronized with each other. This provides

3400-483: The Northeast Blackout of 2003 . Dynamic interactions between power generation groups are increasingly complex, and transient disturbances that cascade across neighboring utilities can be sudden, large and violent, accompanied by abrupt changes in the network topology as operators attempt to manually stabilize the network. In the second sense of an advanced grid, the super grid is superior not only because it

3485-726: The Pacific Intertie project with a set of technical objections that were overruled. When the project was completed, consumers in Los Angeles saved approximately U.S. $ 600,000 per day by use of electric power from projects on the Columbia River rather than local power companies burning more expensive fossil fuel. Grid (electricity) Grids are nearly always synchronous, meaning all distribution areas operate with three phase alternating current (AC) frequencies synchronized (so that voltage swings occur at almost

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3570-562: The Pacific Northwest to consumers in Southern California , but it was opposed and scrapped. In 1961, U.S. president John F. Kennedy authorized a large public works project using new high-voltage, direct current technology from Sweden . The project was undertaken as a close collaboration between General Electric of the U.S. and ASEA of Sweden , and the system was commissioned in 1970. With several upgrades of

3655-621: The Quebec Interconnection and the Texas Interconnection ). In Europe one large grid connects most of Western Europe . A wide area synchronous grid (also called an "interconnection" in North America) is an electrical grid at a regional scale or greater that operates at a synchronized frequency and is electrically tied together during normal system conditions. These are also known as synchronous zones,

3740-409: The electricity transmission corridors used by the new transmission lines of a super grid. There can be significant opposition to the siting of power lines out of concerns about visual impact, anxiety over perceived health issues, and environmental concerns. The US has a process of designating National Interest Electric Transmission Corridors , and it is likely that this process would be used to specify

3825-642: The British electricity transmission system that are connected at voltages in excess of 200 kV (200,000 volts). British power system planners and operational staff therefore invariably speak of the Supergrid in this context; in practice the definition used captures all of the equipment owned by the National Grid company in England and Wales, and no other equipment. What has changed during the past 40 years

3910-520: The ENTSO-E in 2008, over 350,000 megawatt hours were sold per day on the European Energy Exchange (EEX). Neighbouring interconnections with the same frequency and standards can be synchronized and directly connected to form a larger interconnection, or they may share power without synchronization via high-voltage direct current power transmission lines (DC ties), solid-state transformers or variable-frequency transformers (VFTs), which permit

3995-539: The European-wide adoption of renewable energy and interlinking power grids using HVDC cables, indicates that Europe's entire power usage could come from renewables, with 70% total energy from wind at the same level of cost or lower as at present. To some critics, such a wide area transmission layer is not novel; they point out that the technology has little difference from that used for regional and national power transmission networks. Proponents respond that beyond

4080-473: The US, key decision makers such as Steven Chu favor a national long distance DC grid system. There are industry advocates of high voltage alternating current (HVAC). Although flexible alternating current transmission systems ( FACTS ) have drawbacks for long distances, American Electric Power has championed a 765 kV super grid they call I-765 that would provide 400 GW of extra transmission capacity required for producing 20% of US energy from wind farms based in

4165-414: The benefit of interconnection without the need to synchronize an even wider area. For example, compare the wide area synchronous grid map of Europe (in the introduction) with the map of HVDC lines (here to the right). Solid state transformers have larger losses than conventional transformers, but DC lines lack reactive impedance and overall HVDC lines have lower losses sending power over long distances within

4250-467: The consumers to adjust the voltage and keep it within specification. In a synchronous grid all the generators must run at the same frequency, and must stay very nearly in phase with each other and the grid. Generation and consumption must be balanced across the entire grid, because energy is consumed as it is produced. For rotating generators, a local governor regulates the driving torque, maintaining almost constant rotation speed as loading changes. Energy

4335-703: The converter stations in the intervening decades, the system now has a capacity of 3,100 MW and is known as the Pacific DC Intertie . The concept of a "super grid" dates back to the 1960s and was used to describe the emerging unification of the Great Britain grid. In the code that governs the British Grid, the Grid Code, the Supergrid is currently defined – and has been since this code was first written, in 1990 – as referring to those parts of

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4420-429: The course of a whole 24 hour period. An entire synchronous grid runs at the same frequency, neighbouring grids would not be synchronised even if they run at the same nominal frequency. High-voltage direct current lines or variable-frequency transformers can be used to connect two alternating current interconnection networks which are not synchronized with each other. This provides the benefit of interconnection without

4505-456: The customer's premises. Distribution transformers again lower the voltage to the utilization voltage . Customers demanding a much larger amount of power may be connected directly to the primary distribution level or the subtransmission level. Distribution networks are divided into two types, radial or network. In cities and towns of North America, the grid tends to follow the classic radially fed design. A substation receives its power from

4590-431: The entire grid because energy is consumed as it is produced. Energy is stored in the immediate short term by the rotational kinetic energy of the generators. Small deviations from the nominal system frequency are very important in regulating individual generators and assessing the equilibrium of the grid as a whole. When the grid is heavily loaded, the frequency slows, and governors adjust their generators so that more power

4675-508: The event of disturbances. One disadvantage of a wide-area synchronous grid is that problems in one part can have repercussions across the whole grid. For example, in 2018 Kosovo used more power than it generated due to a dispute with Serbia , leading to the phase across the whole synchronous grid of Continental Europe lagging behind what it should have been. The frequency dropped to 49.996 Hz. This caused certain kinds of clocks to become six minutes slow. A super grid or supergrid

4760-494: The grid, typically measured in gigawatts (GW). Electric power transmission is the bulk movement of electrical energy from a generating site, via a web of interconnected lines, to an electrical substation , from which is connected to the distribution system. This networked system of connections is distinct from the local wiring between high-voltage substations and customers. Transmission networks are complex with redundant pathways. Redundancy allows line failures to occur and power

4845-439: The idea of a national transmission grid in order to promote United States energy independence . Al Gore advocates the Unified Smart Grid which has comprehensive super grid capabilities. Gore and other advocates such as James E. Hansen believe super grids are essential for the eventual complete replacement of the greenhouse gas producing fossil fuel use that feeds global warming . Large amounts of land would be required for

4930-450: The installation of renewable energy , currently in planning stage. One study for a European super grid estimates that as much as 750 GW of extra transmission capacity would be required – capacity that would be accommodated in increments of 5 GW with HVDC lines. A 2008 proposal by Transcanada priced a 1,600-km, 3 GW HVDC line at US$ 3 billion; it would require a corridor 60 meters wide. In India, an August 2007 6 GW, 1,825-km proposal

5015-409: The largest of which is the synchronous grid of Continental Europe (ENTSO-E) with 667  gigawatts (GW) of generation, and the widest region served being that of the IPS/UPS system serving countries of the former Soviet Union. Synchronous grids with ample capacity facilitate electricity market trading across wide areas. In the ENTSO-E in 2008, over 350,000 megawatt hours were sold per day on

5100-545: The local smart grid into a virtual power plant , or a city's fleet of one million electric vehicles could be used to trim peaks in transmission supply by integrating them to the smart grid using vehicle to grid technology. One advantage of such a geographically dispersed and dynamically balanced system is that the need for baseload generation is significantly reduced since intermittency of some sources such as ocean , solar , and wind can be smoothed. A series of detailed modeling studies by Dr. Gregor Czisch, which looked at

5185-544: The local smart grids into a single wide-area super grid. This is similar to how the Internet bound together multiple small networks into a single ubiquitous network. Wide area transmission can be viewed as a horizontal extension of the smart grid. In a paradigm shift, the distinction between transmission and distribution blurs with the integration as energy flow becomes bidirectional. For example, distribution grids in rural areas might generate more energy than they use, turning

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5270-542: The losses of AC. Over very long distances, these efficiencies can offset the additional cost of the required AC/DC converter stations at each end. Substations may perform many different functions but usually transform voltage from low to high (step up) and from high to low (step down). Between the generator and the final consumer, the voltage may be transformed several times. The three main types of substations, by function, are: Aside from transformers, other major components or functions of substations include: Distribution

5355-409: The market, resulting in possibility of long term contracts and short term power exchanges; and mutual assistance in the event of disturbances. One disadvantage of a wide-area synchronous grid is that problems in one part can have repercussions across the whole grid. Wide area synchronous networks improve reliability and permit the pooling of resources. Also, they can level out the load, which reduces

5440-400: The midwest. (See figure above). Advocates of HVAC systems point out that HVDC systems are oriented for point to point bulk transmission and multiple connections to them would require expensive complex communication and control equipment as opposed to the simple step up transformers needed if AC lines were used. Currently, there is only one multipoint long distance HVDC transmission system. In

5525-498: The more distant future, the voltage loss of current methods could be avoided using experimental superconducting " SuperGrid " technology where the transmission cable is cooled by a liquid hydrogen pipeline which is also used to move energy nationwide. The energy losses for creating, containing, and re-cooling liquid hydrogen need to be accounted for. Coordination and control of the network would use smart grid technologies such as phasor measurement units to rapidly detect imbalances in

5610-694: The need to synchronize an even wider area. For example, compare the wide area synchronous grid map of Europe with the map of HVDC lines. The sum of the maximum power outputs ( nameplate capacity ) of the generators attached to an electrical grid might be considered to be the capacity of the grid. However, in practice, they are never run flat out simultaneously. Typically, some generators are kept running at lower output powers ( spinning reserve ) to deal with failures as well as variation in demand. In addition generators can be off-line for maintenance or other reasons, such as availability of energy inputs (fuel, water, wind, sun etc.) or pollution constraints. Firm capacity

5695-409: The network caused by fluctuating renewable energy sources and potentially respond instantaneously with programmed automatic protection schemes to reroute, reduce load, or reduce generation in response to network disturbances. China supports the idea of a global, intercontinental super grid. For a super grid in the US, a study estimated an 80% reduction of greenhouse gas emissions in combination with

5780-516: The network to permit greater control during off-nominal events. As was discovered in the California electricity crisis , there can be strong incentives among some market traders to create deliberate congestion and poor management of generation capacity on an interconnection network to inflate prices. Increasing transmission capacity and expanding the market by uniting with neighbouring synchronous networks make such manipulations more difficult. In

5865-459: The path of the planned construction. Energy producers are interested in whether the super grid employs HVDC technology, or uses AC, because the cost of connection to an HVDC line is generally greater than that if the AC is used. The Pickens plan favors 765 kV AC transmission, which is considered to be less efficient for long-distance transmission. In the 1960s, private California power companies opposed

5950-561: The pathways for a super grid in that country. In the EU, permits for new overhead lines can easily reach 10 years. In some cases, this has made underground cable more expedient. Since land required can be one fifth than that for overhead and the permit process can be significantly faster, underground cable can be more attractive despite its weaknesses of being more expensive, lower capacity, shorter-lived, and suffering significantly longer downtimes. Just as superhighways change valuations of land due to

6035-399: The practical operation and promised benefits of such transcontinental mega grids. In current usage, "super grid" has two senses – one of being a superstructure layer overlaid or super-imposed upon existing regional transmission grid or grids, and the second of having some set of superior abilities exceeding those of even the most advanced grids. In the "overlay", or "superstructure" meaning,

6120-447: The proposed unification of the synchronous European grid UCTE and the IPS/UPS system of the CIS , such a mega grid is no different from typical wide area synchronous transmission systems where electricity takes an ad hoc transit route directly through local utility transmission lines or HVDC lines as required. Studies for such continental sized systems report there are scaling problems as

6205-433: The proximity to the ability to transport valuable commodities, businesses are strongly motivated to influence the siting of a super grid to their benefit. The cost of alternative power is the delivered price of electricity, and if the production of electricity from North Dakota wind or Arizona solar is to be competitive, the distance of the connection from the wind farm to the interstate transmission grid must not be great. This

6290-491: The qualitative smart grid features that allow instantaneous coordination and balancing of intermittent power sources across international boundaries, the quantitative comprehensiveness has a quality all its own. The claim is made that super grids open up markets. In the same way that freeways revolutionized interstate transport and the Internet revolutionized online commerce when comprehensive high-capacity networks were built, it

6375-403: The regional network flows and the operating frequency of the grid. Where neighbouring grids, operating at different frequencies, need to be interconnected, a frequency converter is required. HVDC Interconnectors , solid-state transformers or variable-frequency transformers links can connect two grids that operate at different frequencies or that are not maintaining synchronism. Inertia in

6460-490: The required generating capacity, allow more environmentally-friendly power to be employed; allow more diverse power generation schemes and permit economies of scale. Wide area synchronous networks cannot be formed if the two networks to be linked are running at different frequencies or have significantly different standards. For example, in Japan, for historical reasons, the northern part of the country operates on 50 Hz, but

6545-466: The same settings share load in proportion to their rating. In addition, there's often central control, which can change the parameters of the AGC systems over timescales of a minute or longer to further adjust the regional network flows and the operating frequency of the grid. For timekeeping purposes, the nominal frequency will be allowed to vary in the short term, but is adjusted to prevent line-operated clocks from gaining or losing significant time over

6630-513: The same time). This allows transmission of AC power throughout the area, connecting the electricity generators with consumers. Grids can enable more efficient electricity markets . Although electrical grids are widespread, as of 2016 , 1.4 billion people worldwide were not connected to an electricity grid. As electrification increases, the number of people with access to grid electricity is growing. About 840 million people (mostly in Africa), which

6715-468: The southern part uses 60 Hz. That makes it impossible to form a single synchronous network, which was problematic when the Fukushima Daiichi plant melted down. Also, even when the networks have compatible standards, failure modes can be problematic. Phase and current limitations can be reached, which can cause widespread outages. The issues are sometimes solved by adding HVDC links within

6800-404: The substation, but for reliability reasons, usually contains at least one unused backup connection to a nearby substation. This connection can be enabled in case of an emergency, so that a portion of a substation's service territory can be alternatively fed by another substation. Grid energy storage (also called large-scale energy storage ) is a collection of methods used for energy storage on

6885-433: The transmission network, the power is stepped down with a transformer and sent to a bus from which feeders fan out in all directions across the countryside. These feeders carry three-phase power, and tend to follow the major streets near the substation. As the distance from the substation grows, the fanout continues as smaller laterals spread out to cover areas missed by the feeders. This tree-like structure grows outward from

6970-414: The use of peaking power plants to fill in supply gaps and demand response to shift load to other times. The demand, or load on an electrical grid is the total electrical power being removed by the users of the grid. The graph of the demand over time is called the demand curve . Baseload is the minimum load on the grid over any given period, peak demand is the maximum load. Historically, baseload

7055-437: The year. Neighboring utilities also help others to maintain the overall system frequency and also help manage tie transfers between utility regions. Electricity Interconnection Level (EIL) of a grid is the ratio of the total interconnector power to the grid divided by the installed production capacity of the grid. Within the EU, it has set a target of national grids reaching 10% by 2020, and 15% by 2030. Electricity generation

7140-404: Was commonly met by equipment that was relatively cheap to run, that ran continuously for weeks or months at a time, but globally this is becoming less common. The extra peak demand requirements are sometimes produced by expensive peaking plants that are generators optimised to come on-line quickly but these too are becoming less common. However, if the demand of electricity exceed the capacity of

7225-433: Was priced at $ 790 million and would require a 69 meter wide right of way. With 750 GW of new HVDC transmission capacity required for a European super grid, the land and money needed for new transmission lines would be considerable. In Europe, the energy security implication of a super grid has been discussed as a way in part to prevent Russian energy hegemony . In the US, advocates such as T. Boone Pickens have promoted

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