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Emergency Power Control
Power system operations is a term used in electricity generation to describe the process of decision-making on the timescale from one day (day-ahead operation) to minutes prior to the power delivery. The term power system control describes actions taken in response to unplanned ''disturbances'' (e.g., changes in demand or equipment failures) in order to provide reliable electric supply of acceptable quality. The corresponding engineering branch is called Power System Operations and Control. Electricity is hard to store, so at any moment the supply (generation) shall be balanced with demand (" grid balancing"). In an electrical grid the task of real-time balancing is performed by a regional-based control center, run by an electric utility in the traditional ( vertically integrated) electricity market. In the restructured North American power transmission grid, these centers belong to '' balancing authorities'' numbered 74 in 2016, the entities responsible for operations are also c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electricity Generation
Electricity generation is the process of generating electric power from sources of primary energy. For electric utility, utilities in the electric power industry, it is the stage prior to its Electricity delivery, delivery (Electric power transmission, transmission, Electric power distribution, distribution, etc.) to end users or its Grid energy storage, storage, using for example, the Pumped-storage hydroelectricity, pumped-storage method. Consumable electricity is not freely available in nature, so it must be "produced", transforming other forms of energy to electricity. Production is carried out in power stations, also called "power plants". Electricity is most often generated at a power plant by electromechanical electric generator, generators, primarily driven by heat engines fueled by combustion or nuclear fission, but also by other means such as the kinetic energy of flowing water and wind. Other energy sources include solar photovoltaics and geothermal power. There are ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Power Station
A nuclear power plant (NPP), also known as a nuclear power station (NPS), nuclear generating station (NGS) or atomic power station (APS) is a thermal power station in which the heat source is a nuclear reactor. As is typical of thermal power stations, heat is used to generate steam that drives a steam turbine connected to a generator that produces electricity. , the International Atomic Energy Agency reported that there were 410 nuclear power reactors in operation in 32 countries around the world, and 57 nuclear power reactors under construction. Most nuclear power plants use thermal reactors with enriched uranium in a once-through fuel cycle. Fuel is removed when the percentage of neutron absorbing atoms becomes so large that a chain reaction can no longer be sustained, typically three years. It is then cooled for several years in on-site spent fuel pools before being transferred to long-term storage. The spent fuel, though low in volume, is high-level radioactiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Economic Dispatch
The merit order is a way of ranking available sources of energy, especially electrical generation, based on ascending order of price (which may reflect the order of their short-run marginal costs of production) and sometimes pollution, together with amount of energy that will be generated. In a centralized management scheme, the ranking is such that those with the lowest marginal costs are the first sources to be brought online to meet demand, and the plants with the highest marginal costs are the last to be brought on line. Dispatching power generation in this way, known as economic dispatch, minimizes the cost of production of electricity. Sometimes generating units must be started out of merit order, due to transmission congestion, system reliability or other reasons. In environmental dispatch, additional considerations concerning reduction of pollution further complicate the power dispatch problem. The basic constraints of the economic dispatch problem remain in place but the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voltage Collapse
Voltage, also known as (electrical) potential difference, electric pressure, or electric tension, is the difference in electric potential between two points. In a static electric field, it corresponds to the work needed per unit of charge to move a positive test charge from the first point to the second point. In the International System of Units (SI), the derived unit for voltage is the ''volt'' (''V''). The voltage between points can be caused by the build-up of electric charge (e.g., a capacitor), and from an electromotive force (e.g., electromagnetic induction in a generator). On a macroscopic scale, a potential difference can be caused by electrochemical processes (e.g., cells and batteries), the pressure-induced piezoelectric effect, and the thermoelectric effect. Since it is the difference in electric potential, it is a physical scalar quantity. A voltmeter can be used to measure the voltage between two points in a system. Often a common reference potential such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reactive Power Reserves
Voltage control and reactive power management are two facets of an ancillary service that enables reliability of the transmission networks and facilitates the electricity market on these networks. Both aspects of this activity are intertwined (voltage change in an alternating current (AC) network is effected through production or absorption of reactive power), so within this article the term ''voltage control'' will be primarily used to designate this essentially single activity, as suggested by Kirby & Hirst (1997). Voltage control does not include reactive power injections to dampen the grid oscillations; these are a part of a separate ancillary service, so-called system stability service. The transmission of reactive power is limited by its nature, so the voltage control is provided through pieces of equipment distributed throughout the power grid, unlike the frequency control that is based on maintaining the overall active power balance in the system. Need for voltage con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supplemental Reserve
In electricity networks, the operating reserve is the generating capacity available to the system operator within a short interval of time to meet demand in case a generator goes down or there is another disruption to the supply. Most power systems are designed so that, under normal conditions, the operating reserve is always at least the capacity of the largest supplier plus a fraction of the peak load. Types of operating reserve The operating reserve is made up of the spinning reserve as well as the non-spinning or supplemental reserve: * The spinning reserve is the extra generating capacity that is available by increasing the power output of generators that are already connected to the power system. For most generators, this increase in power output is achieved by increasing the torque applied to the turbine's rotor. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combined Heat And Power
Cogeneration or combined heat and power (CHP) is the use of a heat engine or power station to electricity generation, generate electricity and useful heat at the same time. Cogeneration is a more efficient use of fuel or heat, because otherwise-waste heat, wasted heat from electricity generation is put to some productive use. Combined heat and power (CHP) plants recover otherwise wasted thermal energy for HVAC#heating, heating. This is also called combined heat and power district heating. Small CHP plants are an example of Distributed generation, decentralized energy. By-product heat at moderate temperatures ( can also be used in absorption refrigerators for cooling. The supply of high-temperature heat first drives a gas turbine, gas or steam turbine-powered generator. The resulting low-temperature waste heat is then used for water or space heating. At smaller scales (typically below 1 MW), a gas engine or diesel engine may be used. Cogeneration is also common with geotherm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Contingency (electrical Grid)
In an electrical grid, contingency is an unexpected failure of a single principal component (e.g., an electrical generator or a power transmission line) that causes the change of the system state large enough to endanger the grid security. Some protective relays are set up in a way that multiple individual components are disconnected due to a single fault, in this case, taking out all the units in a group counts as a single contingency. A scheduled outage (like maintenance) is not a contingency. The choice of term emphasizes the fact that a single fault can cause severe damage to the system so quickly that the operator will not have time to intervene, and therefore a reaction to every single fault has to be defensively pre-built into the system configuration. Some sources use the term interchangeably with "disturbance" and "fault". Contingency analysis The contingency analysis application periodically runs on the computers at the operations centers providing suggestions to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinning Reserve
In electricity networks, the operating reserve is the generating capacity available to the system operator within a short interval of time to meet demand in case a generator goes down or there is another disruption to the supply. Most power systems are designed so that, under normal conditions, the operating reserve is always at least the capacity of the largest supplier plus a fraction of the peak load. Types of operating reserve The operating reserve is made up of the spinning reserve as well as the non-spinning or supplemental reserve: * The spinning reserve is the extra generating capacity that is available by increasing the power output of generators that are already connected to the power system. For most generators, this increase in power output is achieved by increasing the torque applied to the turbine's rotor. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merit Order
The merit order is a way of ranking available sources of energy, especially electrical generation, based on ascending order of price (which may reflect the order of their short-run marginal costs of production) and sometimes pollution, together with amount of energy that will be generated. In a centralized management scheme, the ranking is such that those with the lowest marginal costs are the first sources to be brought online to meet demand, and the plants with the highest marginal costs are the last to be brought on line. Dispatching power generation in this way, known as economic dispatch, minimizes the cost of production of electricity. Sometimes generating units must be started out of merit order, due to transmission congestion, system reliability or other reasons. In environmental dispatch, additional considerations concerning reduction of pollution further complicate the power dispatch problem. The basic constraints of the economic dispatch problem remain in place but the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auction
An auction is usually a process of Trade, buying and selling Good (economics), goods or Service (economics), services by offering them up for Bidding, bids, taking bids, and then selling the item to the highest bidder or buying the item from the lowest bidder. Some exceptions to this definition exist and are described in the section about different #Types, types. The branch of economic theory dealing with auction types and participants' behavior in auctions is called auction theory. The open ascending price auction is arguably the most common form of auction and has been used throughout history. Participants bid openly against one another, with each subsequent bid being higher than the previous bid. An auctioneer may announce prices, while bidders submit bids vocally or electronically. Auctions are applied for trade in diverse #Contexts, contexts. These contexts include antiques, Art auction, paintings, rare collectibles, expensive wine auction, wines, commodity, commodities, l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Market Clearing
In economics, market clearing is the process by which, in an economic market, the supply of whatever is traded is equated to the demand so that there is no excess supply or demand, ensuring that there is neither a surplus nor a shortage. The new classical economics assumes that in any given market, assuming that all buyers and sellers have access to information and that there is no "friction" impeding price changes, prices ''constantly'' adjust up or down to ensure market clearing. Mechanism and examples A market-clearing price is the price of a good or service at which the quantity supplied equals the quantity demanded, also called the equilibrium price. The theory claims that markets tend to move toward this price. Supply is fixed for a one-time sale of goods, so the market-clearing price is simply the maximum price at which all items can be sold. In a market where goods are produced and sold on an ongoing basis, the theory predicts that the market will move toward a price wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
