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Pondage
Pondage usually refers to the comparably small water storage behind the weir of a run-of-the-river hydroelectric power plant. Such a power plant has considerably less storage than the reservoirs of large dams and conventional hydroelectric stations which can store water for long periods such as a dry season or year. With pondage, water is usually stored during periods of low electricity demand and hours when the power plant is inactive, enabling its use as a peaking power plant Peaking power plants, also known as peaker plants, and occasionally just "peakers", are power plants that generally run only when there is a high demand, known as peak demand, for electricity. Because they supply power only occasionally, the powe ... in dry seasons and a base load power plant during wet seasons. Ample pondage allows a power plant to meet hourly load fluctuations for a period of a week or more. As a daily hydropeaking cycle of a hydro power plant with pondage results in fast rising river ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weir
A weir or low head dam is a barrier across the width of a river that alters the flow characteristics of water and usually results in a change in the height of the river level. Weirs are also used to control the flow of water for outlets of lakes, ponds, and reservoirs. There are many weir designs, but commonly water flows freely over the top of the weir crest before cascading down to a lower level. Etymology There is no single definition as to what constitutes a weir and one English dictionary simply defines a weir as a small dam, likely originating from Middle English ''were'', Old English ''wer'', derivative of root of ''werian,'' meaning "to defend, dam". Function Commonly, weirs are used to prevent flooding, measure water discharge, and help render rivers more navigable by boat. In some locations, the terms dam and weir are synonymous, but normally there is a clear distinction made between the structures. Usually, a dam is designed specifically to impound water beh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Run-of-the-river Hydroelectric
Run-of-river hydroelectricity (ROR) or run-of-the-river hydroelectricity is a type of hydroelectric generation plant whereby little or no water storage is provided. Run-of-the-river power plants may have no water storage at all or a limited amount of storage, in which case the storage reservoir is referred to as pondage. A plant without pondage is subject to seasonal river flows, thus the plant will operate as an intermittent energy source. Conventional hydro uses reservoirs, which regulate water for flood control, dispatchable electrical power, and the provision of fresh water for agriculture. Concept Run-of-the-river, or ROR, hydroelectricity is considered ideal for streams or rivers that can sustain a minimum flow or those regulated by a lake or reservoir upstream. A small dam is usually built to create a headpond ensuring that there is enough water entering the penstock pipes that lead to the turbines, which are at a lower elevation. Projects with pondage, as opposed t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peaking Power Plant
Peaking power plants, also known as peaker plants, and occasionally just "peakers", are power plants that generally run only when there is a high demand, known as peak demand, for electricity. Because they supply power only occasionally, the power supplied commands a much higher price per kilowatt hour than base load power. Peak load power plants are dispatched in combination with base load power plants, which supply a dependable and consistent amount of electricity, to meet the minimum demand. Although historically peaking power plants were frequently used in conjunction with coal baseload plants, peaking plants are now used less commonly. Combined cycle gas turbine plants have two or more cycles, the first of which is very similar to a peaking plant, with the second running on the waste heat of the first. That type of plant is often capable of rapidly starting up, albeit at reduced efficiency, and then over some hours transitioning to a more efficient baseload generation mode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base Load Power Plant
The base load (also baseload) is the minimum level of demand on an electrical grid over a span of time, for example, one week. This demand can be met by unvarying power plants, dispatchable generation, or by a collection of smaller intermittent energy sources, depending on which approach has the best mix of cost, availability and reliability in any particular market. The remainder of demand, varying throughout a day, is met by dispatchable generation which can be turned up or down quickly, such as load following power plants, peaking power plants, or energy storage. Power plants that do not change their power output quickly, such as large coal or nuclear plants, are generally called baseload power plants. Donald G. Fink, H. Wayne Beatty (ed), ''Standard Handbook for Electrical Engineers'', Eleventh Edition, Mc-Graw Hill, 1978 , pp. 12-16 through 12-18 Historically, most or all of base load demand was met with baseload power plants, whereas new capacity based around renewables ofte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Load Balancing (electrical Power)
Load balancing, load matching, or daily peak demand reserve refers to the use of various techniques by electrical power stations to store excess electrical power during low demand periods for release as demand rises. The aim is for the power supply system to have a load factor of 1. Grid energy storage stores electricity within the transmission grid beyond the customer. Alternatively, the storage can be distributed and involve the customer, for example in storage heaters running demand-response tariffs such as the United Kingdom's Economy 7, or in a vehicle-to-grid system to use storage from electric vehicles during peak times and then replenish it during off peak times. These require incentives for consumers to participate, usually by offering cheaper rates for off peak electricity. Batteries and smart grid Telephone exchanges often have arrays of batteries in their basements to power equipment and in the past metro systems such as the London Underground had their own power ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peaking Power Plant
Peaking power plants, also known as peaker plants, and occasionally just "peakers", are power plants that generally run only when there is a high demand, known as peak demand, for electricity. Because they supply power only occasionally, the power supplied commands a much higher price per kilowatt hour than base load power. Peak load power plants are dispatched in combination with base load power plants, which supply a dependable and consistent amount of electricity, to meet the minimum demand. Although historically peaking power plants were frequently used in conjunction with coal baseload plants, peaking plants are now used less commonly. Combined cycle gas turbine plants have two or more cycles, the first of which is very similar to a peaking plant, with the second running on the waste heat of the first. That type of plant is often capable of rapidly starting up, albeit at reduced efficiency, and then over some hours transitioning to a more efficient baseload generation mode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroelectricity
Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other renewable sources combined and also more than nuclear power. Hydropower can provide large amounts of low-carbon electricity on demand, making it a key element for creating secure and clean electricity supply systems. A hydroelectric power station that has a dam and reservoir is a flexible source, since the amount of electricity produced can be increased or decreased in seconds or minutes in response to varying electricity demand. Once a hydroelectric complex is constructed, it produces no direct waste, and almost always emits considerably less greenhouse gas than fossil fuel-powered energy plants. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
