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Cogeneration (also combined heat and power, CHP) is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat. Image File history File links Portal. ... CHP can mean: combined heat and power California Highway Patrol Cumhuriyet Halk Partisi (Republican Peoples Party of Turkey) Christian Heritage Party CHP - Netzwerk innovatives Planen - Generalplanungen im Bauwesen - http://www. ... A heat engine is a physical or theoretical device that converts thermal energy to mechanical output. ... For other uses, see Power station (disambiguation). ... Electricity (from New Latin Ä“lectricus, amberlike) is a general term for a variety of phenomena resulting from the presence and flow of electric charge. ... For other uses, see Heat (disambiguation) In physics, heat, symbolized by Q, is energy transferred from one body or system to another due to a difference in temperature. ...

Conventional power plants emit the heat created as a byproduct of electricity generation into the environment through cooling towers, flue gas, or by other means. CHP or a bottoming cycle captures the byproduct heat for domestic or industrial heating purposes, either very close to the plant, or —especially in Scandinavia and eastern Europe—for distribution through pipes to heat local housing. World-wide electricity production for 1980 to 2005. ... Image 1: Natural draft wet cooling hyperboloid towers at Didcot Power Station, UK Image 2: A mechanical induced draft cooling tower In rare cases, a plants cooling towers have even been painted to improve public perception as with the Cruas Nuclear Power Plant. ... Flue gas is gas that exits to the atmosphere via a flue, which is a pipe or channel for conveying exhaust gases from a fireplace, oven, furnace, boiler or steam generator. ... HVAC may also stand for High-voltage alternating current HVAC is an initialism that stands for heating, ventilation and air-conditioning. This is sometimes referred to as climate control. ... For other uses, see Scandinavia (disambiguation). ... For other uses, see Europe (disambiguation). ... District heating pipe in Tübingen, Germany District heating (less commonly called teleheating) is a system for distributing heat generated in a centralized location for residential and commercial heating requirements. ...

In the United States, Con Edison produces 30 billion pounds of steam each year through its seven cogeneration plants (which boil water to 1,000°F/538°C^{[citation needed]}) before pumping it to 100,000 buildings in Manhattan—the biggest commercial steam system in the world.^[1][2] Consolidated Edison Company of New York (NYSE: ED) (Con Edison, or Con Ed) is a utility company in New York state, USA. Con Edison is a regulated utility that provides electric service in New York City and most of Westchester County, New York. ... Fahrenheit is a temperature scale named after the German physicist Gabriel Fahrenheit (1686–1736), who proposed it in 1724. ... The degree Celsius (°C) is a unit of temperature named after the Swedish astronomer Anders Celsius (1701–1744), who first proposed a similar system in 1742. ... This article is about the borough of New York City. ...

Byproduct heat at moderate temperatures (212-356°F/100-180°C) can also be used in absorption chillers for cooling. A plant producing electricity, heat and cold is sometimes called trigeneration or more generally: polygeneration plant. The absorption refrigerator is a refrigerator that utilizes a heat source to provide the energy needed to drive the cooling system rather than being dependent on electricity to run a compressor. ... Trigeneration implies the simultaneous production of mechanical power (often converted to electricity), heat and cooling from a single heat source such as solar energy or fuel. ...

Cogeneration is a thermodynamically efficient use of fuel. In separate production of electricity some energy must be rejected as waste heat, but in cogeneration this thermal energy is put to good use. The thermal efficiency () is a dimensionless performance measure of a thermal device such as an internal combustion engine, a boiler, or a furnace, for example. ... For other uses, see Fuel (disambiguation). ... Waste heat is the by-product heat of machines and technical processes for which no useful application is found. ... In thermal physics, thermal energy is the energy portion of a system that increases with its temperature. ...

Overview

Masnedø CHP power station in Denmark. This station burns straw as fuel. The plant heats adjacent greenhouses.

Thermal power plants (including those that use fissile elements or burn coal, petroleum, or natural gas), and heat engines in general, do not convert all of their available energy into electricity. In most heat engines, a bit more than half is wasted as excess heat (see: Second law of thermodynamics). By capturing the excess heat, CHP uses heat that would be wasted in a conventional power plant, potentially reaching an efficiency of up to 89%, compared with 55%^[3] for the best conventional plants. This means that less fuel needs to be consumed to produce the same amount of useful energy. Also, less pollution is produced for a given economic benefit. Image File history File links Download high-resolution version (2003x677, 181 KB) Masnedø straw-fired combined heat and power station on the island of Masnedø, Denmark. ... Image File history File links Download high-resolution version (2003x677, 181 KB) Masnedø straw-fired combined heat and power station on the island of Masnedø, Denmark. ... Masnedø is a Danish island between Zealand and Falster. ... This article is about the chemical element. ... Coal Example chemical structure of coal Coal is a fossil fuel formed in ecosystems where plant remains were saved by water and mud from oxidization and biodegradation. ... Petro redirects here. ... For other uses, see Natural gas (disambiguation). ... A heat engine is a physical or theoretical device that converts thermal energy to mechanical output. ... The second law of thermodynamics is an expression of the universal law of increasing entropy. ... A power station (also power plant) is a facility for the generation of electric power. ... The thermal efficiency () is a dimensionless performance measure of a thermal device such as an internal combustion engine, a boiler, or a furnace, for example. ...

Some tri-cycle plants have utilized a combined cycle in which several thermodynamic cycles produced electricity, and then a heating system was used as a condenser of the power plant's bottoming cycle. For example, the RU-25 MHD generator in Moscow heated a boiler for a conventional steam powerplant, whose condensate was then used for space heat. A more modern system might use a gas turbine powered by natural gas, whose exhaust powers a steam plant, whose condensate provides heat. Tri-cycle plants can have thermal efficiencies above 80%. A combined cycle is characteristic of a power producing engine or plant that employs more than one thermodynamic cycle. ... Combined cycle describes when a power producing engine or plant employs more than one thermodynamic cycle. ... // The MHD (magnetohydrodynamic) generator or dynamo transforms thermal energy or kinetic energy directly into electricity. ... For other uses, see Moscow (disambiguation). ... This machine has a single-stage centrifugal compressor and turbine, a recuperator, and foil bearings. ... For other uses, see Natural gas (disambiguation). ...

An exact match between the heat and electricity needs rarely exists. A CHP plant can either meet the need for heat (heat driven operation) or be run as a power plant with some use of its waste heat. A power station (also power plant) is a facility for the generation of electric power. ...

CHP is most efficient when the heat can be used on site or very close to it. Overall efficiency is reduced when the heat must be transported over longer distances. This requires heavily insulated pipes, which are expensive and inefficient; whereas electricity can be transmitted along a comparatively simple wire, and over much longer distances for the same energy loss.

A car engine becomes a CHP plant in winter, when the reject heat is useful for warming the interior of the vehicle. This example illustrates the point that deployment of CHP depends on heat uses in the vicinity of the heat engine.

Cogeneration plants are commonly found in district heating systems of big towns, hospitals, prisons, oil refineries, paper mills, wastewater treatment plants, thermal enhanced oil recovery wells and industrial plants with large heating needs. District heating pipe in Tübingen, Germany District heating (less commonly called teleheating) is a system for distributing heat generated in a centralized location for residential and commercial heating requirements. ... Enhanced Oil Recovery (EOR) is a generic term for techniques for increasing the amount of oil that can be extracted from an oil field. ...

Thermally enhanced oil recovery (TEOR) plants often produce a substantial amount of excess electricity. After generating electricity, these plants pump leftover steam into heavy oil wells so that the oil will flow more easily, increasing production. TEOR cogeneration plants in Kern County, California produce so much electricity that it cannot all be used locally and is transmitted to Los Angeles^{[citation needed]}. Enhanced Oil Recovery (EOR) is a generic term for techniques for increasing the amount of oil that can be extracted from an oil field. ... Kern County is a county located in the southern Central Valley of the U.S. state of California. ... Flag Seal Nickname: City of Angels Location Location within Los Angeles County in the state of California Coordinates , Government State County California Los Angeles County Mayor Antonio Villaraigosa (D) Geographical characteristics Area     City 1,290. ...

Types of plants

Topping cycle plants produce electricity first, then the exhausted steam is used for heating. Flames naturally produce heat suitable for a boiler. The hot water from condensed steam is well-suited for space and water heating. Combined cycle is a term used when a power producing engine or plant employs more than one thermodynamic cycle. ...

Bottoming cycle plants produce high heats for an industrial process, then a waste heat recovery boiler feeds an electrical plant. Bottoming cycle plants are only used when the industrial process requires very high temperatures, such as furnaces for glass and metal manufacturing, so they are rarer. Combined cycle describes when a power producing engine or plant employs more than one thermodynamic cycle. ...

Large cogeneration systems provide heating water and power for an industrial site or an entire town. Common CHP plant types are:

• Gas turbine CHP plants using the waste heat in the flue gas of gas turbines
• Combined cycle power plants adapted for CHP
• Steam turbine CHP plants that use the heating system as the steam condenser for the steam turbine.
• Molten-carbonate fuel cells have a hot exhaust, very suitable for heating.

Smaller cogeneration units may use a reciprocating engine or Stirling engine. The heat is removed from the exhaust and the radiator. These systems are popular in small sizes because small gas and diesel engines are less expensive than small gas- or oil-fired steam-electric plants. This machine has a single-stage centrifugal compressor and turbine, a recuperator, and foil bearings. ... A combined cycle is characteristic of a power producing engine or plant that employs more than one thermodynamic cycle. ... A rotor of a modern steam turbine, used in a power plant A steam turbine is a mechanical device that extracts thermal energy from pressurized steam, and converts it into useful mechanical work. ... For other uses, see Steam (disambiguation). ... Scheme of a molten-carbonate fuel cell Molten-carbonate fuel cells (MCFCs) are high-temperature fuel cells, in the range of 600ºC. They operate at the highest efficiencies of any type fuel cell, including solid oxide fuel cells, proton exchange membrane fuel cells and phosphoric acid fuel cell and... Internal combustion piston engine Components of a typical, four stroke cycle, internal combustion piston engine. ... Cut away diagram of a Rhombic Drive Beta Stirling Engine Design Pink - Hot cylinder wall Dark Grey - Cold cylinder wall (with coolant inlet and outlet pipes in Yellow) Dark Green - Thermal insulation separating the two cylinder ends Light Green - Displacer piston Dark Blue - Power piston Light Blue - Flywheels Not Shown...

Some cogeneration plants are fired by biomass ^[4], or industrial and municipal waste (see incineration). For the use of the term in ecology, see Biomass (ecology). ... Municipal waste are a loud band from Richmond, VA. They play crossover thrash in the vein of DRI and Sepultura. ... For other forms of waste plant that produce energy see waste-to-energy. ...

MicroCHP

"Micro cogeneration" is a so called distributed energy resource (DER). the installation is usually in a house or small business[1]. Instead of burning fuel to merely heat space or water, some of the energy is converted to electricity in addition to heat. This electricity can be used within the home or business, or (if permitted by the grid management) sold back into the electric power grid. Micro Combined Heat and Power or MicroCHP is an extension of the now well established idea of Cogeneration to the single/multi family home or small office building. ... Distributed generation generates electricity from many small energy sources. ...

Current (2007) MicroCHP installations use five different technologies: microturbines, internal combustion engines, stirling engines, closed cycle steam engines and fuel cells. This machine has a single-stage radial compressor and turbine, a recuperator, and foil bearings. ... An internal combustion engine is an engine that is powered by the expansion of hot combustion products of fuel directly acting within an engine. ... Cut away diagram of a Rhombic Drive Beta Stirling Engine Design Pink - Hot cylinder wall Dark Grey - Cold cylinder wall (with coolant inlet and outlet pipes in Yellow) Dark Green - Thermal insulation separating the two cylinder ends Light Green - Displacer piston Dark Blue - Power piston Light Blue - Flywheels Not Shown... // The term steam engine may also refer to an entire railroad steam locomotive. ... A fuel cell is an electrochemical device similar to a battery, but differing from the latter in that it is designed for continuous replenishment of the reactants consumed; i. ...

See also

• Biogas Powerplant
• Decentralized energy (more general term that encompasses CHP)
• Distributed Generation (more general term that encompasses CHP)
• Geothermal power in Iceland
• New York City steam system
• Proposed oil phase-out in Sweden
• Trigeneration (using waste heat for cooling during the summer)
• District heating
• Organic Rankine Cycle

A biogas powerplant is a system where biogas is used to generate electricity. ... Distributed generation generates electricity from many small energy sources. ... Distributed generation generates electricity from many small energy sources. ... The Nesjavellir Geothermal Power Plant Because of the special geological situation in Iceland with the high concentration of volcanoes, geothermal energy is very often used for heating and production of electricity. ... The New York City steam system is a district heating system which carries steam from central power stations under the streets of Manhattan to heat, cool, or supply power to high rise buildings and businesses. ... Crude oil prices, 1994-2007 (not adjusted for inflation) In 2005 the government of Sweden announced their intention to make Sweden the first country to break its dependence on petroleum, natural gas and other ‘fossil raw materials’ by 2020. ... Trigeneration implies the simultaneous production of mechanical power (often converted to electricity), heat and cooling from a single heat source such as solar energy or fuel. ... District heating pipe in Tübingen, Germany District heating (less commonly called teleheating) is a system for distributing heat generated in a centralized location for residential and commercial heating requirements. ... Unlike the traditional steam Rankine Cycle, the Organic Rankine Cycle (ORC) uses a high molecular mass organic fluid. ...

References

Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 201st day of the year (202nd in leap years) in the Gregorian calendar. ... Year 2003 (MMIII) was a common year starting on Wednesday of the Gregorian calendar. ... is the 314th day of the year (315th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 201st day of the year (202nd in leap years) in the Gregorian calendar. ...

External links

• Комплексные энергетические решения
• Energy Policy Act of 2005 - sec. 1817 "Study of Cogeneration"
• www.mccree.com^{[dead link]} - Air Products and Chemicals Cogeneration Plant (Orlando, Florida)
• www.co-generationsystems.com - Industrial Co-generation Equipment Provider
• Stirling Denmark Aps - Small-scale CHP systems based on Stirling technology and renewable fuels.
• CHP in Finland:
  • High cogeneration performance by innovative steam turbine for biomass-fired CHP plant in Iisalmi, Finland (URL accessed on 30 March 2006)
• CHP in Belgium :
  • Experimental study and modeling of a low temperature Rankine Cycle for small scale cogeneration
• UK micro CHP schemes:
  • CHP at DEFRA
  • BBC News: Power from the people
  • Powergen WhisperGen^{[dead link]}
  • M.I.T. algae reactor
  • Stirling/ Oven^{[dead link]}
• Associations:
  • U.S. Combined Heat and Power Association
  • COGEN Europe The European Association for the Promotion of Cogeneration
  • The World Alliance for Decentralized Energy