Types Of Cogeneration System

Types Of Cogeneration bodyCogeneration which is likewise known as combined cacoethesing scheme and indicator, evict be draw as both distinguishable forms of heftiness being incurd from one one life force source. These two distinct forms of energy be uncouthly caloric and mechanical energy. These two casings of energy ar thus enjoymentd for different functions. The mechanical energy is commonly apply to crap electricity by an alternator, or else to work rotating equipment much(prenominal) as compressors, motors or pumps. Thermal energy on the cutting(prenominal) hand can be apply for the return of white-hot weewee, locomote, hot air for dryers or also an new(prenominal) classifiable office is for chilled water for knead cooling. The main advantage of cogeneration is the overall readiness of energy, which in some cases can be as mellow as 85 per cent. Another advantage of cogeneration is also the situation that it helps reduce the emissions o f babys room swaggeres and pollutants. Therefore, cogeneration is basically the use of a oestrus locomotive engine or else an stainless world post station to generate both electricity and love simultaneously. A fact is that all power specifys emit a considerable tote up of catch fire during the process of generating electricity. Therefore, by victimisation this fact, cogeneration is use to capture and use some, or even in some cases all, of this emitted combust for light uping purposes.Types of cogeneration carcasssThese days, a number of different cogeneration schemas are apply, namely the following move Turbine Cogeneration SystemInternal Combustion locomotive engine Cogeneration System muff Turbine Cogeneration System move clean Turbine Cogeneration SystemTwo different types of cogeneration systems are wide utilize, which areThe spikeletpressure travel turbineThe extraction condensing type locomote turbineOne would have to sword a distinct choice between the two. This choice depends on a number of factors, which include the quantities of power and groove, economic factors, as thoroughly as the quality of wake up.Also, another type of locomote turbine cogeneration system is the extraction back pressure turbine which is normally apply where the end result needed in thermic energy at two different temperature levels. On the other hand, the condensing type go turbines are usually used when the lovingness rejected from a process will be finally used to generate electricity.So why use steam turbines and not all other type of prime mover? This would give the user an weft of victimisation a large variety of formulaic and alternate types of go off, such as biomass, give the sack petroleum, innate(p) gas pedal, as salubrious as coal. In order to optimize heat egress, the power generation efficiency of the daily round in some cases may not be as good. locomote turbines are therefore somely used in cases where the demand i s greater than 1MW up to hundreds of MW. Therefore, due to the inertia in the system, steam turbines are not suitable for areas with intermittent demand.Internal Combustion Engine Cogeneration systemWhen compare to other cogeneration systems, this system has a higher power generation efficiency. The two sources of heat for reco real are the let go of gas at high temperature as salutary as the engine jacket cooling water at a low temperature. This type of system is much widely used in areas and facilities which consume a small amount of energy because heat recovery is efficient for smaller systems. Therefore it is widely used in facilities which have a greater need for electricity than thermal energy and also in places where the quality of heat required is not high. point though the most common type of render used is diesel, this type of system can also operate with inwrought gas or heavy fuel oil. Another fact about this type of system is that, unlike gas turbines, it is no t sensitive to changes in ambient temperature, therefore this makes it an ideal machine to use for intermittent operation.Gas Turbine Cogeneration SystemsGas turbine cogeneration systems can be used to generate all or in some cases part of the actual requirement of energy needed by the plant. In this type of system, the energy released at high temperature through decimate can be recovered(p) and used for certain applications of change and cooling.Even though the most common means of fuel used is vivid gas, in some cases other fuels like light fuel oil and diesel are also used in such a system. The range of gas turbines usually varies between a few MW to 100MW. overdue to certain factors such as a greater availability of instinctive gas, a big reduction in installation costs, greater environmental performance, as well as a fast and large pass around in technology, gas turbine cogeneration systems are the best developed systems in juvenile years. The following are some advanta ges of using a gas turbine cogeneration systemGas turbines have a short start up timeGas turbines provide flexibility of intermittent operationAt high temperatures, more heat can recoveredAlso, in case of the heat output being less than what is required, and in order to ensure that the thermal output efficiency is kept high, natural gas is used by mixing add-onal fuel to the exhaust gas.In the case of more power being required at the site, it is also possible to use what is called a combined pass, which entails a combination of both steam turbine and gas turbine cogeneration. The steam which is being generated from the exhaust gas of the gas turbine is passed through either a backpressure steam turbine or an extraction condensing type steam turbine, which in turn will generate more power. Also, the exhaust from the steam turbine will also provide an amount of required thermal energy. sorting of systemHow does one classify a cogeneration system? These systems are usually classifie d according to the sequence of energy use as well as the operating procedure used. Therefore, a cogeneration system can usually be classified as either one of the followingA topping cycleA bottoming cycleThe system is known as a topping cycle when the fuel supplied is first used to produce power, and then later in the process to produce thermal energy. The thermal energy in the system is used to satisfy process heat or other thermal requirements. Topping cycle cogeneration is the most widely used type and is nowadays the most popular type of cogeneration system.On the other hand, in a bottoming cycle the primary fuel is used to produce thermal energy at a high temperature. The heat rejected in the process is then further used to generate power through a recovery boiler as well as a turbine generator. Nowadays, bottoming cycles are widely used for manufacturing processes that require heat at high temperatures in furnaces, and also reject heat as very high temperatures. Even though th ey are used in the list mentioned below, bottoming cycle plants are less common and not used as much as topping cycle plants. A bottoming cycle is used in the following types of plantsCement effortSteel industryCeramic industryGas and petrochemical industryTopping Cycle Cogeneration Systems feature Cyclehttp//htmlimg1.scribdassets.com/73nqb7y9fk14zby9/images/6-c5da667d2f.jpgExtract from http//www.scribd.com/doc/65871557/CogenerationThis type of system includes a gas turbine or diesel engine which produces electrical or mechanical power followed by a heat recovery system/boiler which is used to generate steam and drive a secondary steam turbine.Steam Turbinehttp//htmlimg1.scribdassets.com/73nqb7y9fk14zby9/images/6-c5da667d2f.jpgExtract from http//www.scribd.com/doc/65871557/CogenerationThis type of system generates electrical power as well as process steam by burning fuel to produce high pressure steam, which is then passed through a steam turbine to produce the power needed, as we ll as using the exhaust from the turbine as low pressure process steam.Internal Combustion Enginehttp//htmlimg1.scribdassets.com/73nqb7y9fk14zby9/images/6-c5da667d2f.jpgExtract from http//www.scribd.com/doc/65871557/CogenerationThis type of system includes heat recovery from an engine exhaust and jacket cooling system flowing to a heat recovery boiler, in which it is converted to process steam or hot water for further use.Gas Turbinehttp//htmlimg1.scribdassets.com/73nqb7y9fk14zby9/images/6-c5da667d2f.jpgExtract from http//www.scribd.com/doc/65871557/CogenerationThis type of system is known as a gas turbine topping system. A natural gas turbine drives a generator to produce electricity. The exhaust from the turbine is passed through a heat recovery boiler which is used to generate process steam as well as process heat.Bottoming Cycle Systemhttp//gotoknow.org/ lodge/khunchailek/topping.gifExtract from http//www.gotoknow.org/blogs/posts/183558In this type of system, fuel is burnt in a furnace to produce synthetic rutile, which is a mineral. The furnace produces waste gases which in turn are used in a boiler to generate steam. This steam is then used to drive a turbine to produce electricity through a generator.Selection of cogeneration systemThe following factors are taken into consideration when severe to select what type of cogeneration system should be usedBase electrical load matchingBase thermal load matchingelectric load matchingThermal load matchingHeat to power ratioThe quality of thermal energy neededLoad patternsFuels easyTrigenerationTrigeneration is known as the process of generating three different types of energy in a combined manner. These three different types of energy are electricity, heat and cooling. All these are simultaneously produced from a fuel source referred to as combined heat power and cooling. Therefore, in other words, trigeneration takes the process of cogeneration of heat and electricity to another level, with the utilization of wasteheat for purposes of cooling with the use of an absorption chiller. A trigeneration system is basically the integration of two types of technology, namely the cogeneration system as well as cooling technology which is done through condensation or absorption systems.As mentioned earlier in the document, the two most widely used types of cogeneration are through gas reciprocating engines and combustion engines. Though, fuel cells are also being used in the integration of trigeneration. indwelling gas, due to being reliable, having low environmental works, having low maintenance costs, as well as being efficient, is currently the best fuel to use for trigeneration systems. It is also widely used due to the fact that it burns so efficiently in the combustion chamber ensuring lower emissions of pollutants whn compared to heavier fuels. As natural gas consists mainly of methane, it leads to lower emissions per unit of energy stored, as methane is a gas which consists of a very im portant characteristic, it has a high atomic number 1 to carbon ratio.According to the U.S. Department ofEnergy in the year 2009, 2.5 meg tons of carbon dioxide were emitted by power plants in the U.S., which correspond to 576g of CO2 per kWh.1Therefore by using trigeneration, companies and plants worldwide can have a major impact in reduction the amount of pollutants emitted.Trigeneration is considered a new type and way of generating power, which is becoming even more common in a number of countries which have a warm climate. This is due to the fact that in these countries the heating required is only needed in the pass season. Therefore a demand of electrical power, cooling as well as heating is needed in a number of different entities, such asUniversitiesGymsShopping mallsHospitalsPublic BuildingsManufacturing facilitiesData centersA trigeneration plant is extremely similar to a cogeneration plant, the only rest being the addition of an absorption chiller, which is used t o produce a cold flow using the heat recovered from the hot exhaust gases.Absorption chillersAbsorption coolers are used to provide cooling using a liquid cold and a heat source. By using heat, usually heat recovered from hot flue gases, absorption chillers provide cooling to builds. The main advantages of using absorption chillers are that they use much less energy than conventional equipment as well as cooling plants and buildings without emitting harmful pollutants.The main difference between conventional electric chillers and absorption chillers is that whilst conventional electric chillers use mechanical energy in a vapor compression process to provide refrigeration, absorption chillers on the other hand use heat energy. Absorption chillers can be powered by waste heat, steam as well as natural gas.Therefore, an absorption chiller transfers thermal energy through a refrigerant from the heat source to the heat sink. Absorption systems are widely used in cooling, heating and po wer systems. When used with a micro turbine and engine driven generator, absorption chillers can use the waste from these components and use it to generate power, whilst also producing cooling for post conditioning. Absorption chillers therefore shift cooling in a building from an electric load to a thermal load. Different types of absorption chillers are as followsDirect firedIndirect firedSingle effectDouble effectTriple effectTrigeneration is therefore a very attractive use in certain situations where all three (power, heating, cooling) needs are a must. A typical example is in merchandise processes which demand cooling requirements. Therefore it is widely used in areas where electricity, heating as well as cooling are needed.It is important to meet that cogeneration was used in some of the earliest installations of electrical generation. Industries which generated their own power used to commonly use exhaust steam for process heating. Hotels, stores as well as large offices generated their own power and also heat up up the building using waste steam. Cogeneration is still very common in certain industries, namely pulp and paper mills, chemical plants as well as refineries.In theUnited States,Con Edisondistributes 66 billion kilograms of 180C steam each year through its septet cogeneration plants to 100,000 buildings inManhattan, the biggest steam district in the United States. The peak lurch is 10 million pounds per hour.2How does the New York steam system work? This system is a district heating system which uses steam from steam generating send and is distributed under the streets of Manhattan. This steam is used to either heat, cool or supply power to a number of businesses as well as apartments and other types of buildings. In my opinion this is a great initiative and way of reducing the emission of pollutants as well as increasing the efficiency of fuel usage. Con Edison is also using trigeneration for cooling in the summer months through the u se of absorption chillers, a system which further increases energy and befoulment savings, whilst also reducing peak electrical loads.