Turbine cycle heat rate calculation linkedin slideshare. Microturbines operate at high rotational speeds of up to 60,000 revolutions per minute. Coalfired power plant heat rate improvement options, part 1. The turbine is operational since 1968, therefore an efficiency assessment can highlight its present technical condition. A means of measuring cycle heat rate having been defined, consideration can now be given to variations between the design heat rates quoted by the turbine manufacturers and the heat rates achieved in operation. Steam turbines are one of the most versatile and oldest prime mover technologies still in general production used to drive a generator or mechanical machinery. The choice between backpressure turbine and extractioncondensing turbine depends mainly on the quantities of power and heat, quality of heat, and economic factors. It is not mechanically connected to the gas generator, but instead is mechanically coupled, 1. Steam turbine heat rate presentations on authorstream. A socalled combined cycle unit is effectively a steam power plant, but a heat recovery steam generator hrsg is heated by gas turbine exhaust, rather than by burning fuel. This paper is an experimental and numerical study of the performance of steam cycle of a 210mw thermal power.
Effect of condenser backpressure on power plant heat rate. Th e turbine actual steam rate is the quantity of steam required by the turbine to develop the output power requirements in units of poundshorsepower hour lbhphr. An electric motor consumes 100 watts w of electricity to obtain 90 watts of mechanical power. Updating thermal power california energy commission. Consider a steam cycle with single reheat and regenerative feedheating, shown in fig 1.
The two types of steam turbines most widely used are the backpressure and the extractioncondensing types fig. The steam turbine is a form of heat engine that derives much of its improvement in thermodynamic efficiency from the use of multiple. Implement combined heat and power in the electric sector. The efficiency of nuclear plant is little bit different. These include equipment degradation, controllable parameters and system dispatch. Stag combinedcycle power generation system features table 2. Ge gas turbine performance characteristics ge power systems ger3567h 2 mechanical drive gas turbine ratings model year iso rating iso rating heat heat mass mass exhaust exhaust continuous continuous rate rate flow flow temp temp kw hp btushphr kjkwh lbsec kgsec degrees f degrees c. Plant heat rate is a measure of the combined performance of the gas turbine cycle, the steam turbine cycle, and any other associated auxiliaries.
Extraction condensing turbine an overview sciencedirect. Steam turbine performance 3 4 2 1 46 45 44 43 42 41 43 42 41 40 39 % % 1. A steam turbine is captive to a separate heat source and does not directly convert fuel to electric energy. Steam turbines are widely used for combined heat and power chp applications in the united states. Good now lets continue with a answering your question with a little bit of modification. Figure 1 is an illustrative exhaust loss curve for a condensing steam turbine. Because power is the rate of energy utilization, efficiency can also be expressed as a power ratio.
Plants with low heat rates are more efficient, consume less fuel, cost less to operate, and produce fewer emissions than higher heat rate plants. Heat rate is the heat energy input per unit of electrical energy output, or fuel consumption rate for specific levels of power plant output. Heat rate basics industrial wiki odesie by tech transfer. Even at best boiler efficiency, unit heat rate can be worse by 10% due to high steam demand. The energy is transferred from the boiler to the turbine through high pressure steam that powers the turbine and generator. A simplified way of viewing your net turbine heat rate nthr is to sum the enthalpy increases of the feedwater and the cold reheat steam across the boiler boundary and divide this by the gross. Performance monitoring is an essential tool for overall. The following calculation procedures have been provided in this section. Ger3582e steam turbines for stag combinedcycle power systems. Its modern manifestation was invented by charles parsons in 1884. Heat rate 3600 kjkwh if 100% heat energy could be converted into electricity. Understanding coal power plant heat rate and efficiency. Performance analysis of a steam turbine power plant at part load conditions article pdf.
Energy performance assessment of cogeneration and turbine bureau of energy. Ger3574g ge combinedcycle product line and performance. What is heat rate of turbinecycle heat rate is the heat input requiredper unit of power generated, forspecific fuel being fired and specificsite conditions. A lower heat rate indicates a more efficient system. Steam turbine gets heat energy in the form of superheated steam from steam generator. Pdf performance analysis of a steam turbine power plant. For a conventional fired steam generator, one can assume a desired steam flow rate and exit gas temperature and then fire the necessary amount of fuel to meet the steam demand. Calculating steam flow given steam conditions and power for directions. California average annual natural gasfired heat rates for 2001. The first steam turbine used for power generation was invented in 1884. Efficiency of energy conversion 57 illustration 41.
Combined heat and power technology fact sheets series. Beyond the turbine end of the gas generator is a freely rotating turbine. On the steam turbine side they use the rankine cycle with steam temperature at saturation point. Thats one reason why steam turbines were quickly adopted for powering ships, where space was very limited. Calculating steam turbine power given steam conditions and flow. Steam and water leakages within the turbine cycle do not affect the meas urement of heat rate, but these leakages can cause a significant loss in the actual heat. Th e typical singlestage, general purpose, back pressure turbine effi ciency range is between 30 to. Even best run units have potential for heat rate improvement.
Analysis of heat rate improvement potential at coalfired. Combined cycle units have the lowest, or most efficient, heat rate of all power generators at full power. A steam turbine is a device that extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft. Though it sometimes shows c for temperature, it will calculate as if your input was in f. Steam at 500 lb flows through the turbine each hour during normal. Turbine heat rate and efficiecy vacuum hvac scribd. Steam turbine heat recovery steam generator condenser. In 2010, epri published the steam turbine performance engineers guide 1019657, which describes the functions and. A steam turbine is also much more compact than a steam engine. In this paper, an attempt has been made to justify the operating turbine heat rate of. Pdf performance analysis of a steam turbine power plant at. Calculate the heat rate if steam enters a turbine at 400 o f at atmospheric pressure and leaves the turbine at 200 o f. The rate of runningup should be on the level 250300 revmin2.
April 2016 page 8 of 31 factors effecting optimum heat rate there are three 3 main areas that need to be considered when evaluating heat rate. The heat effects of phase transitions boilingcondensing can be quite large and for a pure substance take place at a constant temperature the choice for a certain design is based on 3 things. Doe steam turbine calculator uses units of psig and f. This may include more than one gas turbine and steam turbine. Main steam and reheat steam inlet parameters turbine. Steam turbine portfolio overview digital asset management. The steam turbine is just one cost component in a complete chp plant. Achievable level of performance of a unit could be better than design \ guaranteed on account of margins. The performance of the steam turbine is governed by the losses occurred in it. Optimising process operating conditions can considerably improve turbine water rate, which in turn will. In certain cases, the efficiency of individual components like steam turbine is addressed specifically where performance deterioration is. In addition, a control system is needed and emission reduction hardware may be required depending on local air quality requirements. Heat rate formula steam turbine definition, formula and.
Types of steam turbine an overview sciencedirect topics. Ge combinedcycle product line and performance ge power systems ger3574g 1 table 1. Any other relevant data, such as anticipated capacity factor, or a weighting of various anticipated load points, should be specified to the turbine designer in requests for quotations. Energy release in a nuclear fission is extremely high, and very small amout of it goes to heat up the steam.
Hga excess air discharge flue gas temperature main steam condition reheat back pressure lhv. Heat rate can be further divided to compare units at the same plant, where you might compare power block 1 to power block 2. The table below shows data from a unit in which the steam temperatures were lower than desired, while both main steam and hot reheat steam attemperating sprays were in. Oct 21, 2011 turbine cycleperformance calculation 1. The condensing steam turbine is a conventional steam turbine in which the steam exiting the turbine exhaust is condensed to provide the maximum energy capture. It is defined as heat energy used by the turbine cycle to generate one unit of electrical energy. Hp cylinder efficiency, steam turbine heat rate, turbine heat rate by. Turbine loses and irreversibilities are minimum and performance and power generation are maximum at design conditions.
Thermoeconomic analysis of a onepressure level heat. Heat rates are a primary input for thermal power plants in production cost model s. Turbine cycle heat rate gtchr test on steam turbine. Rh is heat rate in btuhr, w s is steam flow in lbhr, c specific heat capacity in btulb. Steam turbine, energy performance, efficiency assessment, heat balance 1 introduction the steam turbine converts the thermal energy of. Ge power systems gas turbine and combined cycle products. Steam turbine, energy performance, efficiency assessment, heat balance 1 introduction. One of the measurements of success is improved turbine heat rate. Ger3582e steam turbines for stag combinedcycle power. This is the type of steam turbine that will be used in a bottoming cycle chp plant in which waste heat or energy from an industrial process is used to raise steam to generate electricity. Stag combinedcycle thermal energy and power system features high thermal efficiency low installed cost fuel flexibility wide range of gas and liquid fuels.
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