On-site power generation

Figure 23.45 The site power-to-heat curve for complete on-site power generation in steam turbines. (From Varbanov P, Perry S, Makwana Y, Zhu XX and Smith, 2004, Trans IChemE, 82A 784, reproduced by permission of the Institution of Chemical Engineers.)... 

Distributed Generation - A popular term for localized or on-site power generation. 

Equation (2.8) can be generally applied to different scenarios for power supply such as power import, on-site power generation from back pressure and condensing steam turbines as well as from gas turbines, which are discussed in detail in Chapter 3. 

Case 2 On-Site Power Generation from Steam Turbines For on-site power generation, usually heat rate is known and it should be used as FEpower. If unknown, a typical condensing steam turbine cycle efficiency of 30% could be used to yield... 

Case 3 On-Site Power Generation from Combined Gas and Steam Turbines -When power is generated by a gas turbine (GT), gas turbine exhaust is usually sent to the heat recovery steam generator for steam generation. Steam is then used for further power generation via steam turbines. A configuration such as this is known as a gas turbine-steam combined cycle. 

Identify investment opportunities for on site power generation. 

OPTIMIZING ON-SITE POWER GENERATION VERSUS POWER IMPORT... 

Qualitatively, on-site power generation could be favorable if it is more cost-effective compared to power import and vice versa. The truth is that various steam turbines... 

Equation (19.2) converts the price ratio to the ratio of power to fuel, eaeh amount of which can be purchased with 1. The expression in equation (19.2) is the same as that of power generation efficiency and thus j ° can be called import power generation efficiency, which will be compared against on-site power generation efficiency. 

There could be several turbines in the steam system for power generation. For some turbines, there could be multiple extraction points. Each turbine extraction is a power generation path with a specific steam rate (/Wsteam,/) connects with boiler effieieney ( boiier,/)- Based on equation (15.11), on-site power generation efficiency is... 

The heat rate for on-site power generation can then be defined as... 

Introduction of power generation efficiency and heat rate for both power import and on-site power generation makes us ready to answer the fundamental question raised previously from Figures 19.4 and 19.5 Under what price ratio of fuel to power is on-site power generation more economical than power import ... 

After all, as the simplest way to conclude, on-site power generation beats power import when on-site heat rate from certain turbine flow path beats market heat rate. In this case, maximize power generation through this turbine path while observing steam balance. If possible, surplus power generated is exported to grid. 

Until now, we can safely derive the conclusion It is not always tme that maximal efficient operation is the most economical operation. It is tme only when words, the necessary and sufficient condition can be stated as When the PEE is higher than on-site power generation efficiency, the maximal efficient operating mode is also the minimal cost operating mode. Under this condition, the problem of optimizing the steam system is converted to a simplified problem to maximize the cogeneration efficiency. 

For Power Generation Subsystem Power is generated from a steam turbine (k), theoretic steam rate ( turbine k) and isentropic efficiency (turbine k)- Th isentropic efficiency depends on the inlet and outlet steam conditions and steam rate (Afturbine k)- For a given total power demand, power import can be determined from on-site power generation ... 

Stromme, Georg Coordination Prcx edures for On-Site Power Generators, Specifying Engineer, May 1977, pp. 116 119. 

In the polymer electrolyte fuel cell (PEFQ, whieh will be useful power source for automotive and on-site power generation, water management is essential because a thin polymer membrane used as an eleetrolyte in the eell shows high ionic conductivity only in hydration. A fuel eell was specially designed for MRI experiment and the hydration process of the membrane in the fuel cell was examined by time-lapse MRI to determine the water transfer coefficient. ... 

The estimated consumed power of reclaim water pumps and booster slurry pumps is supplied to the electrical engineer. Power is brought to the mining site using 10 kV or 14.6 kV overhead or underground lines. Overhead transmission lines may be of an aluminum conductor, steel reinforced (ACSR). Underground cables may be made of aluminum or copper. On-site power generation is sometimes considered. 

Solar Turbines. This San Diego based division of Caterpillar sells on-site power generation equipment. It has disclosed plans to use a "one touch" repair guarantee to assure customers of uninterrupted service. 

Furthermore, in 1996 the industry set a sector target for a 3% reduction in the total energy intensity for cement production by 2010 compared to 1990, where intensity is defined as an energy performance indicator for cement production including both thermal energy consumption for cement production and on-site power generation (excluding alternative fuels) and power consumption in the plant site. 

Absence of a grid in certain areas automatically leads to a need to install on-site power generation capacity. 

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