Power plant definition

An important field of study for power plants is that of the combinedplant [ 1 ]. A broad definition of the combined power plant (Fig. 1.5) is one in which a higher (upper or topping) thermodynamic cycle produces power, but part or all of its heat rejection is used in supplying heat to a lower or bottoming cycle. The upper plant is frequently an open circuit gas turbine while the lower plant is a closed circuit steam turbine together they form a combined cycle gas turbine (CCGT) plant. 

As an illustration, suppose the surface of water in a reservoir is 500 ft above the level of the site of a power plant and that there is available a flow of 200 ft3/s. In this case, H = z = 500 ft and P = 62.4 x 200 x 500 = 6,240,000 ft lb/s, or 11,340 hp, which is the total power available. If in the pipeline the friction loss is hf = 25 ft, then the power lost by friction is Whf and is seen to be 567 hp. Again, suppose a nozzle discharges 50 lb of water per second in a jet with a velocity of 120 ft/s H = V2/2g = 224 ft. Then the available power in the jet is 50 x 224/550 = 20.3 hp. The expression power equals force applied times velocity of the point of application of the force cannot be used in the preceding case, because it has no physical significance, as there is no force applied to anything, nor is there any point of application. In the case of a jet, the force it might exert would depend upon what happened when it struck an object, and the power produced would depend upon the velocity of the object. But the available power of the jet is a definite quantity, no matter what it acts upon or whether it ever acts upon anything. 

Summers, W.A. (2003), Interim Project Report, Task A.l, Nuclear Hydrogen Plant Definition, NERI Project 02-0160, Centralized Hydrogen Production from Nuclear Power Infrastructure Analysis and Test-case Design Study, WSRC-TR-2003-00484, Savannah River Technology Center, Aiken, SC, USA. 

In Table 5.2 I have compared the features of traditional fossil and nuclear power plants with those of this solar-hydrogen power plant of the future. This comparison shows that BAU (business as usual) technology is inferior even in the short run. This data shows that there is no clean fossil or safe nuclear power and that mankind must fully convert to a renewable energy economy, in the shortest possible time, but definitely not later than the end of this century. 

Hydro power systems utilise the energy of flowing water for the production of electricity. A general consensus for the definition of small hydro power plants does not exist. The upper power limit varies from 2.5 to 25 MW, depending on the country, but 10 MW is the most acceptable one and has been proposed by the European Small Hydro Association (Thematic Network on Small Hydro Power, 2005). 

A mixture of methane, ethane, and argon at 25 C is burned with excess air in a power plant boiler. The hydrocarbons in the fuel are completely consumed. The following variable definitions will be... 

Although the increase was statistically significant (p 0.001), it cannot definitely be attributed to PCBs because the workers were exposed to other chemicals in the refinery. Mortality from malignant melanoma appeared to increase with cumulative exposure and latency among electric utility power plant... 

Another "apples and oranges" comparison can arise when risk assessments have been performed on two or more putative alternatives, for example construction and operation of "conventional" versus "renewable energy" electric power plants. Even If the same risk measure Is used In each case, little Is gained In their comparison If the alternatives are not equivalent (or different) In some well-defined way. Changing the definition of equivalence may alter any conclusions to be drawn from a risk assessment. 

Sources of pollution vary from smaU-scale businesses, such as dry cleaners and gas stations, to very large-scale operations, such as power plants and petrochemical facilities. The effluent streams of industry are particularly noticeable because of their large volumes [1]. Sources include both point-source and non-point-source pollution. Point-source pollution can be traced directly to single outlet points, such as a pipe releasing into a waterway. Non-point-source pollutants, on the other hand, such as agricultural run-off, cannot be traced to a single definite source. The emissions from both span a wide range of gas, liquid, and solid compounds. 

Loppi and Nascimbene (1998) obtained the lowest values according to the Index of Atmospheric Purity (lAP) for an area which encompasses the geothermal power plant, up to a distance of about 500 m. The overall pattern of rising lAP values with the decrease of distance from geothermal power plants was definitely related to air contamination by geothermal installations. This pollution was the major cause of the observed zonation of lichen communities. H2S was assumed to be the major contaminant responsible for lichen decline around geothermal power plants. 

A pump or compressor does work on a fluid in order to increase the fluid s pressure, elevation, velocity, or internal energy. A fluid engine or turbine extracts work from a fluid by lowering its pressure, elevation, velocity, or internal energy. These definitions are the reverse of each other, so some devices could serve as pumps or as fluid engines, depending on what way they were run. Tidal power plants and pumped storage power plants use the same device as a pump for part of the day and as a turbine for another part of the day. 

Although the data for Hinkel Reservoir are definitive for a significant contribution from coal combustion, the source may not solely be power plants as we originally hypothesized. Significant contributions may have come firom two zinc smelters located adjacent to each other, both operated within about 10 km northwest of the Hinkel Reservoir site (Fig. 1). These facilities... 

Safety systems for Nuclear Power Plants are governed by strong requirements, which cannot be fulfilled by products designed for normal industrial applications. That s why in all countries, safety classified systems and non-safety classified systems for NPPs use different technologies even if the classification standards give several definitions and gradations for systems. 

After the declaration to the French National Assembly on 19 June 1997, of the decision to finally shut down the Creys power plant, and after 6 months of alternating hopes and disappointments as to a possible restart in order to complete the use of the 1st core, and perhaps even the 2" core, the first structured strategic reflection for definitive shutdown began in February 1998. One of the main aims of this reflection was to prove the technical feasibility of this dismantling based on the assumption of reasonable costs and time limits. In this context of technical doubt, fuelled by the media, a very determined attitude had to be adopted. 

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