Fuel cost

Utility costs vary enormously. This is especially true of fuel costs. Not only do costs vary considerably between different fuels (coal, oil, natural gas), but costs also tend to be sensitive to market fluctuations. Contractual relationships also have a significant effect on fuel costs. The price paid for fuel may depend very much on how much is purchased. 

When electricity is bought from centralized power generation companies, the price tends to be more stable than fuel costs, since power generation companies tend to negotiate long-term contracts for fuel supply. 

Steam costs vary with the price of fuel. If steam is only generated at low pressure and not used for power generation in steam turbines, then the cost can be estimated from local fuel costs assuming a boiler efficiency of around 75 percent (but can be significantly higher) and distribution losses of perhaps another 10 percent, giving an overall efficiency of around 65 percent. 

The problem with this approach is that if the steam generated in the boilers is at a very high pressure and/or the ratio of power to fuel costs is high, then the value of low-pressure steam can be extremely low or even negative. This is not sensible and discourages efficient use of low-pressure steam, since it leads to low-pressure steam with a value considerably less than its fuel value. 

The amount of land required varies as well, not only as a function of the amount of production that is anticipated, but also on the type of culture system that is used. It may take several hectares of static culture ponds to produce the same biomass of animals as one modest size raceway through which large volumes of water are constantly flowed. Constmction costs vary from one location to another. Local labor and fuel costs must be factored into the equation. The experience of contractors in building aquaculture facihties is another factor to be considered. 

A.nnual energy and fuel costs electric energy costs chiller or compressor pumps chilled water heating water condenser or tower water weE water... 

The absorber tail gas contains about 20 mol % hydrogen and has a higher heating value of ca 2420 kj/m (65 Btu/SCF). With increased fuel costs and increased attention to the environment, tail gas is burned for the twofold purpose of generating steam and eliminating organic and carbon monoxide emissions. 

MW plant and 3.3% for the 200 MW plant. Not surprisingly, the savings become less as the plant becomes smaller. The costs ia Figure 12b are based on the capital cost curve (Fig. 12a) and fuel costs based on the modified EGAS reference steam plant efficiency of 34.3%. The cost comparisons are based on a coal price of 1.00/GJ ( 1.05/MBtu). Higher fuel costs would iacrease the attractiveness of MHD because of its more efficient use of the fuel. 

Fuel costs are taken to be 1.00/GJ ( 1.05/MBtu) the escalation and interest rates are 6.5% and 10%, respectively and the factor used for calculating levelized fuel and operating and maintenance cost is 2.004. 

In the early years of reactor development, electricity from nuclear sources was expected to be much cheaper than that from other sources. Whereas nuclear fuel cost is low, the operating and maintenance costs of a nuclear faciHty are high. Thus on average, electric power from coal and nuclear costs about the same. 

Another furnace that does not require fuel preparation is the stoker boiler, which was used by New York State Electric Gas Corporation (NYSEG) in its TDE tests. At NYSEG, the stoker boiler, which has a 1649°C (3000°E) flame temperature (as does the cyclone boiler), has routinely blended low quaUty coal, and more recently, wood chips with its standard coal to reduce fuel costs and improve combustion efficiency. In the tire-chip tests, NYSEG burned approximately 1100 t of tire chips (smaller than 5x5 cm) mixed with coal and monitored the emissions. The company determined that the emissions were similar to those from burning coal alone. In a second test-bum of 1900 t of TDE, magnetic separation equipment removed metal from the resulting ash, so that it could be recycled as a winter traction agent for roadways. 

Increasing fuel costs and sizes of industrial and utiUty installations have forced the emphasis in economical considerations to shift to high thermal efficiency, rehabiUty, and avadabihty. The investment, operating, maintenance, transmission, insurance, and other costs as well as depreciation must also be considered, but these are often less important. 

In some places and under certain conditions, freshwater can be obtained more cheaply by desalination of seawater than by transporting water. This is tme when all the costs of extremely large monetary investments in dams, reservoirs, conduits, and pumps to move the water are considered. Before the rapid escalation of fuel costs between 1973 and 1980, the cost of desalination of seawater to adequately supply southern California would have been less than that of transport to the Peripheral Canal. This would have been the case even if there were an unlimited supply of water in the mountains of northern California, a condition that does not appear to exist. It has been shown that before 1973 a seacoast town could have been suppHed with 7-12 x lO" /d of freshwater more cheaply by desalination than by damming and piping water a distance of >160 km km (7). Indeed, the 1987—1992 drought in California has compelled the city of Santa Barbara to constmct a water desalination plant, and a 76,000-m /d plant is plaimed for the western coast of Florida (8). 

Hori ntalEetort. In 1800, the first commercial zinc process made use of the horizontal retort. In 1980, only three such plants remain because they are not competitive in terms of labor and fuel costs. Furthermore, the dust produced presents a serious pollution problem. Nevertheless, in 1956, the tonnage of zinc produced from horizontal retorts was above that of any previous year. The only remaining operation is in Russia with a capacity of 10,000 annual MT. 

The commercial value of a clay deposit depends on market trends, competitive materials, transportation faciflties, new machinery and processes, and labor and fuel costs. Naturally exposed outcrops, geological area and stmcture maps, aerial photographs, hand and power auger drills, core drills, earth resistivity, and shallow seismic methods are used ia exploration for clays (32). Clays are mined primarily by open-pit operation, including hydraulic extraction however, underground mining is also practiced. 

Example 17 Effect of Fuel Cost on Project Economics. 9-38... 

Dielectric dryers have not as yet found a wide field of application. Their fundamental characteristic of generating heat within the solid indicates potentialities for diying massive geometrical objects such as wood, sponge-rubber shapes, and ceramics. Power costs may range to 10 times the fuel costs of conventional methods. 

Fuel costs vaiy widely from one area to another because of the cost of the fuel itself and the cost of transportation. Any meaningful cost comparison between fuels requires current costs based on such factors as the amounts used at a particular geographical location, utilization efficiencies or energy-ratio data for the equipment involved, and the effects of Torm v ue. Although the costs given in Table 27-9 do not apply to specific locations, they give fuel-cost trends. 

A difference between these firing methods may also be manifested in the initial fuel cost. For efficient operation of a spreader-stoker-fired boiler, the coal must consist of a proper mixture of coarse and fine particles. Normally, double-screened coal is purchased because less expensive run-of-mine coal does not provide the optimum balance oFcoarse and fine material. 

A further detail of this study included sensitivity analysis for the area of heat exchangers, discount rate, and fuel cost. The results are listed in Table 3-8. Option 2, the turboexpander scheme, was selected in terms of energy and maintenance savings, as well as enhanced reliability, availability, and safety. 

Power imported from the national grid Fuel cost at. 033 S/standard m Discount rate at 10% Minimum area heat exchanger 184.33 181.00 186.83... 

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