Unit cost

Initially, if operating costs can be divided based on production throughput, the satellite development project may look attractive. However, the unit costs of the declining host field will eventually exceed income and the satellite development may not be able to support the cost of maintaining the old facilities. If the old facilities can be partly decommissioned, and provision made for part of the abandonment cost, then the satellite development may still look attractive. The satellite development option should always be compared to options for independent development. 

For these reasons, CEC and DOE concluded that the only cost-effective method of getting alcohol fueled vehicles would be from original equipment manufacturers (OEM). Vehicles produced on the assembly line would have lower unit costs. The OEM could design and ensure the success and durabihty of the emission control equipment. 

The unit cost of the d-c supply decreases with increasing voltage and amperage (see Fig. 4). A chlor—alkali plant is therefore most economical when as many high amperage cells as possible are connected in series. 

The properties of fillers which induence a given end use are many. The overall value of a filler is a complex function of intrinsic material characteristics, eg, tme density, melting point, crystal habit, and chemical composition and of process-dependent factors, eg, particle-si2e distribution, surface chemistry, purity, and bulk density. Fillers impart performance or economic value to the compositions of which they are part. These values, often called functional properties, vary according to the nature of the appHcation. A quantification of the functional properties per unit cost in many cases provides a vaUd criterion for filler comparison and selection. The following are summaries of key filler properties and values. 

Use of a low temperature shift converter in a PSA hydrogen plant is not needed it does, however, reduce the feed and fuel requirements for the same amount of hydrogen production. For large plants, the inclusion of a low temperature shift converter should be considered, as it increases the thermal efficiency by approximately 1% and reduces the unit cost of hydrogen production by approximately 0.70/1000 (20/1000 ft ) (140,141). 

Capacities of maleic anhydride faciUties worldwide are presented in Table 7. The switch of feedstock from benzene to butane was completed in the United States in 1985, being driven by the lower unit cost and lower usage of butane in addition to the environmental pressures on the use of benzene. Worldwide, the switch to butane is continuing with 58% of the total world maleic anhydride capacity based on butane feedstock in 1992. This capacity percentage for butane has increased from only 6% in 1978. In 1992, 38% of the total world maleic anhydride capacity was based on benzene feedstock and 4% was derived from other sources, primarily phthaUc anhydride by-product streams. 

Mass spectrometer Manufacturers Unit cost, X 10" World market, X 10"... 

Perhaps the biggest contribution that technological advancement in petroleum production will make is bringing large volumes of unconventional petroleum resources, eg, heavy oil and tar sands, into a viable economic realm by lowering the unit cost of production. Compared to the inventory of conventional petroleum reserves and undiscovered resources, the physical inventories of such unconventional petroleum resources are extremely large for example, the Athabasca tar sands in Alberta, Canada, are estimated to contain 360 x 10 m (2250 x 10 bbl) of in-place petroleum (19). This volume is equivalent to the total inventory, ie, the combined cumulative production, reserves, and undiscovered resources, of world conventional cmde petroleum. In... 

General-Purpose Polystyrene. Polystyrene is a high molecular weight M = 2 — 3 x 10 ), crystal-clear thermoplastic that is hard, rigid, and free of odor and taste. Its ease of heat fabrication, thermal stabiUty, low specific gravity, and low cost result in mol dings, extmsions, and films of very low unit cost. In addition, PS materials have excellent thermal and electrical properties that make them useful as low cost insulating materials (see Insulation, ELECTRIC Insulation, thermal). 

Thermoforming is perhaps the process with the lowest unit cost. Examples of thermoformed articles are refrigerator-door and food-container liners, containers for dairy products, and luggage. Some of the largest formed parts are camper/trader covers and liners for refrigerated-radroad-car doors (236). 

The cost is significantly higher when all of the chlorine is replaced by chlorine dioxide because the effectiveness of the latter as a delignifying agent is considerably less than that of mixtures of chlorine and chlorine dioxide. In addition, the decreased caustic requirement is negated by the additional unit cost of off-balance caustic. 

Electrolysis. For reasons not fiiUy understood (76), the isotope separation factor commonly observed in the electrolysis of water is between 7 and 8. Because of the high separation factor and the ease with which it can be operated on the small scale, electrolysis has been the method of choice for the further enrichment of moderately enriched H2O—D2O mixtures. Its usefiilness for the production of heavy water from natural water is limited by the large amounts of water that must be handled, the relatively high unit costs of electrolysis, and the low recovery. 

It can be assumed that P,Jp, and for the cascade have been specified, and that the cost of feed and the cost per unit of separative work, the product of separative capacity and time, are known. The basic assumption is that the unit cost of separative work remains essentially constant for small changes ia the total plant size. The cost of the operation can then be expressed as the sum of the feed cost and cost of separative work ... 

The unit cost approach is widely used for quick estimates of the capital cost of utiUties, waste treatment faciUties, and buildings, where data in /kW, /t of waste, /m, etc, are available. 

Unit cost data should be carefully assessed to ensure that process type, size, and raw materials are similar to the proposed venture. Operating cost data sometimes are reported for separate categories such as operating labor, maintenance labor, supervision, and utiHties (9). 

Utihty needs should be calculated direcdy from the process material and energy balances. Unit costs for the various utihties can be obtained from suppliers or purchasing agents. Although regional variations can be quite large, typical U.S. utihty costs in 1992 are tabulated in Table 3. 

YFrC r = sum of feed flows times respec tive unit costs OC = operating costs/time... 

These unit costs, or the time taken to produce the last unit, etc., may be plotted on cartesian coordinates against the number of units produced to provide a standard against which the performance of a new employee, a new machine, etc., can be judged. Figure 9-16 shows such a plot for the subsequent example. 

The cost of an initial hatch of 21 units, exchisive of special tools and setting-iip costs, averaged 120 per unit. The average cost of the next hatch of 80 units was 75.81. Let iis establish the learning curve implied hy these data and hence estimate the probable average cost of the next 50 units. We shall establish also the unit-cost curve to be used as a control during follow-iip orders. 

The cost of the first batch is 120 X 21 = 2520, and that of the second batch is 75.81 X 80 = 6065. The total cost of the first 101 units is therefore 8585, with a cumulative-average unit cost of 85. We substitute as before to give... 

To the above costs must he added hack any unit costs omitted from those to which learning might bring improvement. These will normally include overheads and specific charges on the project such as the unit cost of special tools, jigs, etc. 

Case 3. When products 1 and 2 share the variable expenses on the basis of weight, the total contribution per Idlogram of raw material is found by substituting the unit costs into Eq. (9-197). Values for each term are... 

The percentage markup on cost is calculated for a known capital-turnover ratio and a desired rate of return on capital. As with absorption pricing, the percentage markup on manufac turing cost per unit of prodlic tion is calculated for a normal annual produc tion rate. If this produc tion rate is exceeded, the rate of return on capital will be higher than projected because of the decrease in unit cost. Conversely, if the... 

Eroduc tion rate is lower than normal, the rate of return on capital will e lower than projected because of the increase in unit cost. For production rates both higher and lower than the normal produc tion rate, the percentage markup is based on the normal unit cost. Thus the method is strictly vahd only for the normal production rate. 

Total cost Unit cost Production rate... 

Let us consider a process unit requiring heat at the rate of Qo GJ/h operating for y h in a year. We shall let the unit cost of this base heating requirement be Cg per gigajoule. Therefore the annual heating cost for this unit is Qoy s por year. 

The ratio of the unit costs of the delivered heat energy and the input energy can be obtained by combining Eqs. (9-239) and (9-240) to give... 

The annual cost of heat delivered by the heatpump is Qoy o, where the unit cost Cd is given by Eq. (9-240). Therefore, the annual saving on heating costs in dollars per year is Qoyi B d), which can also be written in terms of Eq. (9-238) as W(COP) y(cg — c ). 

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