Costs electrical power

Worldwide primary aluminum capacity. Table 14 (35), continues to grow but mosdy in countdes where there is low cost electric power. Primary capacity in the United States, Table 15, has been reduced from 5,019 thousand metric tons in 1982 to 3,902 thousand metric tons in 1988. The United States and other developed countries are expected to concentrate mote on converting taw aluminum into high value added products. 

For the areas that do have sufficiently low-cost electric power, the furnaces are constructed with conventional bottoms hut with superstructure only adequate lor initial heat-up. They depend on a blanket of hatch floating on the surface of ihe glass to retain the heat within the tank that is provided by the submerged electrodes. Fresh batch is added to the blanket at a rate equal to the rate of melted glass withdrawn. 

A small but growing photovoltaic industry now exists with worldwide sales between 300 million and 400 million. The United States and Japan account for 75% of worldwide sales, but European firms are increasingly active, with over 17% of the market [9]. Panel prices are about 5 per peak watt. With this capital cost and today s attendant equipment costs, electric power can be generated for between 30 and 40 cents per kilowatt-hour. 

Development of other non-fossil fuel energy sources, such as geothermal, solar, wind and ocean thermal systems will undoubtedly broaden the scope of application for electrolytic hydrogen — perhaps not because they represent a source of low cost electrical power, but because it represents the most attractive means for providing a transportable fuel from these renewable resources. 

With the rapid acceptance of the Hall-Heroult electrolytic method of aluminum production, facilities using this process have tended to be constructed in areas with abundant, low-cost electric power (Table 12.2). In addition, to minimize shipping costs it is usual to process bauxite ore to purified alumina at the mine site for shipment to smelters (Table 12.2). Thus, aluminum smelters are sited so as to provide easy shipping access for economical alumina delivery from the mine. The production of aluminum from bauxite logically can be considered in two steps the first, production of high-purity alumina from the working of natural bauxite deposits, and the second, electrolytic reduction of alumina to the metal. 

Insurance Variable cost Electric power Natural gas price... 

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. 

Cooling water costs tend to be low relative to the value of both fuel and electricity. The cost of cooling duty provided by cooling water is on the order of 1 percent that of the cost of power. For example, if power costs 0.07 kW h, then cooling water will typically cost 0.07 X 0.01/3600 = 0.19 x 10 kJ or 0.19 GJ L... 

The abrasive industry is highly competitive and many small companies worldwide successfully compete by specializing in a particular segment of the business, eg, disk wheels, mounted points, and mbber wheels. Costs in the fused abrasive industry are primarily in materials and electric power. Thus manufacturers seek out plant sites having the lowest power costs. Costs for coated abrasive manufacturers are capital and labor intensive and they seek out sources of low cost labor. 

Induction heating equipment installations can require significant investment in electric power components as well as the work handling equipment made necessary by the process. These costs can be offset by savings in plant space, reduction in metal loss, precise control of product temperature, and reduced in-process inventory. A typical continuous induction heating line consumes about 360 kW h/t heating carbon steel bars to 1230°C. 

Normal ceU voltages are ca 0.2 V. The power consumption is correspondingly very smaH, and electrorefining is much less sensitive to the cost of electric power than other electrometaHurgical processes. When a diaphragm is used to separate the anodic and cathodic solutions, the ceU voltage increases up to ca 1.2 V, and the power consumption rises accordingly. 

A simple, low cost steel for high temperature service in electric power generation (qv) is the C—0.5% Mo steel known as carbon—half moly, which was widely used for many years. The power industry and oil refineries have turned to 1.25% Cr—0.5% Mo and 2.25% Cr—1% Mo steels for high stress and high temperature service, because these steels have improved resistance to graphitization and oxidation, as weU as higher creep and mpture strength. 

---