Electricity power generation available fuels

In the U.S. a major usage of fuels is for electric power generation Q). Fuel oil is used to generate about 15% of the nation s electricity ( 1). However, it is possible with present technology along with new developments in coal combustion to reduce reliance on petroleum-based fuels by replacing them with coal. This would make more oil available to other areas such as the production of chemicals and pharmaceuticals. 

Electric power generation using biomass as a fuel is economic in situations where the cost of the fuel is competitive with that of fossil fuels. The cost of a commercially available biomass steam—electric power plant is about 1500/kW for a wood-fired facility. If wood can be obtained at a cost of 2.00/GJ ( 2.10 X 10 /Btu), the total cost of power for base-load operation would be about 0.05/kWh. If wood or agricultural wastes are available at... 

Electric Power Generation. Coal is the primary fuel for thermal electric power generation. Since 1940 the quantity of bituminous coal consumed by electric utilities has grown substantially in each successive decade, and this growth is expected to continue for many years. Coal consumed by electric utilities increased from about 536 x 10 t in 1981 to 689 x 10 t in 1989 (2). The reasons for increased coal demand include availability, relative stability of decreasing coal prices, and lack of problems with spent fuel disposal as experienced in nuclear power plants (see Nuclearreactors). 

Rankine Cycle. The sleam-Rankine cycle employing steam turbines has been the mainstay of utility thermal electric power generation for many years. The cycle, as developed over the years, is sophisticated and efficient. The equipment is dependable and readily available. A typical cycle (Fig. 21) uses superheat, reheat, and regeneration. Heat exchange between flue gas and inlet air adds several percentage points to boiler efficiency in fossil-fueled plants. Modern steam Rankine systems operate at a cycle top temperature of about 800 K with efficiencies of about 40%. All characteristics of this cycle are well suited to use in solar plants. 

Low BTU gasification technology is commercially available for most types of biomass feedstocks and can be expected to have an impact on energy supplies by 1985. Many of these commercial processes are based on low BTU coal gasification technologies and the gas produced can best be used as fuel for supplying process heat, process steam or for electrical power generation. 

OTEC power may be supplied to users by direct transmission of electricity to on-shore cnstomers at sites where deep cold water is available near shore, or nsed on-board to produce a fuel or product that can shipped ashore and stored for later use in motor vehicles or electric power plants. OTEC plantships sited on the tropical oceans will nse electric power generated onboard to electrolyze water and form hydrogen based fuels, which will be stored temporarily and then shipped to world ports at monthly intervals. 

The type of system anployed at a facility is chosen based on the loads, the availability of fuels, and the energy requiranents of the electric power generation facility. At facilities employing these systems, otha ancillary processes must be performed to support the generation of electricity. 

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