Cogeneration,

We discuss next how improved first and second law efficiencies in the use of thermal energy can be realized through a very interesting approach, Cogeneration. 

This system is a more efficient way of using energy inputs and allows the recovery of otherwise wasted thermal energy for use in an industrial process. Cogeneration technologies are classified as 

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A more complex utility is combined heat and power (or cogeneration). Here, the heat rejected hy a heat engine such as a steam turbine, gas turbine, or diesel engine is used as the hot utility. 

The principal sources of utility waste are associated with hot utilities (including cogeneration) and cold utilities. Furnaces, steam boilers, gas turbines, and diesel engines all produce waste as gaseous c bustion products. These combustion products contain carbon... 

This is particularly important when considering the effect that combined heat and power generation (cogeneration) has on utility waste. 

Combined heat and power cogeneration). Combined heat and power generation can have a very significant effect on the generation of utility waste. However, great care must be taken to assess the effects on the correct basis. 

Increased energy efficiency. Increasing energy efficiency and the introduction of cogeneration reduce CO2 emissions. Remember that emissions should be viewed on a global basis, as discussed in Chap. 10. 

There are two parasitic reactions offsetting anode efficiency (/) cogeneration of oxygen [7782-44-7] O2, from the anodic discharge of water,... 

Includes cogenerators, small power producers, and all other sources, except electric utiUties which produce electricity for self-use or for deUvery to the grid. The generation values for nonutiUties represent gross generation rather than net generation (net of station use). 

Alternatively, short-rotation hybrid poplar and selected grasses can be multicropped on an energy plantation in the U.S. Northwest and harvested for conversion to Hquid transportation fuels and cogenerated power for on-site use in a centrally located conversion plant. The salable products are Hquid biofuels and surplus steam and electric power. This type of design may be especially useful for larger land-based systems. 

Table 34. Biomass-Fueled Cogeneration and Small Power Production Capacities and Facilities, kW ...

Biofuel Cogeneration Small power producers Total ... 

Changing the stmcture of R affects the activity of monoperoxycarbonates as previously discussed for peroxyesters. The other cogenerated radical is an alkoxycarbonyloxy radical. The nature of the R group has practically no effect on the reactivity of monoperoxycarbonates having the same 00-tert-55ky group. The 10-h half-life temperature remains at 100°C for almost ah. 00-tert-huty O-alkyl monoperoxycarbonates. 

In the United States, laws passed since the late 1970s have encouraged the development of cogeneration plants and independent power plants developed by nonutiHty power producers. Combustion-turbine-based faciHties have become extremely popular among nonutiHty power plant developers. Among the many reasons for selecting this technology is the abiHty to develop compact, modular, combustion-turbine-based power plants within one or two years. 

Conventional fossil fuel-fired power plants, nuclear power faciUties, cogeneration systems, and combined-cycle faciUties all have one key feature in common some type of steam generator is employed to produce steam. Except for simple-cycle cogeneration faciUties, the steam is used to drive one or... 

Another example of a topping cycle cogeneration system is one based on recovering the thermal energy exhausting from a gas turbine/generator. 

Gas turbine-based power plants, particularly natural gas-fired cogeneration and combined-cycle faciUties, have proven to be highly rehable, efficient, and environmentally attractive. Advances in machine design, more efficient plant integration, and optimistic forecasts for the availabiUty of affordable natural gas worldwide have boosted the appeal of these systems for both base-load and peaking service. 

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