Biomass energy electricity

In the United States, where clean and convenient natural gas, propane, and electricity are widely available and affordable, biomass use has limited potential. Nevenheless, U.S. biomass energy production has been increasing because of technological advances for new and improved biomass applications for electricity generation, gasification, and liquid fuels. 

In the United States about 3 percent of all electricity produced comes from renewable sources of this a little more than half comes from biomass. Most biomass energy generation comes from the lumber and paper industries from their conversion of mill residues to in-house energy. Municipal solid waste also is an important fuel for electricity production approximately 16 percent ot all municipal solid waste is disposed of by combustion. Converting industrial and municipal waste into bioenergy also decreases the necessity for landfdl space. 

Economics for generating electricity from biogas can be favorable. Landfill gas from municipal solid waste can supply about 4 percent of the energy consumed in the United States. In 1997, a total of 90 trillion Btus were generated by landfill gas, about 3 percent of total biomass energy consumption. 

Biomass gasifiers have the potential to be up to twice as efficient as using conventional boilers to generate electricity. For even greater efficiency, heat from the gas turbine exhaust can be used to generate additional electricity with a steam cycle. These improvements in efficiency can make environmentally clean biomass energy available at costs more competitive with fossil fuels. 

Besides the broad applications of electrically contacted enzyme electrodes as amperometric biosensors, substantial recent research efforts are directed to the integration of these functional electrodes as biofuel cell devices. The biofuel cell consists of an electrically contacted enzyme electrode acting as anode, where the oxidation of the fuel occurs, and an electrically wired cathode, where the biocatalyzed reduction of the oxidizer proceeds (Fig. 12.4a). The biocatalytic transformations occurring at the anode and the cathode lead to the oxidation of the fuel substrate and the reduction of the oxidizer, with the concomitant generation of a current through the external circuit. Such biofuel cells can, in principle, transform chemical energy stored in biomass into electrical energy. Also, the use... 

Utilities-Electricity Wind Generation Contract Power Generation Competitive Supply Biomass Energy LNG Terminals... 

Electrochemical properties. Applied Catalysis B Environmental 74 337-350 Athanasiou C, Coutelieris F, Vakouftsi E, Skoulou V, Antonakou E, Mamellos G and Zabaniotou A, (2007). From biomass to electricity through integrated gasification/SOFC system-optimization and energy balance. International Journal of Hydrogen Energy, 32(3) 337-342... 

Haq, Z. Biomass for Electricity, Energy Information Administration, U.S. Department of Energy Washington, DC, 2002. 

B. Net Energy Analysis of Terrestrial Biomass and Electricity Production... 

A Study of Carbon Dioxide Mitigation Effect by Biomass Energy Plantation for Electricity and Methanol... 

Until now, prices offered by local utilities were not considered attractive by producers (around US 28/MWh, 2000 US, for long term contracts and US 6,5/MWh for short-term contracts). There is not yet legislation to improve biomass-origin electricity generation. The purchase of this energy by the utilities is not mandatory and special discounts (up to 100%) on wheeling tariffs are available only for electricity from small hydro. 

The corresponding O C ratio is 1.16, taking into account that the only oxygen introdnced in the reaction is in the form of air. The energy efficiency of the process, defined as the ratio of prodnced syngas power to the chemical power of the initial biomass and electric power consnmption, is about 70%. The product temperature is about 850° C and can be recuperated. 

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