Bioenergy

R. Reimert and co-workers. Bioenergy 84, Vol. 3, Elsevier AppHed Science Pubhshers, London, p. 102. 

At the low end is the United States, where biomass energy accounted for only about 3 percent (2.7 quadrillion Btus) of the total energy consumption in 1997. However, biomass use had been rising over the previous five years at an average rate of about 1 to 2 percent per year, but fell in 1997 due to a warmer-than-average heating season. Bioenergy produced in the United States is primarily from wood and wood waste and municipal solid waste. 

The sources of biofuels and the methods for bioenergy production are too numerous for an exliaustive list to be described in detail here. Instead, electricity production using direct combustion, gasification, pyrolysis, and digester gas, and two transportation biofuels, ethanol and biodiesel, are discussed below. 

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. 

Another emerging area m biofuels is pyrolysis, which is the decomposition of biomass into other more usable fuels using a high-temperature anaerobic process. Pyrolysis converts biomass into charcoal and a liquid called biocrude. This liquid has a high energy density and is cheaper to transport and store than the unconverted biomass. Biocrude can be burned in boilers or used in a gas turbine. Biocrude also can be chemical by altered into other fuels or chemicals. Use of pyrolysis may make bioenergy more feasible in regions not near biomass sources. Biocrude is about two to four times more expensive than petroleum crude. 

Energy Production in the United States An Oveiview. Biomass and Bioenergy 6 161-173. 

An alternative approach to the bioconversion of sweet sorghum carbohydrates to ethanol. Biomass and Bioenergy, 8, 99-103. 

Both the intracellular and the plasma membranes are actively involved in the cell s vital functions. In the surface membranes of axons, processes of information transfer in the form of electrical signals (nerve impulses) lake place. Bioenergy conversion processes occur at the intracellular membranes of the mitochondria and chloroplasts. 

Department of Biochemistry and Great Lakes Bioenergy Research Center, University of Wisconsin, Madison, WI, USA... 

John Ralph, Department of Biochemistry and Great Lakes Bioenergy Research Center, University of Wisconsin, Madison, WI, USA Department of Biological Systems Engineering, University of Wisconsin, Madison, WI, USA and Dairy Forage Research Center, USDA-Agricultural Research Service, Madison, WI, USA... 

Because of limits on the amount of land accordingly available for growing plants that can be used for energy, bioenergy cannot be viewed globally as the sole replacement or substitute for fossil fuels, but rather as one element in a broader portfolio of renewable energy sources [1]. In rural locations in developing countries without current access to electricity, however, biomass can provide a transformative local power source. 

The current production of microalgae is mainly focused around a few species, such as Spirulim, Chlorella, Dunaliella or Haematococcus for nutritional purposes (for humans) and animal feed (especially aquaculture). Other sectors, such as cosmetics, effluent treatment and bioenergy, have shown interest, incorporating these or other species of microalgae and cyanobacteria into commercial products. Currently, 95% of the production of microalgae is based on open systems... 

The carbon footprint of electricity generation through RES (Renewable Energy Systems) are described in this section. Elydro-electricity is described first, and then wind power, followed by bioenergy systems and solar energy. 

Cherubini, F. Bird, N.D. Cowie, A. Jungmeier, G. Schlamadinger, B. Woess-Gal-lasch, S. Energy- and Greenhouse Gas-based LCA of Biofuel and Bioenergy Systems Key Issues, Ranges and Recommendations. Resou. Conser. Recy. 2009, 53, 434-447. 

For abiotic stock resources, the resource value is set as equal to the production and environmental cost for a sustainable alternative. For fossil oil, gas and coal, these alternatives are rapeseed oil, biogas and charcoal, respectively. For metal (metal ores), the production and environmental costs to upgrade low-quality ores (sustainable supplies), such as silicate minerals, to a quality similar to present day ores, using a bioenergy-driven process (near-sustainable process), is used as the resource value. 

Berndes, G. Hoogwijk, M. Van den Broek, R., The contribution of biomass in the future global energy supply A review of 17 studies. Biomass and Bioenergy 2003, 25,1-28. 

Arvelakis, S. Gehrmann, H. Beckmann, M. Koukios, E. G., Effect of leaching on the ash behavior of olive residue during fluidized bed gasification. Biomass and Bioenergy 2002, 22, 55. 

Hanaoka, T. Yoshida, T. Fujimoto, S. Kamei, K. Flarada, M. Suzuki, Y. Flatano, FI. Yokoyama, S.-Y. Minowa, T., Flydrogen production from woody biomass by steam gasification using a C02 sorbent. Biomass and Bioenergy 2005,28,63-68. 

Toci, F. Modica, G., Hydrogen production by in-situ cracking of steam-bioethanol mixtures combining electronic stimulation with chemical catalysts. In 9th European Bioenergy Conference, Chartier, Ph. Ferrero, G. L. Henius, U. M. Hultberg, S. Sachau, J. Wiinblad, M. Eds., Copenhagen, 1996, p. 425. 

Sadaka, S. S., Ghaly, A. E., and Sabbah, M. A., Two Phase Biomass Air-Steam Gasification Model for Fluidized Bed Reactors Part I - Model Development Biomass and Bioenergy, 22, 2002, pp. 439-462. 

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