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1.
Chimia (Aarau) ; 67(10): 732-4, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24388140

RESUMEN

The use of lignocellulosic plant material instead of food-based cereals for the production of biobased chemicals and fuels has been a matter of interest for academia and industry over the past years. The crux is the commercial viability of such processes, to be competitive in the fuels and chemicals market. Now, we are at the brink of commercialization with first processes already being implemented worldwide, offering more sustainability, energy security and economic growth.


Asunto(s)
Agricultura/métodos , Celulosa/química , Fuentes Generadoras de Energía/economía , Etanol/química , Agricultura/economía , Biocombustibles , Biomasa , Conservación de los Recursos Energéticos , Grano Comestible/química , Europa (Continente) , Industrias/economía , Industrias/tendencias , Lignina/química , Estados Unidos
2.
Nat Biotechnol ; 24(7): 765-7, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16841055

RESUMEN

A substantial increase in political and financial investment that aligns plant and industrial biotech will pay dividends for sustainable energy and materials production.


Asunto(s)
Fuentes de Energía Bioeléctrica/economía , Conservación de los Recursos Naturales/economía , Fuentes Generadoras de Energía/economía , Inversiones en Salud/tendencias , Biomasa , Celulosa/metabolismo , Conservación de los Recursos Naturales/métodos , Ambiente , Fermentación , Lignina/metabolismo
3.
Nat Biotechnol ; 24(7): 777-84, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16841058

RESUMEN

Today, ethanol and biodiesel are predominantly produced from corn kernels, sugarcane or soybean oil. But researchers and investors are increasingly upbeat about another biofuel feedstock, lignocellulose--the most abundant biological material on earth.


Asunto(s)
Biotecnología/métodos , Celulosa , Conservación de los Recursos Naturales/métodos , Fuentes Generadoras de Energía/economía , Etanol , Lignina , Residuos/análisis , Biomasa , Biotecnología/tendencias , Celulosa/química , Celulosa/metabolismo , Conservación de los Recursos Naturales/tendencias , Etanol/química , Etanol/metabolismo , Fermentación , Gasolina/economía , Lignina/química , Lignina/metabolismo , Residuos/economía
4.
Environ Sci Pollut Res Int ; 26(11): 11245-11260, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30796658

RESUMEN

This research seeks to enhance the current literature by exploring the nexus among environmental contamination, economic growth, energy use, and foreign direct investment in 6 selected sub-Saharan African nations for a time of 34 years (1980-2014). By applying panel unit root (CADF and CIPS, cross-sectional independence test), panel cointegration (Pedroni and Kao cointegration test, panel PP, panel ADF), Hausman poolability test, and an auto-regressive distributed lag procedure in view of the pooled mean group estimation (ARDL/PMG), experimental findings disclose that alluding to the related probability values, the null hypothesis of cross-sectional independence for all variables is rejected because they are not stationary at levels but rather stationary at their first difference. The variables are altogether integrated at the same order I(1). Findings revealed that there is a confirmation of a bidirectional causality between energy use and CO2 in the short-run and one-way causality running from energy use to CO2 in the long run. There is additionally a significant positive outcome and unidirectional causality from CO2 to foreign direct investment in the long run yet no causal relationship in the short run. An increase in energy use by 1% causes an increase in CO2 by 49%. An increase in economic growth by 1% causes an increment in CO2 by 16% and an increase in economic growth squared by 1% diminishes CO2 by 46%. The positive and negative impacts of economic growth and its square approve the EKC theory. To guarantee sustainable economic development goal, more strict laws like sequestration ought to be worked out, use of sustainable power source ought to be stressed, and GDP ought to be multiplied to diminish CO2 by the utilization of eco-technology for instance carbon capturing, to save lives and also to maintain a green environment.


Asunto(s)
Desarrollo Económico , Contaminación Ambiental/economía , Inversiones en Salud/economía , Cementos de Resina/economía , África del Sur del Sahara , Dióxido de Carbono/análisis , Dióxido de Carbono/economía , Estudios Transversales , Fuentes Generadoras de Energía/economía , Internacionalidad , Cementos de Resina/efectos adversos
5.
J Agric Food Chem ; 56(11): 3885-91, 2008 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-18422330

RESUMEN

Dr. Bruce Dale is the recipient of the 2007 Sterling B. Hendricks Memorial Lectureship Award. This perspective is based on a lecture given by Dr. Dale at the Life Sciences and Society Symposium at the University of Missouri on March 14, 2007, and the Award Address he presented for the Sterling B. Hendricks Memorial Lectureship Award at the 234th National Meeting of the American Chemical Society, in Boston, MA, on August 20, 2007.


Asunto(s)
Fuentes Generadoras de Energía , Brasil , Celulosa , Ingeniería Química , Costos y Análisis de Costo , Fuentes Generadoras de Energía/economía , Etanol , Abastecimiento de Alimentos , Petróleo/economía , Petróleo/provisión & distribución
6.
Trends Biotechnol ; 25(4): 153-7, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17320227

RESUMEN

Ethanol made biologically from cellulosic biomass, including agricultural and forestry residues, portions of municipal waste, and herbaceous and woody crops, is finally being widely recognized as a unique transportation fuel with powerful economic, environmental and strategic attributes. Although underfunded, it has been advanced to be competitive with corn ethanol; however, government policies are needed to overcome the perceived risk of first applications if we are to realize its societal benefits soon. Costs below those for fossil sources are foreseeable, with advances in pretreatment, enzyme production, and enzymatic hydrolysis - the steps that overcome the natural resistance of plants to biological breakdown - offering, by far, the greatest economic leverage. We must also build on the wisdom gained from past experience to avoid directing limited funds to projects that offer little new insight, could have marginal impact on commercial outcomes, or could be better improved through the power and wisdom of the learning curve.


Asunto(s)
Celulosa/economía , Celulosa/metabolismo , Conservación de los Recursos Energéticos/economía , Fuentes Generadoras de Energía/economía , Etanol/economía , Etanol/metabolismo , Política Pública , Efecto Invernadero , Estados Unidos
7.
J Air Waste Manag Assoc ; 57(8): 919-33, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17824282

RESUMEN

We examined life cycle environmental and economic implications of two near-term scenarios for converting cellulosic biomass to energy, generating electricity from cofiring biomass in existing coal power plants, and producing ethanol from biomass in stand-alone facilities in Ontario, Canada. The study inventories near-term biomass supply in the province, quantifies environmental metrics associated with the use of agricultural residues for producing electricity and ethanol, determines the incremental costs of switching from fossil fuels to biomass, and compares the cost-effectiveness of greenhouse gas (GHG) and air pollutant emissions abatement achieved through the use of the bioenergy. Implementing a biomass cofiring rate of 10% in existing coal-fired power plants would reduce annual GHG emissions by 2.3 million metric tons (t) of CO2 equivalent (7% of the province's coal power plant emissions). The substitution of gasoline with ethanol/gasoline blends would reduce annual provincial lightduty vehicle fleet emissions between 1.3 and 2.5 million t of CO2 equivalent (3.5-7% of fleet emissions). If biomass sources other than agricultural residues were used, additional emissions reductions could be realized. At current crude oil prices ($70/barrel) and levels of technology development of the bioenergy alternatives, the biomass electricity cofiring scenario analyzed is more cost-effective for mitigating GHG emissions ($22/t of CO2 equivalent for a 10% cofiring rate) than the stand-alone ethanol production scenario ($92/t of CO2 equivalent). The economics of biomass cofiring benefits from existing capital, whereas the cellulosic ethanol scenario does not. Notwithstanding this result, there are several factors that increase the attractiveness of ethanol. These include uncertainty in crude oil prices, potential for marked improvements in cellulosic ethanol technology and economics, the province's commitment to 5% ethanol content in gasoline, the possibility of ethanol production benefiting from existing capital, and there being few alternatives for moderate-to-large-scale GHG emissions reductions in the transportation sector.


Asunto(s)
Contaminación del Aire/prevención & control , Celulosa/química , Celulosa/economía , Fuentes Generadoras de Energía/economía , Etanol/economía , Etanol/aislamiento & purificación , Biomasa , Carbón Mineral , Conservación de los Recursos Energéticos/economía , Conservación de los Recursos Energéticos/métodos , Análisis Costo-Beneficio , Electricidad , Etanol/química , Ontario , Petróleo/economía , Centrales Eléctricas/economía
8.
Curr Biol ; 18(6): R225-6, 2008 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-18421806
14.
Appl Biochem Biotechnol ; 121-124: 59-70, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15917587

RESUMEN

Brazil is one of the world's largest producers of alcohol from biomass at low cost and is responsible for more than 1 million direct jobs. In 1973, the Brazilian Program of Alcohol (Proalcool) stimulated the creation of a bioethanol industry that has led to large economic, social, and scientific improvements. In the year 1984, 94.5% of Brazil's cars used bioethanol as fuel. In 2003/2004, 350.3 million of sugarcane produced 24.2 million t of sugar and 14.4 billion L of ethanol for an average 4.3 million cars using ethanol. Since its inception, cumulative investment in Proalcool totals US$11 billion, and Brazil has saved US$27 billion in oil imports. The ethanol production industry from sugarcane gene-rates 152 times more jobs than would have been the case if the same amount of fuel was produced from petroleum, and the use of ethanol as a fuel is advantageous for environmental reasons. In 2003, one of the biggest Brazilian ethanol industries started consuming 50% of the residual sugarcane bagasse to produce electrical energy (60 MW), a new alternative use of bioenergy for the Brazilian market. Other technologies for commercial uses of bagasse are in development, such as in the production of natural fibers, sweeteners (glucose and xylitol), single-cell proteins, lactic acid, microbial enzymes, and many other products based on fermentations (submerged and semisolid). Furthermore, studies aimed at the increase in the biosynthesis of sucrose and, consequently, ethanol productivity are being conducted to understand the genetics of sugarcane. Although, at present, there remain technical obstacles to the economic use of some ethanol industry residues, several research projects have been carried out and useful data generated. Efficient utilization of ethanol industry residues has created new opportunities for new value-added products, especially in Brazil, where they are produced in high quantities.


Asunto(s)
Biotecnología/economía , Biotecnología/métodos , Carbohidratos/economía , Celulosa/economía , Fuentes Generadoras de Energía/economía , Etanol/economía , Saccharum , Biotecnología/instrumentación , Biotecnología/tendencias , Brasil , Gasolina/economía
15.
Appl Biochem Biotechnol ; 121-124: 807-19, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15930560

RESUMEN

In recent years, the concept of producing biodiesel from renewable lipid sources has regained international attention. In Brazil, a national program was launched in 2002 to evaluate the technical, economic, and environmental competitiveness of biodiesel in relation to the commercially available diesel oil. Several research projects were initiated nationwide to investigate and/or optimize biodiesel production from renewable lipid sources and ethanol derived from sugarcane (ethyl esters). Once implemented, this program will not only decrease our dependence on petroleum derivatives but also create new market opportunities for agribusiness, opening new jobs in the countryside, improving the sustainability of our energy matrix, and helping the Brazilian government to support important actions against poverty. This article discusses the efforts to develop the Brazilian biodiesel program in the context of technical specifications as well as potential oilseed sources.


Asunto(s)
Biotecnología/economía , Biotecnología/métodos , Carbohidratos/economía , Fuentes Generadoras de Energía/economía , Etanol/economía , Gasolina , Saccharum , Biotecnología/instrumentación , Biotecnología/tendencias , Brasil , Celulosa/economía , Gasolina/economía
16.
Trends Biotechnol ; 22(2): 67-71, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14757040

RESUMEN

Feedstocks that deserve serious consideration for fuels and chemicals are sugarcane, corn, trees and algae. Commercialization of biomass refining is imminent but the wild claims of those who think that bioenergy can replace much of our dependence on foreign oil are appalling. It is naive to view biomass as the panacea for the coming energy crisis because there is not enough in practical locations and the costs involved in retrieving and refining it will be relatively high. The world will not run out of energy, but cheap energy might disappear, with its economics clouded by a myriad of subsidies for the competing energy sources and by world politics. This assessment of biomass supply and conversion technologies provides global perspectives and exposes some alternatives to be so impractical that they are almost fraudulent.


Asunto(s)
Fuentes de Energía Bioeléctrica/economía , Biomasa , Celulosa/economía , Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/métodos , Fuentes Generadoras de Energía/economía , Gasolina/economía , Eucariontes , Saccharum , Árboles , Estados Unidos , Zea mays/economía
17.
Biotechnol Prog ; 19(2): 254-62, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12675557

RESUMEN

Lignocellulosic biomass such as agricultural and forestry residues and dedicated crops provides a low-cost and uniquely sustainable resource for production of many organic fuels and chemicals that can reduce greenhouse gas emissions, enhance energy security, improve the economy, dispose of problematic solid wastes, and improve air quality. A technoeconomic analysis of biologically processing lignocellulosics to ethanol is adapted to project the cost of making sugar intermediates for producing a range of such products, and sugar costs are predicted to drop with plant size as a result of economies of scale that outweigh increased biomass transport costs for facilities processing less than about 10,000 dry tons per day. Criteria are then reviewed for identifying promising chemicals in addition to fuel ethanol to make from these low cost cellulosic sugars. It is found that the large market for ethanol makes it possible to achieve economies of scale that reduce sugar costs, and coproducing chemicals promises greater profit margins or lower production costs for a given return on investment. Additionally, power can be sold at low prices without a significant impact on the selling price of sugars. However, manufacture of multiple products introduces additional technical, marketing, risk, scale-up, and other challenges that must be considered in refining of lignocellulosics.


Asunto(s)
Reactores Biológicos/economía , Carbohidratos/economía , Celulosa/economía , Celulosa/metabolismo , Conservación de los Recursos Naturales/economía , Análisis Costo-Beneficio/métodos , Fuentes Generadoras de Energía/economía , Etanol/economía , Biomasa , Carbohidratos/biosíntesis , Etanol/metabolismo , Lignina/economía , Lignina/metabolismo , Estados Unidos
19.
Appl Biochem Biotechnol ; 84-86: 1147-61, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10849865

RESUMEN

Brazil is the largest producer of bioethanol, and sugarcane is the main raw material. Bioethanol is produced by both batch and continuous processes, and in some cases, flocculating yeast is used. This article analyzes the Brazilian Ethanol Program. For the 1996-1997 harvest, Brazil produced 14.16 billion L of ethanol and 13.8 million metric t of sugar, from 286 million metric t of sugarcane. These products were produced by 328 industries in activity, with 101 autonomous ethanol plants producing only ethanol, and 227 sugar mills producing sugar and ethanol. The sugar-ethanol market reaches about 7.5 billion US$/yr, accounting for direct and indirect revenues.


Asunto(s)
Fuentes Generadoras de Energía , Etanol , Plantas Comestibles , Biotecnología/instrumentación , Biotecnología/métodos , Brasil , Celulosa , Fuentes Generadoras de Energía/economía , Gasolina/economía
20.
Nat Biotechnol ; 22(6): 671-5, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15175684
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