Reductions in carbon intensity, C/E, the carbon emitted per unit of energy generated, reflect the degree to which societies decarbonize their energy sources. The long-term trend has been a shift from coal to oil to natural gas––hydrocarbons with decreasing C/H ratios emitting progressively less CO2 per joule. However, the increasing use of clean low-carbon fuels is not sustainable without somehow disposing of excess carbon because it opposes the trend in the abundance of fossil fuels, with coal resources being the most abundant followed by oil and gas. (more…)
The global cycling of carbon involves both biological and physical processes. Only the biological components are discussed here. Pl ...
The flux of carbon among terrestrial, aquatic, and atmospheric pools is at least partially controlled by photosynthetic process ...
It is of interest to examine potential sources of greenhouse gases sources or atmospheric CO2 by analysis of the global distrib ...
Climate change caused by the enhanced greenhouse effect is one of the most significant global environmental issues. Increased emiss ...
The global carbon cycle involves both biological and physical processes. Only the biological components are discussed here. Pla ...
Air-blown circulating fluidized bed gasifiers are of interest because they produce a good quality, low calorific value (LCV) gas (4–6 MJ/Nm 3 ) and possess a very high carbon conversion efficiency while allowing high capacity, good tolerance to variations in fuel quality, and reliable operation. The high and homogeneously distributed temperatures and the use of particular bed materials, such as dolomite, favor tar cracking. Successful tar cracking can also be achieved using secondary circulating fluidized bed reactors. Also, successful tests on catalytic tar cracking have been performed, for example, by introducing nickel compounds into the gasifier. Sulfur control is made easier because of the significant reduction that can be achieved by adding limestone or dolomite to the gasifier bed. (more…)
The moisture content of the feedstock affects the gas composition and the energy balance of the process since gasification is an en ...
Thermo chemical processing of biomass yields gaseous, liquid, and solid products and offers a means of producing useful gaseous ...
A combination of legislation and technology has helped clean up many of the world’s coal-burning plants. Both developed and develop ...
Biomass Storage Biomass storage is required to ensure the continuous operation of the facility. To limit the space required for ...
Gasification is a thermo chemical process that has been exploited for more than a century for converting solid feedstocks to ga ...
In Europe, modern renewable energy sources technologies were explored thoroughly for the first time after the oil embargo/ price crisis of 1973. Notably, market introduction of renewable energy technology started in about 1985, but the renewable energy sources industry has become vital only during the past decade. Accordingly, relevant statistical renewable energy sources data have been systematically compiled only over the past decade, although reliable and consistent statistical renewable energy sources data, collected since 1989, exist for all 15 countries of the European Union and for Western Europe (defined here as the EU-15 plus Switzerland, Norway, and Iceland). (more…)
There are various and somewhat complementary reasons to foster the growth of renewable energy sources in Europe. A major incent ...
The development of the ‘‘new’’ wind and solar technologies is of great importance for the future contribution of RESs to energy sup ...
Although technology change (usually involving an improvement in energy efficiency) is not inherently a geographic process, it does ...
The energy that people use every day comes from many different sources. The resources are divided into two main groups: renewa ...
Renewable energy sources cannot run out and causes so little damage to the environment that its use does not need to be restric ...
Gasification is a thermo chemical process that has been exploited for more than a century for converting solid feedstocks to gaseous energy carriers. The first gasifier patent was issued in England at the end of the 18th century and producer gas from coal gasification was mainly used as lighting fuel throughout the 19th century. At the turn of the 20th century, the main use of producer gas, obtained essentially from coal, switched to electricity generation and automotive applications via internal combustion engines. The use of producer gas was gradually supplanted by the use of higher energy density liquid fuels and as a result confined to areas with expensive or unreliable supplies of petroleum fuels. (more…)
The product gas can be burned in boilers to generate heat and raise steam, in internal combustion engines to generate electricity a ...
Thermo chemical processing of biomass yields gaseous, liquid, and solid products and offers a means of producing useful gaseous ...
Biomass Storage Biomass storage is required to ensure the continuous operation of the facility. To limit the space required for ...
Estimation of the future technical potential of biomass as an energy source is dependent on assumptions with respect to land av ...
The moisture content of the feedstock affects the gas composition and the energy balance of the process since gasification is an en ...
The fuel cycle for a given transportation fuel includes the following processes: energy feedstock (or primary energy) production; biomass feedstock transportation and storage; fuel production; fuel transportation, storage, and distribution; and vehicle operations that involve fuel combustion air or other chemical energy conversions. The processes that precede vehicle operations are often referred to as the well-to-pump (WTP) stage, the vehicle operations are referred to as the pump-to-wheels (PTW) stage, and the entire fuel cycle is referred to as the well-to-wheels (WTW) cycle. Various models have been developed that allow researchers to conduct fuel cycle analyses of vehicle/fuel systems. The GREET (greenhouse gases, regulated emissions, and energy transportation) model, developed by Argonne National Laboratory, is in the public domain and, so far, more than 1000 users worldwide have used the model to predict the energy use and emissions associated with alternative fuels vehicles. The GREET model and its documents are posted on the Internet at http:// greet.anl.gov. (more…)
The spark-ignition and compression-ignition engine and internal combustion engines technologies that are currently employed in ...
Because different studies have different system boundaries and parametric assumptions, the studies described in Section 7 resulted ...
ISO document 14040 identifies four areas for using life cycle analysis (LCA) results: (1) identifying opportunities to improve ...
It shows Well-to-Wheels Greenhouse Gas emissions of the 23 vehicle/fuel systems. For each system, the bottom bar represents CO2 ...
The combination of well-to-pump results and the energy use and emissions associated with vehicle operation (also called the pum ...
Thermo chemical processing of biomass yields gaseous, liquid, and solid products and offers a means of producing useful gaseous and/or liquid fuels. Biomass gasification is a total degradation process consisting of a sequence of thermal and thermo chemical processes that converts practically all the carbon in the biomass to gaseous form, leaving an inert residue. The gas produced consists of carbon monoxide (CO), hydrogen (H2), carbon dioxide (CO2), methane (CH4), and nitrogen (N2) (if air is used as the oxidizing agent) and contains impurities, such as small char particles, ash, tars, and oils. The solid residue will consist of ash (composed principally of the oxides of Ca, K, Na, Mg, and Si) and possibly carbon or char. (more…)
The moisture content of the feedstock affects the gas composition and the energy balance of the process since gasification is an en ...
Air-blown circulating fluidized bed gasifiers are of interest because they produce a good quality, low calorific value (LCV) gas (4 ...
Biomass Storage Biomass storage is required to ensure the continuous operation of the facility. To limit the space required for ...
Gasification is a thermo chemical process that has been exploited for more than a century for converting solid feedstocks to ga ...
A combination of legislation and technology has helped clean up many of the world’s coal-burning plants. Both developed and develop ...
Agricultural and forestry residues provide the largest proportion of biomass used for the production of biomas bioenergy. Some estimates suggest that globally available biomass role in the form of recoverable residues represents about 40 Ejyr -1, enough to meet 10% of the total present energy use of 406 Ejyr -1 . However, realizing this potential is limited by factors such as ease and cost of recovery and environmental concerns relating to sustainable land use practices. (more…)
Estimation of the future technical potential of biomass as an energy source is dependent on assumptions with respect to land av ...
The quantification of the actual reduction in green house gases sourcess emissions resulting from the substitution of fossil fu ...
Bioenergy produced from biomass is sometimes called a carbon-neutral energy source, because the same quantity of carbon released wh ...
To date, most discussion and research relating to the various of biomass role in mitigating CO2 emissions has been focused around i ...
Another large source of renewable carbon supplies is waste biomass. It consists of a wide range of materials and includes munic ...
The accumulation of carbon within a forest growth cycle can be considered in four stages. The initial establishment stage involves low global carbon cycle accumulation and may even experience net carbon loss (particularly from soil) as a result of site preparation and low biomass and bioenergy inputs. A rapid uptake of carbon is then experienced during the second phase, known as the full vigor stage, which subsequently levels off as the stand reaches the mature stage. Finally, the forest reaches old growth and the carbon is in steady state with accumulation associated with new growth balanced by mortality and disturbances. (more…)
Climate change caused by the enhanced greenhouse effect is one of the most significant global environmental issues. Increased emiss ...
To date, most discussion and research relating to the various of biomass role in mitigating CO2 emissions has been focused around i ...
The quantification of the actual reduction in green house gases sourcess emissions resulting from the substitution of fossil fu ...
Bioenergy produced from biomass is sometimes called a carbon-neutral energy source, because the same quantity of carbon released wh ...
The global cycling of carbon involves both biological and physical processes. Only the biological components are discussed here. Pl ...
Do we have the resources? Rudolf Diesel developed the diesel engine which ran on biodiesel vegetable oil in the late 1800s. At the time, he speculated that his discovery seemed insignificant, but later could prove to be as important as mankind’s uncovering of future energy uses for petroleum and coal tar. Given the U.S.’ rapid expansion into biofuels, it would appear his vision was correct due to the drawbacks of biofuels. But widespread adoption of biomass-based fuels is not a foregone conclusion. Two questions haunt its progress. First, will it truly reduce U.S. reliance on fossil fuels? And second, is there enough farmland to accommodate widespread production, without jeopardizing food supplies? (more…)
Biofuels are made from living matter, plant or animal, and are strongly favored by agricultural interests because of the large ...
We had expressed our disagreement with Biofuels and tell them also that the European Union also wants to distance themselves from t ...
At present, in the United States and worldwide, motor vehicles are fueled almost exclusively by petroleum based gasoline (or re ...
One of the main benefits from future use of biofuels would be the reduction of greenhouse gases compared to the use of fossil f ...
Transportation is another sector that has increased its relative share of primary energy use. This sector has serious concerns ...
The future development of energy crops, to the level at which they would replace residues as the major bioenergy fuel source, will be largely dependent on regional factors such as climate change and local energy requirements and emission factors, which will determine their environmental and financial viability. (more…)
Estimation of the future technical potential of biomass as an energy source is dependent on assumptions with respect to land av ...
Bioenergy produced from biomass is sometimes called a carbon-neutral energy source, because the same quantity of carbon released wh ...
Advances in biomass feedstock production are extremely important. These advances have the potential for reducing the final cost ...
Over the last decade, the number of countries researching the potential of biomass and bioenergy for energy services rose rapid ...
The accumulation of carbon within a forest growth cycle can be considered in four stages. The initial establishment stage involves ...