The term cryogenics derives from the Greek kryos, for icy cold. The upper limit that characterizes the cryogenic region of the temperature scale is subjective. If the delimitation criterion takes into consideration practical reasons, then this upper limit can be established at a higher than usually declared value (120 K) in order to include natural gas fuel liquefaction. The cryogenics region of the temperature scale 0–120 K can be divided into sub regions according to the criteria of the cryogenic method and refrigerant (known as crycoolers) as follows: (more…)
The idea of using an absorption fluid as a refrigerant carrier derived from the drawback of VCR (vapor–compression refrigeration) s ...
Micro technology can be employed to produce miniaturized refrigeration and cryocooling systems. Although process intensificat ...
The issues of hydrogen storage run through the hydrogen production, hydrogen transport, supply and demand for end use of hydrog ...
n fabricating microscale energy systems, a number of operating conditions must first be taken into account. Foremost are the op ...
Many small-scale energy systems require effective miniaturized pumps and expanders. These devices are responsible for conveying ...
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 ...
At present, in the United States and worldwide, motor vehicles are fueled almost exclusively by petroleum based gasoline (or reformulated gasoline) and diesel fuels. Since the first oil price shock in 1973, efforts have been made to seek alternative fuels to displace gasoline and diesel fuels and achieve energy and environmental benefits. Some of the alternative fuels that have been researched and used are liquefied petroleum gas (LPG), compressed natural gas (CNG), liquefied natural gas (LNG), methanol (MeOH), dimethyl ether (DME), Fischer– Tropsch diesel (FTD), hydrogen (H 2 ), ethanol (EtOH), biodiesel, and electricity. Production processes associated with gasoline, diesel, and each of these alternative fuels differ. (more…)
There are different types of vehicle propulsion systems and the transportation fuels that have been studied for their potential ...
Gasoline is used mainly by cars, motorcycles, and light trucks; diesel is used mainly by heavier trucks, buses, and trains. Togethe ...
The energy efficiencies of various fuel production pathways from well to pump. The efficiencies shown are defined as the energy ...
The United States depends heavily on imported oil to fuel its transportation infrastructure. The use of alternative fuel derive ...
Most alternative fuel vehicles on the road today were originally designed for gasoline, but converted for use with an alternative f ...
The spark-ignition and compression-ignition engine and internal combustion engines technologies that are currently employed in motor vehicles were developed more than 100 years ago. These conventional vehicle technologies are fueled by petroleum-derived gasoline and diesel fuels (the socalled conventional fuels). Over the past 100 years, the conventional technologies have been dramatically improved, reducing cost and increasing performance. (more…)
ISO document 14040 identifies four areas for using life cycle analysis (LCA) results: (1) identifying opportunities to improve ...
The fuel cycle for a given transportation fuel includes the following processes: energy feedstock (or primary energy) product ...
There are different types of vehicle propulsion systems and the transportation fuels that have been studied for their potential ...
Because different studies have different system boundaries and parametric assumptions, the studies described in Section 7 resulted ...
For processes that produce multiple products, energy and emission burdens have to be allocated to individual products. ISO 14040 ad ...
Biodiesel is an ester that can be made from substances such as vegetable oils and animal fats. Biodiesel can either be used in its pure state or blended with conventional diesel fuel derived from petroleum. Vegetable oil was used as a diesel fuel as early as 1900, when Rudolf Diesel demonstrated that a diesel engine could run on peanut oil. (more…)
The United States depends heavily on imported oil to fuel its transportation infrastructure. The use of alternative fuel derive ...
In 1998, several initiatives were implemented in Brazil, aiming to introduce biodiesel into the Brazilian energy matrix. The in ...
For every 100 units of biodiesel fuel produced using this method, there are 11 units of glycerin as a by-product. Glycerin is u ...
Two factors have contributed to an aggressive expansion of the European biodiesel industry. Reform of the Common Agricultural P ...
Biodiesel is diesel fuel made from renewable sources of carbon such as used vegetable oil or animal fats used in cooking. In di ...
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 ...
As a reaction to these historical perspectives, the building industry has witnessed a certain rise in design responses to regional climatic conditions, as part of a powerful efficiency and energy conservation push since the 1970s. More recently, the zero green house gas emsission and office building has become a design concept as part of strategies to introduce urban renewable energy as an increasing contributor to managing urban energy supplies. (more…)
Hydrogen has many applications when it comes to fuel. It can be used both in internal combustion engines and hydrogen fuel cells. ...
The age of industrialization came into full force through the modern exploration and use of fossil fuels. As one of its most striki ...
The commercialization prospects for fuel cell vehicles depend not only on their performance and cost, but also on how well th ...
All of today’s hydrogen conversion products, demonstration models, and prototypes possess some deficiencies; they cannot yet pr ...
The Solar City approach originally emerged from a new generation of International Energy Agency (IEA) energy research and developme ...
The age of industrialization came into full force through the modern exploration and use of fossil fuels. As one of its most striking phenomena, the rapid expansion of cities throughout the late 19th and the 20th centuries was a direct outcome of the fossil fuel energy economy as well. (more…)
The aim is to work with cities in advancing renewable energy technologies and systems and to help promote the renewable energy indu ...
The Solar City approach originally emerged from a new generation of International Energy Agency (IEA) energy research and developme ...
In the absence of useful and established patterns of practice, a search is under way for new means of reconciling local government’ ...
As a reaction to these historical perspectives, the building industry has witnessed a certain rise in design responses to regio ...
Climate change caused by the enhanced greenhouse effect is one of the most significant global environmental issues. Increased emiss ...
Bioenergy produced from biomass is sometimes called a carbon-neutral energy source, because the same quantity of carbon released when the biomass is burned is sequestered again when the crop or forest is re-grown. Referring to bioenergy as carbon neutral or having zero net emissions may be misleading; there are emissions associated with producing biomass, such as from fossil fuel used in cultivation, harvest, processing and transport, and in manufacture and construction of fuel conversion technology. (more…)
Climate change caused by the enhanced greenhouse effect is one of the most significant global environmental issues. Increased emiss ...
The quantification of the actual reduction in green house gases sourcess emissions resulting from the substitution of fossil fu ...
To date, most discussion and research relating to the various of biomass role in mitigating CO2 emissions has been focused around i ...
The future development of energy crops, to the level at which they would replace residues as the major bioenergy fuel source, will ...
Estimation of the future technical potential of biomass as an energy source is dependent on assumptions with respect to land av ...
The global cycling of carbon involves both biological and physical processes. Only the biological components are discussed here. Plants and other photosynthetic organisms assimilate CO2 and eventually convert the CO2 to simple sugars trough sugar extraction fermentation. From simple sugars, plants synthesize a variety of compounds and store them in the form of plant tissue. (more…)
The global carbon cycle involves both biological and physical processes. Only the biological components are discussed here. Pla ...
The flux of carbon among terrestrial, aquatic, and atmospheric pools is at least partially controlled by photosynthetic process ...
The accumulation of carbon within a forest growth cycle can be considered in four stages. The initial establishment stage involves ...
Reductions in carbon intensity, C/E, the carbon emitted per unit of energy generated, reflect the degree to which societies decarbo ...
It is of interest to examine potential sources of greenhouse gases sources or atmospheric CO2 by analysis of the global distrib ...