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 ...
Drying is one of the most important post harvest steps. It enhances the storage life of the crop products, minimizes losses during storage, and saves shipping costs. The drying process is the removal of water from the wet surface of the food. In this process, heat is transferred by convection and radiation to the surface of the produce. This heat raises the temperatures heat and evaporates the moisture from the exterior of the agricultural products, diffusing the interior moisture to the surface and replenishing the evaporated surface moisture. (more…)
Solar dryers are special structures that enhance the drying power of the sun and protect the agricultural product from dust, dirt, ...
The moisture content of the feedstock affects the gas composition and the energy balance of the process since gasification is an en ...
Biomass Storage Biomass storage is required to ensure the continuous operation of the facility. To limit the space required for ...
As a result of high and rising costs of fossil fuels and fossil fuels affect global environment concern , and by the reduction ...
Solar distillation is the process in which solar heat is used to purify water from an impure water source by evaporation and conden ...
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 ...
Fuel cell vehicles are being developed because they promise to meet the requirements expected of automobiles in a market increasingly constrained by environmental and resource limitations. Air pollution and oil dependence have been persistent challenges for vehicles powered by petroleum fuels (gasoline and diesel). Global warming presents a new challenge in the need to limit carbon dioxide (CO) emissions from fossil fuel combustion. (more…)
There are different types of vehicle propulsion systems and the transportation fuels that have been studied for their potential ...
The internal combustion engine has dominated the car and light-truck market for over 100 years. Although remarkable improvement ...
The commercialization prospects for fuel cell vehicles depend not only on their performance and cost, but also on how well th ...
A fuel cell is an electrochemical device that directly converts a fuel to electricity by means of reactions on the surfaces of ...
The leading automotive brands are being focused to produce electric vehicles because they believe they represent a harmony to the e ...
Fuel cells are typically classified according to type of electrolyte. While many varieties of fuel cells have been demonstrated in the laboratory, five major types are seeing development for commercial applications:
* Polymer electrolyte membrane (PEM) cells use a plastic (polymer) membrane that becomes electrically conducting when hydrated (saturated with water); they operate near 1001C.
* Alkaline fuel cells use a caustic electrolyte such as potassium hydroxide (KOH); they also operate near 1001C. (more…)
Transport applications tend to demand rapid start-up and instant dynamic response from fuel cell systems, so a high-temperature ...
Polymer Electrolyte Fuel Cells have high-power density, rapid startup, and low-temperature operation (around 80 to 120 C), and ...
Alkaline fuel cell, often known as the Bacon fuel cell following the British inventor’ name. It has become the most created fue ...
The fuel cell can trace its roots back to the 1800s when a Welsh-born, Oxford-educated barrister, Sir William Robert Grove, realize ...
A fuel cell is an electrochemical device that combines hydrogen with oxygen to generate electricity, heat and water to produce. ...
The energy that people use every day comes from many different sources. The resources are divided into two main groups: renewable energy and nonrenewable energy. Renewable energy sources are those that can be used again and again. Renewable energy resources have unlimited supply. (more…)
In Europe, modern renewable energy sources technologies were explored thoroughly for the first time after the oil embargo/ price cr ...
During the US Presidential Election 2008 Campaign, the renewable portfolio standard was one of the main agendas for Presidentia ...
The broad range of home solar energy systems are mostly known as Photovoltaic Systems (PV) or Thin Film Solar Technology. The s ...
The hydrogen can come from various sources including fossil fuels, wind, solar, biomass, nuclear, solar thermo-chemical reactio ...
Renewable energy sources cannot run out and causes so little damage to the environment that its use does not need to be restric ...
Energy is consumed by various segments of the economy, including households, commercial establishments, manufacturing enterprises, and electric power generators. Only a portion of total energy demand is sensitive to temperature changes. (more…)
Here, the sensitivity of energy demand to climate is measured two ways. The first method uses elasticities that provide simple summ ...
To determine the effects of past climate trends on global energy consumption, the econometric equations providing the degree day el ...
Establishing the impact of climate change on energy demand requires a measure of heating and cooling requirements. In the United St ...
Although the focus of many policy studies of climate change is on establishing the causal links between anthropogenic systems, emis ...
Climatologists generally agree that there is accumulating evidence that a warming trend has been occurring since the mid-1960s. The ...
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 ...
An important element for the entire infrastructure of hydrogen energy infrastructure is having hydrogen delivery system the safely and efficiently deliver hydrogen from productions sites to end stations. Hydrogen delivery methods are varying widely, most of them depend on the hydrogen production method and end use. Currently, hydrogen is transferred to a limited number of production plants by using pipeline or transported by road via cylinders, tube trailers. (more…)
The issues of hydrogen storage run through the hydrogen production, hydrogen transport, supply and demand for end use of hydrog ...
Hydrogen has many applications when it comes to fuel. It can be used both in internal combustion engines and hydrogen fuel cells. ...
With ethanol’s future uncertain, many commentators see the transportation debate evolving into a war between two other technologies ...
Scientists at the Carnegie Institution have found that using a high pressure can create a very unique material for storing hydr ...
All of today’s hydrogen conversion products, demonstration models, and prototypes possess some deficiencies; they cannot yet pr ...
Anyone who wants to save money on gas should be interested in the process of underground coal gasification, or UCG. It is an alternative way of obtaining clean fuels, one that has been explored more recently due to increasing oil prices. Considering that the process benefits everyone, it is surprising how few individuals have any idea what it is. Not only do its advantages affect everyone, but the ideas and technology behind UCG are also fascinating. For this reason, it is important to at least have an idea of what goes on underground during the coal gasification process. (more…)
Fossil fuels, had a broader impact in current society, still oil is the one that have far reaching effect. Oil, in all its forms is ...
Gasification is a thermo chemical process that has been exploited for more than a century for converting solid feedstocks to ga ...
Coal is an important energy source and energy consumption in United States as well as worldwide. It will remain so for many yea ...
The pilot plant for carbon dioxide capture and hydrogen production using combined cycle ELCOGAS Puertollano "will be the first in t ...
Federal Excise Taxes placed on specific energy sources tend to reduce energy demand for these energy sources in both the short ...