Certain materials, generally metal oxides, can sustain the unassisted photo-electrolysis of water into H2 and O2. The energy contained in the photons that are absorbed by these materials can in many cases be efficiently converted into energy stored into the chemical fuels produced by the photo-electrolysis system. However, these materials have optical absorption thresholds (band gaps) that are too large to permit effective absorption of the visible and infrared portions of the solar spectrum, thereby wasting a large fraction of the incident solar energy and yielding overall energy conversion efficiencies of o 1%. Modification of metal oxide materials has been claimed to be much more promising, with a modified TiO 2 photo-anode yielding 8% efficiency in the photo-assisted splitting of water into H2 and O2 . (more…)
Several molecular systems have been constructed that mimic various aspects of photosynthesis. Two of these utilize molecular system ...
The basic processes that occur in such a system are well understood. The semiconductor electrode efficiently absorbs light, produci ...
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. ...
All of today’s hydrogen conversion products, demonstration models, and prototypes possess some deficiencies; they cannot yet pr ...
The energy efficiencies of various fuel production pathways from well to pump. The efficiencies shown are defined as the energy in a given fuel (available at pumps in vehicle refueling stations) divided by total energy inputs during all Well-to-Pump activities, including the energy content of the fuel. One way to interpret the Well-to-Pump efficiencies in the figure is as the difference between 100% and the energy efficiencies, which roughly represent energy losses during Well-to-Pump stages for making a given fuel available at the pump. As stated in Section 3, Well-to-Pump activities include biomass feedstock production; feedstock transportation and storage; fuel production; and fuel transportation, storage, and distribution. (more…)
The combination of well-to-pump results and the energy use and emissions associated with vehicle operation (also called the pum ...
It shows Well-to-Wheels Greenhouse Gas emissions of the 23 vehicle/fuel systems. For each system, the bottom bar represents CO2 ...
Because different studies have different system boundaries and parametric assumptions, the studies described in Section 7 resulted ...
There are different types of vehicle propulsion systems and the transportation fuels that have been studied for their potential ...
At present, in the United States and worldwide, motor vehicles are fueled almost exclusively by petroleum based gasoline (or re ...
The most widespread and practical process for capture solar radiation as organic fuels is the growth of virgin biomass. Extremely large quantities of carbon are fixed each year in the form of terrestrial and aquatic biomass. (more…)
Another large source of renewable carbon supplies is waste biomass. It consists of a wide range of materials and includes munic ...
Another large source of renewable carbon supplies is waste biomass. It consists of a wide range of materials and includes munic ...
The future development of energy crops, to the level at which they would replace residues as the major bioenergy fuel source, will ...
The hydrogen can come from various sources including fossil fuels, wind, solar, biomass, nuclear, solar thermo-chemical reactio ...
The accumulation of carbon within a forest growth cycle can be considered in four stages. The initial establishment stage involves ...
Hydrogen has many applications when it comes to fuel. It can be used both in internal combustion engines and hydrogen fuel cells. Hydrogen engines are using the same principle the same way as gasoline fuels or hydrogen natural gas burned combustion, while the chemical energy of hydrogen used to generate electricity and heat transmission. Since the electrochemical reactions produced more efficient energy compare to the combustion energy, fuel cells are created more efficient fuel compare to internal combustion engines. In the long term it will benefit to the more efficient hydrogen conversion process. (more…)
All of today’s hydrogen conversion products, demonstration models, and prototypes possess some deficiencies; they cannot yet pr ...
Most production systems try to become first full-scale production begins as small toys and devices of concept. The Horizon hydr ...
A fuel cell is an electrochemical device that combines hydrogen with oxygen to generate electricity, heat and water to produce. ...
There are different types of vehicle propulsion systems and the transportation fuels that have been studied for their potential ...
The issues of hydrogen storage run through the hydrogen production, hydrogen transport, supply and demand for end use of hydrog ...
The hydrogen can come from various sources including fossil fuels, wind, solar, biomass, nuclear, solar thermo-chemical reactions, and solar photolysis. (more…)
Researchers at the Institute of Chemical Technology have developed a new catalyst that allows to obtain, from bioethanol, hydrogen ...
Hydrogen has many applications when it comes to fuel. It can be used both in internal combustion engines and hydrogen fuel cells. ...
The issues of hydrogen storage run through the hydrogen production, hydrogen transport, supply and demand for end use of hydrog ...
Most production systems try to become first full-scale production begins as small toys and devices of concept. The Horizon hydr ...
With ethanol’s future uncertain, many commentators see the transportation debate evolving into a war between two other technologies ...
Nuclear power plants have many different designs and shapes. Early technology restrictions in nuclear power plants make huge plants with the capability to produce the greatest amount of power possible. But with more recent technology, nuclear plants size are smaller , making them less costly and easier to build. But despite their many technical and engineering differences, nuclear reactors come in two basic types: pressurized water reactor systems and boiling water reactor systems. (more…)
Nuclear fission and fusion Research and Development continues to account for nearly half of the total spending by IEA countries, al ...
ITMA Foundation, a group of researchers formed by Javier Belzunce, José Manuel Artimez, Ana Moran and Ruben Coto, has developed the ...
Because a nuclear explosion in a nuclear power plant is impossible due to the low fuel enrichment, the worst conceivable accident i ...
In the United States, Department of Energy has determined that nuclear power accounts for about 21% of the total electricity ge ...
Electricity generation through nuclear power plant is an enormously complex technical feat. It takes the combined skills of geo ...