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Water As A Last Hope For Future Energy Needs

jamshaid56us

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Water As A Last Hope For Future Energy Needs
by Engr. Jamshaid Akhtar Minhas

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Water is the most essential element to life on Earth. Almost 71% of the Earth's surface is covered with water, approximately 55-80% of our body and 2/3 of universe is water, without water nothing can exist. The benefits of water goes far beyond the scope of just drinking water. I hope to broaden your perspective and open a window to a new view of water in our lives.

Water at its basic is a chemical substance with one oxygen and two hydrogen atoms bonded together by a covalent bond. Water appears in nature in all three states of matters. Water also exists in a liquid crystal state near hydrophilic surfaces. Clouds in the sky; seawater in the oceans; icebergs in the polar oceans; glaciers and rivers in the mountains; and the liquid in aquifers in the ground are all different forms of water. More than half of the world's water supply is contained in just nine countries: the United States, Canada, Colombia, Brazil, the Democratic Republic of Congo, Russia, India, China and Indonesia.

On 22 July 2011, a report described the discovery of a gigantic cloud of water vapour, containing "140 trillion times more water than all of Earth's oceans combined," around a quasar located 12 billion light years from Earth. According to the researchers, the discovery shows that water has been prevalent in the universe for nearly its entire existence.

Water is a major source of energy on Earth. Electricity obtained by driving a water turbine connected with a generator is known as hydroelectricity. It is a low-cost, non-polluting, renewable source of energy. Water is also used in many industrial processes and machines, such as the steam turbine and heat exchanger, in addition to its use as a chemical solvent.

On September 8, 1935, the first claim of water fuelled car by Charles H. Garrett was reported in The Dallas Morning News. The car generated hydrogen by electrolysis as can be seen by examining Garrett's patent, issued that same year. As several claims of driving cars on water were made since last century it’s time to have a serious consideration on this topic that “is it possible to run an engine with water? “.

Since water is the main cause of existence of life on Earth its constituents Oxygen and Hydrogen have the same importance. By mass, oxygen is the third-most abundant element in the universe, after hydrogen and helium. O2 compound is an important part of the atmosphere, and is necessary to sustain terrestrial life. Hydrogen gas is highly flammable and will burn in air at a very wide range of concentrations between 4% and 75% by volume.The enthalpy of combustion for hydrogen is −286 kJ/mol:

2 H2(g) + O2(g) → 2 H2O(l) + 572 kJ (286 kJ/mol)

Hydrogen gas forms explosive mixtures with air if it is 4–74% concentrated and with chlorine if it is 5–95% concentrated. The mixtures spontaneously explode by spark, heat or sunlight. Heat of Combustion for common fuels is as following Hydrogen 141.9 KJ/g, Gasoline 47KJ/g, Diesel 45 KJ/g and Ethanol 29.7 KJ/g. Hydrogen is also used to produce the most horrific bombs with its tremendous power. Hydrogen is a serious consideration for our fuel dilemma. Some people are worried that hydrogen might be too dangerous. It is true that hydrogen is a very explosive fuel, but so is natural gas and gasoline.

There are two ways to use hydrogen as fuel to drive our cars. First one is the use of fuel cells that convert chemical energy into electrical energy through a chemical reaction of oxygen and hydrogen to produce water. A typical fuel cell produces a voltage from 0.6 V to 0.7 V at full rated load. Voltage decreases as current increases, due to several factors: Activation loss, Ohmic loss and Mass transport loss. Fuel cells can be combined in series and parallel, where series yields higher voltage and parallel allows a higher current to be supplied.

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(A typical Fuel Cell)
The most popular way is to get hydrogen is electrolysis. The process by which we generate hydrogen and oxygen from water is called electrolysis. The word "lysis" means to dissolve or break apart, so the word "electrolysis" literally means to break something apart (in this case water) using electricity. Electrolysis is very simple - all you have to do is arrange for electricity to pass through some water between two electrodes placed in the water. It’s as simple as that! The principle of electrolysis was first formulated by Michael Faraday in 1820.

2 H2O(l) → 2 H2(g) + O2(g); E0 = -1.229 V

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First law of electrolysis:
In 1832, Michael Faraday reported that the quantity of elements separated by passing an electric current through a molten or dissolved salt is proportional to the quantity of electric charge passed through the circuit. This became the basis of the first law of electrolysis:
m = k .q


Second law of electrolysis:
Faraday discovered that when the same amount of electricity is passed through different electrolytes, the mass of substance liberated/deposited at the electrodes is directly proportional to their equivalent weights.

As this process consumes large amount of energy the efficiency of this process lies between 50% and 70%, while maximum theoretical efficiency of electrolysis is between 80% and 94%. The theoretical maximum considers the total amount of energy absorbed by both the hydrogen and oxygen. These values refer only to the efficiency of converting electrical energy into hydrogen's chemical energy. The energy lost in generating the electricity is not included. Dr Daniel G. Nocera a Professor of MIT is working on a project to improve efficiency of electrolysis with the help of artificial leafs invented at his lab. His research is mainly inspired by photosynthesis.

Thus due to the laws of physics energy cannot be created nor be destroyed but can only be converted from one form to another; also output cannot exceed input in its value because 100% efficiency is not possible in practical. So electrolysis is not feasible to produce hydrogen in such a large quantity for combustion to drive an automobile engine. So it’s impossible to run an automobile engine on 100% water fuel. Also there are no hydrogen filling stations in your towns so Hybrid Cars may not get vivid attention at domestic market for at least a decade.

Second way is to use hydrogen as a booster in combustion. Francois Isaac de Rivaz in 1806 designed the first internal combustion engine, which ran on a hydrogen/oxygen mixture. Paul Dieges patented in 1970 a modification to internal combustion engines which allowed a gasoline-powered engine to run on hydrogen. Recently, BMW tested a supercar, powered by a hydrogen ICE (internal combustion engine), which achieved 187 mph (301 km/h) in tests. At least two of these concepts have been manufactured.

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A hydrogen-boosted engine has much greater fuel combustion efficiency and quality. Invented by scientists at the Massachusetts Institute of Technology, and being perfected by auto industry supplier ArvinMeritor in cooperation with the German automotive engineering firm IAV, this system may provide a cost-effective alternative to fuel-cell technology and traditional gasoline- and diesel-combustion engines. It uses an add-on device called a reformer to extract a small amount of hydrogen from gasoline and inject it into the regular fuel-air mixture in the engine's combustion chamber, this amount of hydrogen can also be produced using electrolysis, it enables almost twice the volume of air to ignite with a given quantity of fuel than in a regular internal combustion engine. This promising new technology saves energy by reducing fuel consumption and also burns fuel more cleanly. A vehicle running on a mixture of hydrogen, gasoline and air can expect to achieve 20 to 30 percent better mileage than one with a traditional engine. The hydrogen-boosted engine runs cleanly, boosts fuel efficiency and does not require any special equipment for controlling harmful nitrogen oxide (NOx) emissions.

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(A Typical Diesel Engine)

The combustion of hydrogen with air can also produce oxides of nitrogen. Although it is only produced in small quantities, research has shown that the oxides of nitrogen are about 310 times more harmful for greenhouse gas than carbon dioxide, which is the only but most dangerous disadvantage of this technology.

H2 + O2 + N2 → H2O + N2 + NOx

A major cost and environmental advantage of the hydrogen-boosted lean system engine are low amounts of NOx emissions gasses, hence, complete elimination of the need for external NOx emissions control. Currently, NOx emissions control is a major cost problem for diesels which use expensive traps to meet emissions standards. Diesel particulate emissions must also be collected by a filter that must be periodically regenerated.

Hydrogen-boosted gasoline engines require neither NOx or particulate control filters and require only a low cost oxidation catalyst to control small amounts of exhaust (unburned hydrocarbons) formed mostly during engine start-up and early warm up. Additional cuts in emissions control requirements stem from the engine's ability to use only the clean hydrogen enriched charge during the cold start phase when 90% of emissions are generated in the emissions test.

It is only the matter of perspective that how far we will go in this field of science in future, it’s likely that we'll hear a lot more about the hydrogen-boosted engine in the future. But at present we can only wash our cars with water instead of fuelling them with it.









References:
1- Water - Wikipedia, the free encyclopedia
2- Electrolysis - Wikipedia, the free encyclopedia
3- Electrolysis
4- Electrolysis of Water and Fuel Cell Operation
5- Nocera Lab: Research Group of Daniel G. Nocera
6- HowStuffWorks "Photosynthesis"
7- What makes a hydrogen-boosted engine efficient? - Curiosity
8- What is a hydrogen-boosted gasoline engine? - Curiosity
9- HowStuffWorks "Hydrogen-Boosted Gasoline Engine Overview"
10- HowStuffWorks "How Car Engines Work"
11- HowStuffWorks "How Diesel Engines Work"
 
We should try to get hydrogen from outer space, since it is very abundant out there, maybe by routinely using space shuttles with huge containers, and rafiny it on earth, there will be no need for electrolysis, but which way will be more viable is a question to be studied.
 
Novel Nano-Structures to Realize Hydrogen's Energy Potential

Researchers from the Materials Energy Research Laboratory at the University of New South Wales in nanoscale (MERLin) at UNSW have synthesized nanoparticles of a commonly overlooked chemical compound called sodium borohydride and encased these inside nickel shells.

Their unique "core-shell" nanostructure has demonstrated remarkable hydrogen storage properties, including the release of energy at much lower temperatures than previously observed.

"No one has ever tried to synthesise these particles at the nanoscale because they thought it was too difficult, and couldn't be done. We're the first to do so, and demonstrate that energy in the form of hydrogen can be stored with sodium borohydride at practical temperatures and pressures," said Dr Kondo-Francois Aguey-Zinsou from the School of Chemical Engineering at UNSW.

Considered a major a fuel of the future, hydrogen could be used to power buildings, portable electronics and vehicles -- but this application hinges on practical storage technology.

Lightweight compounds known as borohydrides (including lithium and sodium compounds) are known to be effective storage materials but it was believed that once the energy was released it could not be reabsorbed -- a critical limitation. This perceived "irreversibility" means there has been little focus on sodium borohydride.

However, the result, published last week in the journal ACS Nano, demonstrates for the first time that reversibility is indeed possible using a borohydride material by itself and could herald significant advances in the design of novel hydrogen storage materials.

"By controlling the size and architecture of these structures we can tune theirproperties and make them reversible -- this means they can release and reabsorb hydrogen," said Aguey-Zinsou, lead author on the paper. "We now have a way to tap into all these borohydride materials, which are particularly exciting for application on vehicles because of their highhydrogen storage capacity."

The researchers observed remarkable improvements in the thermodynamic and kinetic properties of their material. This means the chemical reactions needed to absorb and release hydrogen occurred faster than previously studied materials, and at significantly reduced temperatures -- making possible application far more practical.

In its bulk form, sodium borohydride requires temperatures above 550 degrees Celsius just to release hydrogen. Even on the nano-scale the improvements were minimal. However, with their core-shell nanostructure, the researchers saw initial energy release happening at just 50 °C, and significant release at 350 °C.

"The new materials that could be generated by this exciting strategy could provide practical solutions to meet many of the energy targets set by the US Department of Energy," said Aguey-Zinsou. "The key thing here is that we've opened the doorway."


Fars News Agency :: Novel Nano-Structures to Realize Hydrogen's Energy Potential
 
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