veteranstoday--2020-09-05--VT Nuclear Education: Fuel Cell Technology

The first references to hydrogen fuel cells appeared in 1838 .
In a letter dated October 1838 but published in the December 1838 edition of The London and Edinburgh Philosophical Magazine and Journal of Science , Welsh physicist and barrister William Grove wrote about the development of his first crude fuel cells .
He used a combination of sheet iron , copper and porcelain plates , and a solution of sulphate of copper and dilute acid .
In a letter to the same publication written in December 1838 but published in June 1839 , German physicist Christian Friedrich Schönbein discussed @ @ @ @ @ @ @ had invented .
His letter discussed current generated from hydrogen and oxygen dissolved in water .
Grove later sketched his design , in 1842 , in the same journal .
The fuel cell he made used similar materials to today ’ s phosphoric-acid fuel cell .
In 1939 , British engineer Francis Thomas Bacon successfully developed a 5 kW stationary fuel cell .
In 1955 , W. Thomas Grubb , a chemist working for the General Electric Company , further modified the original fuel cell design by using a sulphonated polystyrene ion-exchange membrane @ @ @ @ @ @ @ another GE chemist , Leonard Niedrach , devised a way of depositing platinum onto the membrane , which served as catalyst for the necessary hydrogen oxidation and oxygen reduction reactions .
This became known as the “ Grubb-Niedrach fuel cell ” .
GE went on to develop this technology with NASA and McDonnell Aircraft , leading to its use during Project Gemini .
This was the first commercial use of a fuel cell .
In 1959 , a team led by Harry Ihrig built a 15 kW fuel cell tractor for Allis-Chalmers , @ @ @ @ @ @ @ state fairs .
This system used potassium hydroxide as the electrolyte and compressed hydrogen and oxygen as the reactants .
Later in 1959 , Bacon and his colleagues demonstrated a practical five-kilowatt unit capable of powering a welding machine .
In the 1960s , Pratt and Whitney licensed Bacon ’ s U.S. patents for use in the U.S. space program to supply electricity and drinking water ( hydrogen and oxygen being readily available from the spacecraft tanks ) .
In 1991 , the first hydrogen fuel cell automobile was developed by Roger Billings @ @ @ @ @ @ @ to manufacture and commercialize a large , stationary fuel cell system for use as a co-generation power plant in hospitals , universities and large office buildings .
UTC Power continues to be the sole supplier of fuel cells to NASA for use in space vehicles , having supplied fuel cells for the Apollo missions , and the Space Shuttle program , and is developing fuel cells for cell phone towers and other applications .
Fuel cells come in many varieties ; however , they all work in the same general manner .
They @ @ @ @ @ @ @ : the anode , the electrolyte , and the cathode .
Two chemical reactions occur at the interfaces of the three different segments .
The net result of the two reactions is that fuel is consumed , water or carbon dioxide is created , and an electric current is created , which can be used to power electrical devices , normally referred to as the load .
At the anode a catalyst oxidizes the fuel , usually hydrogen , turning the fuel into a positively charged ion and a negatively charged electron .
@ @ @ @ @ @ @ so ions can pass through it , but the electrons can not .
The freed electrons travel through a wire creating the electric current .
The ions travel through the electrolyte to the cathode .
Once reaching the cathode , the ions are reunited with the electrons and the two react with a third chemical , usually oxygen , to create water or carbon dioxide .
This is a catalytic reaction with hydrogen and oxygen .
In Cold Fusion cells the same process is used to create excess heat from the catalytic reaction @ @ @ @ @ @ @ use , only the excess thermal heat is extracted from the cell for use .
The most important design features in a fuel cell are : • The electrolyte substance .
The electrolyte substance usually defines the type of fuel cell .
• The fuel that is used .
The most common fuel is hydrogen .
• The anode catalyst breaks down the fuel into electrons and ions .
The anode catalyst is usually made up of very fine platinum powder .
• The cathode catalyst turns the ions into the waste chemicals @ @ @ @ @ @ @ cathode catalyst is often made up of nickel but it can also be a nano material-based catalyst .
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 : • Ohmic loss ( voltage drop due to resistance of the cell components and interconnections ) • Mass transport loss ( depletion of reactants at catalyst sites under high loads , causing rapid loss of voltage ) .
To deliver the desired amount of energy , @ @ @ @ @ @ @ series to yield higher voltage , and in parallel to allow a higher current to be supplied .
Such a design is called a fuel cell stack .
The cell surface area can also be increased , to allow higher current from each cell .
Within the stack , reactant gases must be distributed uniformly over each of the cells to maximize the power output .
In the archetypical hydrogen–oxide proton exchange membrane fuel cell design , a proton-conducting polymer membrane ( the electrolyte ) separates the anode and cathode sides .
This @ @ @ @ @ @ @ fuel cell ” ( SPEFC ) in the early 1970s , before the proton exchange mechanism was well-understood .
( Notice that the synonyms “ polymer electrolyte membrane ” and “ proton exchange mechanism ” result in the same acronym . )
On the anode side , hydrogen diffuses to the anode catalyst where it later dissociates into protons and electrons .
These protons often react with oxidants causing them to become what are commonly referred to as multi-facilitated proton membranes .
The protons are conducted through the membrane to the cathode , @ @ @ @ @ @ @ in an external circuit ( supplying power ) because the membrane is electrically insulating .
On the cathode catalyst , oxygen molecules react with the electrons ( which have traveled through the external circuit ) and protons to form water .
In addition to this pure hydrogen type , there are hydrocarbon fuels for fuel cells , including diesel , methanol and chemical hydrides .
The waste products with these types of fuel are carbon dioxide and water , when hydrogen is used the CO2 is released when methane from natural gas is @ @ @ @ @ @ @ steam methane reforming to produce the hydrogen , this can take place in a different location to the fuel cell potentially allowing the hydrogen fuel cell to be used indoors for example in fork lifts .
The different components of a PEMFC are ; The materials used for different parts of the fuel cells differ by type .
The bipolar plates may be made of different types of materials , such as , metal , coated metal , graphite , flexible graphite , C–C composite , carbon–polymer composites etc .
The membrane electrode @ @ @ @ @ @ @ the heart of the PEMFC and is usually made of a proton exchange membrane sandwiched between two catalyst-coated carbon papers .
Platinum and/or similar type of noble metals are usually used as the catalyst for PEMFC .
The electrolyte could be a polymer membrane .
• Costs .
In 2013 , the Department of Energy estimated that 80-kW automotive fuel cell system costs of US $ 67 per kilowatt could be achieved , assuming volume production of 100,000 automotive units per year and US $ 55 per kilowatt could be achieved , assuming @ @ @ @ @ @ @ .
Many companies are working on techniques to reduce cost in a variety of ways including reducing the amount of platinum needed in each individual cell .
30 % reduction ( 1 mg/cm² to 0.7 mg/cm² ) in platinum usage without reduction in performance .
A 2011 published study documented the first metal-free electro catalyst using relatively inexpensive doped carbon nanotubes , which are less than 1 % the cost of platinum and are of equal or superior performance .
• Water and air management ( in PEMFCs ) .
In this type @ @ @ @ @ @ @ be hydrated , requiring water to be evaporated at precisely the same rate that it is produced .
If water is evaporated too quickly , the membrane dries , resistance across it increases , and eventually it will crack , creating a gas “ short circuit ” where hydrogen and oxygen combine directly , generating heat that will damage the fuel cell .
If the water is evaporated too slowly , the electrodes will flood , preventing the reactants from reaching the catalyst and stopping the reaction .
Methods to manage water in @ @ @ @ @ @ @ focusing on flow control .
Just as in a combustion engine , a steady ratio between the reactant and oxygen is necessary to keep the fuel cell operating efficiently .
• Temperature management .
The same temperature must be maintained throughout the cell in order to prevent destruction of the cell through thermal loading .
This is particularly challenging as the 2H + O - > 2H O reaction is highly exothermic , so a large quantity of heat is generated within the fuel cell .
• Durability , service life , and @ @ @ @ @ @ @ .
Stationary fuel cell applications typically require more than 40,000 hours of reliable operation at a temperature of −35 °C to 40 °C ( −31 °F to 104 °F ) , while automotive fuel cells require a 5,000-hour lifespan ( the equivalent of 240,000 km ( 150,000 mi ) ) under extreme temperatures .
Current service life is 7,300 hours under cycling conditions .
Automotive engines must also be able to start reliably at −30 °C ( −22 °F ) and have a high power-to-volume ratio ( typically 2.5 kW per liter ) @ @ @ @ @ @ @ ) were first designed and introduced in 1961 by G. V. Elmore and H. A. Tanner .
In these cells phosphoric acid is used as a non-conductive electrolyte to pass positive hydrogen ions from the anode to the cathode .
These cells commonly work in temperatures of 150 to 200 degrees Celsius .
This high temperature will cause heat and energy loss if the heat is not removed and used properly .
This heat can be used to produce steam for air conditioning systems or any other thermal energy consuming system .
The @ @ @ @ @ @ @ from 40 to about 80 % .
Phosphoric acid , the electrolyte used in PAFCs , is a non-conductive liquid acid which forces electrons to travel from anode to cathode through an external electrical circuit .
Since the hydrogen ion production rate on the anode is small , platinum is used as catalyst to increase this ionization rate .
A key disadvantage of these cells is the use of an acidic electrolyte .
This increases the corrosion or oxidation of components exposed to phosphoric acid .
Solid oxide fuel cells ( SOFCs ) @ @ @ @ @ @ @ a ceramic material called yttria-stabilized zirconia ( YSZ ) , as the electrolyte .
Because SOFCs are made entirely of solid materials , they are not limited to the flat plane configuration of other types of fuel cells and are often designed as rolled tubes .
They require high operating temperatures ( 800–1000 °C ) and can be run on a variety of fuels including natural gas .
SOFCs are unique in that negatively charged oxygen ions travel from the cathode ( positive side of the fuel cell ) to the anode ( @ @ @ @ @ @ @ instead of positively charged hydrogen ions travelling from the anode to the cathode , as is the case in all other types of fuel cells .
Oxygen gas is fed through the cathode , where it absorbs electrons to create oxygen ions .
The oxygen ions then travel through the electrolyte to react with hydrogen gas at the anode .
The reaction at the anode produces electricity and water as by-products .
Carbon dioxide may also be a by-product depending on the fuel , but the carbon emissions from an SOFC system are @ @ @ @ @ @ @ combustion plant .
The chemical reactions for the SOFC system can be expressed as follows : SOFC systems can run on fuels other than pure hydrogen gas .
However , since hydrogen is necessary for the reactions listed above , the fuel selected must contain hydrogen atoms .
For the fuel cell to operate , the fuel must be converted into pure hydrogen gas .
SOFCs are capable of internally reforming light hydrocarbons such as methane ( natural gas ) , propane and butane .
These fuel cells are at an early stage @ @ @ @ @ @ @ systems due to their high operating temperatures .
One such challenge is the potential for carbon dust to build up on the anode , which slows down the internal reforming process .
Research to address this “ carbon coking ” issue at the University of Pennsylvania has shown that the use of copper-based cermet ( heat-resistant materials made of ceramic and metal ) can reduce coking and the loss of performance .
Another disadvantage of SOFC systems is slow start-up time , making SOFCs less useful for mobile applications .
Despite these disadvantages @ @ @ @ @ @ @ advantage by removing the need for a precious metal catalyst like platinum , thereby reducing cost .
Additionally , waste heat from SOFC systems may be captured and reused , increasing the theoretical overall efficiency to as high as 80 % –85 % .
The high operating temperature is largely due to the physical properties of the YSZ electrolyte .
As temperature decreases , so does the ionic conductivity of YSZ .
Therefore , to obtain optimum performance of the fuel cell , a high operating temperature is required .
According to their @ @ @ @ @ @ @ SOFC fuel cell manufacturer , has developed a method of reducing the operating temperature of their SOFC system to 500–600 degrees Celsius .
They replaced the commonly used YSZ electrolyte with a CGO ( cerium gadolinium oxide ) electrolyte .
The lower operating temperature allows them to use stainless steel instead of ceramic as the cell substrate , which reduces cost and start-up time of the system .
Molten carbonate fuel cells ( MCFCs ) require a high operating temperature , 650 °C ( 1,200 °F ) , similar to SOFCs .
MCFCs @ @ @ @ @ @ @ electrolyte , and this salt liquefies at high temperatures , allowing for the movement of charge within the cell – in this case , negative carbonate ions .
Like SOFCs , MCFCs are capable of converting fossil fuel to a hydrogen-rich gas in the anode , eliminating the need to produce hydrogen externally .
The reforming process creates CO 2 emissions .
MCFC-compatible fuels include natural gas , biogas and gas produced from coal .
The hydrogen in the gas reacts with carbonate ions from the electrolyte to produce water , carbon dioxide @ @ @ @ @ @ @ chemicals .
The electrons travel through an external circuit creating electricity and return to the cathode .
There , oxygen from the air and carbon dioxide recycled from the anode react with the electrons to form carbonate ions that replenish the electrolyte , completing the circuit .
The chemical reactions for an MCFC system can be expressed as follows : As with SOFCs , MCFC disadvantages include slow start-up times because of their high operating temperature .
This makes MCFC systems not suitable for mobile applications , and this technology will most likely @ @ @ @ @ @ @ .
The main challenge of MCFC technology is the cells ’ short life span .
The high-temperature and carbonate electrolyte lead to corrosion of the anode and cathode .
These factors accelerate the degradation of MCFC components , decreasing the durability and cell life .
Researchers are addressing this problem by exploring corrosion-resistant materials for components as well as fuel cell designs that may increase cell life without decreasing performance .
MCFCs hold several advantages over other fuel cell technologies , including their resistance to impurities .
They are not prone to “ @ @ @ @ @ @ @ carbon build-up on the anode that results in reduced performance by slowing down the internal fuel reforming process .
Therefore , carbon-rich fuels like gases made from coal are compatible with the system .
The Department of Energy claims that coal , itself , might even be a fuel option in the future , assuming the system can be made resistant to impurities such as sulfur and particulates that result from converting coal into hydrogen .
MCFCs also have relatively high efficiencies .
They can reach a fuel-to-electricity efficiency of 50 % , @ @ @ @ @ @ @ of a phosphoric acid fuel cell plant .
Comparison of fuel cell types • Anode : The electrode at which oxidation ( a loss of electrons ) takes place .
For fuel cells and other galvanic cells , the anode is the negative terminal ; for electrolytic cells ( where electrolysis occurs ) , the anode is the positive terminal .
• Aqueous solution : a : of , relating to , or resembling water b : made from , with , or by water .
• Catalyst : A chemical substance that @ @ @ @ @ @ @ being consumed ; after the reaction , it can potentially be recovered from the reaction mixture and is chemically unchanged .
The catalyst lowers the activation energy required , allowing the reaction to proceed more quickly or at a lower temperature .
In a fuel cell , the catalyst facilitates the reaction of oxygen and hydrogen .
It is usually made of platinum powder very thinly coated onto carbon paper or cloth .
The catalyst is rough and porous so the maximum surface area of the platinum can be exposed to the hydrogen @ @ @ @ @ @ @ the catalyst faces the membrane in the fuel cell .
• Cathode : The electrode at which reduction ( a gain of electrons ) occurs .
For fuel cells and other galvanic cells , the cathode is the positive terminal ; for electrolytic cells ( where electrolysis occurs ) , the cathode is the negative terminal .
• Electrolyte : A substance that conducts charged ions from one electrode to the other in a fuel cell , battery , or electrolyzer .
• Fuel Cell Stack : Individual fuel cells connected in a @ @ @ @ @ @ @ increase voltage .
• Matrix : something within or from which something else originates , develops , or takes form .
• Membrane : The separating layer in a fuel cell that acts as electrolyte ( an ion-exchanger ) as well as a barrier film separating the gases in the anode and cathode compartments of the fuel cell .
• Molten Carbonate Fuel Cell ( MCFC ) : A type of fuel cell that contains a molten carbonate electrolyte .
Carbonate ions ( CO 2− ) are transported from the cathode to the @ @ @ @ @ @ @ 650 °C .
[ 46 ] • Phosphoric acid fuel cell ( PAFC ) : A type of fuel cell in which the electrolyte consists of concentrated phosphoric acid ( H PO ) .
Protons ( H+ ) are transported from the anode to the cathode .
The operating temperature range is generally 160–220 °C .
• Polymer Electrolyte Membrane ( PEM ) : A fuel cell incorporating a solid polymer membrane used as its electrolyte .
Protons ( H+ ) are transported from the anode to the cathode .
The operating temperature @ @ @ @ @ @ @ Solid Oxide Fuel Cell ( SOFC ) : A type of fuel cell in which the electrolyte is a solid , nonporous metal oxide , typically zirconium oxide ( ZrO ) treated with Y O , and O2− is transported from the cathode to the anode .
Any CO in the reformate gas is oxidized to CO at the anode .
Temperatures of operation are typically 800–1,000 °C .
• Solution : a : an act or the process by which a solid , liquid , or gaseous substance is homogeneously mixed with @ @ @ @ @ @ @ solid , b : a homogeneous mixture formed by this process ; especially : a single-phase liquid system , c : the condition of being dissolved The energy efficiency of a system or device that converts energy is measured by the ratio of the amount of useful energy put out by the system ( “ output energy ” ) to the total amount of energy that is put in ( “ input energy ” ) or by useful output energy as a percentage of the total input energy .
In the case of @ @ @ @ @ @ @ measured in electrical energy produced by the system .
Input energy is the energy stored in the fuel .
According to the U.S. Department of Energy , fuel cells are generally between 40–60 % energy efficient .
This is higher than some other systems for energy generation .
For example , the typical internal combustion engine of a car is about 25 % energy efficient .
In combined heat and power ( CHP ) systems , the heat produced by the fuel cell is captured and put to use , increasing the efficiency @ @ @ @ @ @ @ % .
The theoretical maximum efficiency of any type of power generation system is never reached in practice , and it does not consider other steps in power generation , such as production , transportation and storage of fuel and conversion of the electricity into mechanical power .
However , this calculation allows the comparison of different types of power generation .
The maximum theoretical energy efficiency of a fuel cell is 83 % , operating at low power density and using pure hydrogen and oxygen as reactants ( assuming no heat recapture @ @ @ @ @ @ @ , this compares with a maximum theoretical efficiency of 58 % for internal combustion engines .
While these efficiencies are not approached in most real world applications , high-temperature fuel cells ( solid oxide fuel cells or molten carbonate fuel cells ) can theoretically be combined with gas turbines to allow stationary fuel cells to come closer to the theoretical limit .
A gas turbine would capture heat from the fuel cell and turn it into mechanical energy to increase the fuel cell ’ s operational efficiency .
This solution has been predicted @ @ @ @ @ @ @ as 70 % .
The tank-to-wheel efficiency of a fuel-cell vehicle is greater than 45 % at low loads and shows average values of about 36 % when a driving cycle like the NEDC ( New European Driving Cycle ) is used as test procedure .
The comparable NEDC value for a Diesel vehicle is 22 % .
In 2008 Honda released a demonstration fuel cell electric vehicle ( the Honda FCX Clarity ) with fuel stack claiming a 60 % tank-to-wheel efficiency .
It is also important to take losses due to @ @ @ @ @ @ @ into account .
Fuel cell vehicles running on compressed hydrogen may have a power-plant-to-wheel efficiency of 22 % if the hydrogen is stored as high-pressure gas , and 17 % if it is stored as liquid hydrogen .
Fuel cells can not store energy like a battery , except as hydrogen , but in some applications , such as stand-alone power plants based on discontinuous sources such as solar or wind power , they are combined with electrolyzers and storage systems to form an energy storage system .
Most hydrogen , however , @ @ @ @ @ @ @ and so most hydrogen production emits carbon dioxide .
The overall efficiency ( electricity to hydrogen and back to electricity ) of such plants ( known as round-trip efficiency ) , using pure hydrogen and pure oxygen can be “ from 35 up to 50 percent ” , depending on gas density and other conditions .
While a much cheaper lead–acid battery might return about 90 % , the electrolyzer/fuel cell system can store indefinite quantities of hydrogen , and is therefore better suited for long-term storage .
Solid-oxide fuel cells produce exothermic @ @ @ @ @ @ @ and hydrogen .
The ceramic can run as hot as 800 degrees Celsius .
This heat can be captured and used to heat water in a micro combined heat and power ( m-CHP ) application .
When the heat is captured , total efficiency can reach 80–90 % at the unit , but does not consider production and distribution losses .
CHP units are being developed today for the European home market .
Professor Jeremy P. Meyers , in the Electrochemical Society journal Interface in 2008 , wrote , “ While fuel cells @ @ @ @ @ @ @ they are not as efficient as batteries , due primarily to the inefficiency of the oxygen reduction reaction ( and … the oxygen evolution reaction , should the hydrogen be formed by electrolysis of water ) … .
[ T ] hey make the most sense for operation disconnected from the grid , or when fuel can be provided continuously .
For applications that require frequent and relatively rapid start-ups … where zero emissions are a requirement , as in enclosed spaces such as warehouses , and where hydrogen is considered an acceptable @ @ @ @ @ @ @ ] is becoming an increasingly attractive choice [ if exchanging batteries is inconvenient ] ” .
In 2013 military organizations are evaluating fuel cells to significantly reduce the battery weight carried by soldiers .
Stationary fuel cells are used for commercial , industrial and residential primary and backup power generation .
Fuel cells are very useful as power sources in remote locations , such as spacecraft , remote weather stations , large parks , communications centers , rural locations including research stations , and in certain military applications .
A fuel cell system @ @ @ @ @ @ @ lightweight , and have no major moving parts .
Because fuel cells have no moving parts and do not involve combustion , in ideal conditions they can achieve up to 99.9999 % reliability .
This equates to less than one minute of downtime in a six-year period .
Since fuel cell electrolyzer systems do not store fuel in themselves , but rather rely on external storage units , they can be successfully applied in large-scale energy storage , rural areas being one example.There are many different types of stationary fuel cells so efficiencies @ @ @ @ @ @ @ % and 60 % energy efficient .
However , when the fuel cell ’ s waste heat is used to heat a building in a co-generation system this efficiency can increase to 85 % .This is significantly more efficient than traditional coal power plants , which are only about one third energy efficient .
Assuming production at scale , fuel cells could save 20–40 % on energy costs when used in co-generation systems .
They are also much cleaner than traditional power generation ; a fuel cell power plant using natural gas as @ @ @ @ @ @ @ one ounce of pollution ( other than CO 2 ) for every 1,000 kW·h produced , compared to 25 pounds of pollutants generated by conventional combustion systems .
Fuel Cells also produce 97 % less nitrogen oxide emissions than conventional coal-fired power plants .
Although there are currently no fuel cell vehicles available for commercial sale , over 20 fuel cell electric vehicle ( FCEV ) prototypes and demonstration cars have been released since 2009 .
Demonstration models include the Honda FCX Clarity , Toyota FCHV-adv , and Mercedes-Benz F-Cell .
As of @ @ @ @ @ @ @ than 4,800,000 km ( 3,000,000 mi ) , with more than 27,000 refuelings .
Demonstration fuel cell vehicles have been produced with “ a driving range of more than 400 km ( 250 mi ) between refueling ” .
They can be refueled in less than 5 minutes .
The U.S. Department of Energy ’ s Fuel Cell Technology Program claims that , as of 2011 , fuel cells achieved 53–59 % efficiency at one-quarter power and 42–53 % vehicle efficiency at full power , and a durability of over 120,000 km ( @ @ @ @ @ @ @ % degradation .
In a Well-to-Wheels simulation analysis , that “ did not address the economics and market constraints ” , General Motors and its partners estimated that per mile traveled , a fuel cell electric vehicle running on compressed gaseous hydrogen produced from natural gas could use about 40 % less energy and emit 45 % less greenhouse gasses than an internal combustion vehicle .
A lead engineer from the Department of Energy whose team is testing fuel cell cars said in 2011 that the potential appeal is that “ these are @ @ @ @ @ @ @ or refueling rate so they are a direct replacement for any vehicle .
For instance , if you drive a full sized SUV and pull a boat up into the mountains , you can do that with this technology and you can ’ t with current battery-only vehicles , which are more geared toward city driving.
” Some experts believe , however , that fuel cell cars will never become economically competitive with other technologies or that it will take decades for them to become profitable .
“ Only about 25 % of @ @ @ @ @ @ @ , or sun is converted to practical use.
” The study further noted that “ Electricity obtained from hydrogen fuel cells appears to be four times as expensive as electricity drawn from the electrical transmission grid .
… Because of the high energy losses [ hydrogen ] can not compete with electricity.
” Furthermore , the study found : “ Natural gas reforming is not a sustainable solution ” .
“ The large amount of energy required to isolate hydrogen from natural compounds ( water , natural gas , biomass ) , package @ @ @ @ @ @ @ , transfer the energy carrier to the user , plus the energy lost when it is converted to useful electricity with fuel cells , leaves around 25 % for practical use.
” Boeing researchers and industry partners throughout Europe conducted experimental flight tests in February 2008 of a manned airplane powered only by a fuel cell and lightweight batteries .
The fuel cell demonstrator airplane , as it was called , used a proton exchange membrane ( PEM ) fuel cell/lithium-ion battery hybrid system to power an electric motor , which was coupled @ @ @ @ @ @ @ , the world ’ s first propeller-driven airplane to be powered entirely by a fuel cell was flown .
The fuel cell was a unique FlatStackTM stack design , which allowed the fuel cell to be integrated with the aerodynamic surfaces of the plane .
There have been several fuel-cell-powered unmanned aerial vehicles ( UAV ) .
A Horizon fuel cell UAV set the record distance flown for a small UAV in 2007 .
The military is especially interested in this application because of the low noise , low thermal signature and ability @ @ @ @ @ @ @ the Naval Research Laboratory ’ s ( NRL ’ s ) Ion Tiger utilized a hydrogen-powered fuel cell and flew for 23 hours and 17 minutes .
The world ’ s first fuel-cell boat HYDRA used an AFC system with 6.5 kW net output .
Iceland has committed to converting its vast fishing fleet to use fuel cells to provide auxiliary power by 2015 and , eventually , to provide primary power in its boats .
Amsterdam recently introduced its first fuel-cell-powered boat that ferries people around the city ’ s famous and @ @ @ @ @ @ @ of the German and Italian navies use fuel cells to remain submerged for weeks without the need to surface .
The U212A is a non-nuclear submarine developed by German naval shipyard Howaldtswerke Deutsche Werft .
The system consists of nine PEM fuel cells , providing between 30 kW and 50 kW each .
The ship is silent giving it an advantage in the detection of other submarines .
A Recent naval paper has theorized about the the possibility of a Nuclear-Fuel Cell Hybrid whereby the fuel cell is used when silent operations are @ @ @ @ @ @ @ reactor ( and water ) .
Such a system could potentially give a submarine weeks of stealth capability at a time with the endurance of a Nuclear reactor .
It is not known if any such submarines have been built .

Sketch of William Grove’s 1839 fuel cell
The first references to hydrogen fuel cells appeared in 1838. In a letter dated October 1838 but published in the December 1838 edition of The London and Edinburgh Philosophical Magazine and Journal of Science, Welsh physicist and barrister William Grove wrote about the development of his first crude fuel cells. He used a combination of sheet iron, copper and porcelain plates, and a solution of sulphate of copper and dilute acid.
In a letter to the same publication written in December 1838 but published in June 1839, German physicist Christian Friedrich Schönbein discussed the first crude fuel cell that he had invented. His letter discussed current generated from hydrogen and oxygen dissolved in water. Grove later sketched his design, in 1842, in the same journal. The fuel cell he made used similar materials to today’s phosphoric-acid fuel cell.
In 1939, British engineer Francis Thomas Bacon successfully developed a 5 kW stationary fuel cell. In 1955, W. Thomas Grubb, a chemist working for the General Electric Company, further modified the original fuel cell design by using a sulphonated polystyrene ion-exchange membrane as the electrolyte. Three years later another GE chemist, Leonard Niedrach, devised a way of depositing platinum onto the membrane, which served as catalyst for the necessary hydrogen oxidation and oxygen reduction reactions.
This became known as the “Grubb-Niedrach fuel cell”. GE went on to develop this technology with NASA and McDonnell Aircraft, leading to its use during Project Gemini. This was the first commercial use of a fuel cell. In 1959, a team led by Harry Ihrig built a 15 kW fuel cell tractor for Allis-Chalmers, which was demonstrated across the U.S. at state fairs. This system used potassium hydroxide as the electrolyte and compressed hydrogen and oxygen as the reactants.
Later in 1959, Bacon and his colleagues demonstrated a practical five-kilowatt unit capable of powering a welding machine. In the 1960s, Pratt and Whitney licensed Bacon’s U.S. patents for use in the U.S. space program to supply electricity and drinking water (hydrogen and oxygen being readily available from the spacecraft tanks). In 1991, the first hydrogen fuel cell automobile was developed by Roger Billings.
UTC Power was the first company to manufacture and commercialize a large, stationary fuel cell system for use as a co-generation power plant in hospitals, universities and large office buildings. UTC Power continues to be the sole supplier of fuel cells to NASA for use in space vehicles, having supplied fuel cells for the Apollo missions, and the Space Shuttle program, and is developing fuel cells for cell phone towers and other applications.
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Types of fuel cells; design
Fuel cells come in many varieties; however, they all work in the same general manner. They are made up of three adjacent segments: the anode, the electrolyte, and the cathode. Two chemical reactions occur at the interfaces of the three different segments. The net result of the two reactions is that fuel is consumed, water or carbon dioxide is created, and an electric current is created, which can be used to power electrical devices, normally referred to as the load.
At the anode a catalyst oxidizes the fuel, usually hydrogen, turning the fuel into a positively charged ion and a negatively charged electron. The electrolyte is a substance specifically designed so ions can pass through it, but the electrons cannot. The freed electrons travel through a wire creating the electric current. The ions travel through the electrolyte to the cathode.
Once reaching the cathode, the ions are reunited with the electrons and the two react with a third chemical, usually oxygen, to create water or carbon dioxide. This is a catalytic reaction with hydrogen and oxygen. In Cold Fusion cells the same process is used to create excess heat from the catalytic reaction but no external electricity is produced for use, only the excess thermal heat is extracted from the cell for use.
The most important design features in a fuel cell are:
The electrolyte substance. The electrolyte substance usually defines the type of fuel cell.
of fuel cell. The fuel that is used. The most common fuel is hydrogen.
The anode catalyst breaks down the fuel into electrons and ions. The anode catalyst is usually made up of very fine platinum powder.
The cathode catalyst turns the ions into the waste chemicals like water or carbon dioxide. The cathode catalyst is often made up of nickel but it can also be a nano material-based catalyst.
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 (voltage drop due to resistance of the cell components and interconnections)
Mass transport loss (depletion of reactants at catalyst sites under high loads, causing rapid loss of voltage).
To deliver the desired amount of energy, the fuel cells can be combined in series to yield higher voltage, and in parallel to allow a higher current to be supplied. Such a design is called a fuel cell stack. The cell surface area can also be increased, to allow higher current from each cell. Within the stack, reactant gases must be distributed uniformly over each of the cells to maximize the power output.
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Proton exchange membrane fuel cells (PEMFCs)
In the archetypical hydrogen–oxide proton exchange membrane fuel cell design, a proton-conducting polymer membrane (the electrolyte) separates the anode and cathode sides. This was called a “solid polymer electrolyte fuel cell” (SPEFC) in the early 1970s, before the proton exchange mechanism was well-understood. (Notice that the synonyms “polymer electrolyte membrane” and “proton exchange mechanism” result in the same acronym.)
On the anode side, hydrogen diffuses to the anode catalyst where it later dissociates into protons and electrons. These protons often react with oxidants causing them to become what are commonly referred to as multi-facilitated proton membranes. The protons are conducted through the membrane to the cathode, but the electrons are forced to travel in an external circuit (supplying power) because the membrane is electrically insulating. On the cathode catalyst, oxygen molecules react with the electrons (which have traveled through the external circuit) and protons to form water.
In addition to this pure hydrogen type, there are hydrocarbon fuels for fuel cells, including diesel, methanol and chemical hydrides. The waste products with these types of fuel are carbon dioxide and water, when hydrogen is used the CO2 is released when methane from natural gas is combined with steam in a process called steam methane reforming to produce the hydrogen, this can take place in a different location to the fuel cell potentially allowing the hydrogen fuel cell to be used indoors for example in fork lifts.
The different components of a PEMFC are;
bipolar plates electrodes catalyst membrane
The materials used for different parts of the fuel cells differ by type. The bipolar plates may be made of different types of materials, such as, metal, coated metal, graphite, flexible graphite, C–C composite, carbon–polymer composites etc. The membrane electrode assembly (MEA) is referred as the heart of the PEMFC and is usually made of a proton exchange membrane sandwiched between two catalyst-coated carbon papers. Platinum and/or similar type of noble metals are usually used as the catalyst for PEMFC. The electrolyte could be a polymer membrane.
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Proton exchange membrane fuel cell design issues
Costs. In 2013, the Department of Energy estimated that 80-kW automotive fuel cell system costs of US$67 per kilowatt could be achieved, assuming volume production of 100,000 automotive units per year and US$55 per kilowatt could be achieved, assuming volume production of 500,000 units per year. Many companies are working on techniques to reduce cost in a variety of ways including reducing the amount of platinum needed in each individual cell. 30% reduction (1 mg/cm² to 0.7 mg/cm²) in platinum usage without reduction in performance. A 2011 published study documented the first metal-free electro catalyst using relatively inexpensive doped carbon nanotubes, which are less than 1% the cost of platinum and are of equal or superior performance.
Many companies are working on techniques to reduce cost in a variety of ways including reducing the amount of platinum needed in each individual cell. 30% reduction (1 mg/cm² to 0.7 mg/cm²) in platinum usage without reduction in performance. A 2011 published study documented the first metal-free electro catalyst using relatively inexpensive doped carbon nanotubes, which are less than 1% the cost of platinum and are of equal or superior performance. Water and air management (in PEMFCs). In this type of fuel cell, the membrane must be hydrated, requiring water to be evaporated at precisely the same rate that it is produced. If water is evaporated too quickly, the membrane dries, resistance across it increases, and eventually it will crack, creating a gas “short circuit” where hydrogen and oxygen combine directly, generating heat that will damage the fuel cell. If the water is evaporated too slowly, the electrodes will flood, preventing the reactants from reaching the catalyst and stopping the reaction. Methods to manage water in cells are being developed like electroosmotic pumps focusing on flow control. Just as in a combustion engine, a steady ratio between the reactant and oxygen is necessary to keep the fuel cell operating efficiently.
(in PEMFCs). In this type of fuel cell, the membrane must be hydrated, requiring water to be evaporated at precisely the same rate that it is produced. If water is evaporated too quickly, the membrane dries, resistance across it increases, and eventually it will crack, creating a gas “short circuit” where hydrogen and oxygen combine directly, generating heat that will damage the fuel cell. If the water is evaporated too slowly, the electrodes will flood, preventing the reactants from reaching the catalyst and stopping the reaction. Methods to manage water in cells are being developed like electroosmotic pumps focusing on flow control. Just as in a combustion engine, a steady ratio between the reactant and oxygen is necessary to keep the fuel cell operating efficiently. Temperature management. The same temperature must be maintained throughout the cell in order to prevent destruction of the cell through thermal loading. This is particularly challenging as the 2H 2 + O 2 -> 2H 2 O reaction is highly exothermic, so a large quantity of heat is generated within the fuel cell.
+ O -> 2H O reaction is highly exothermic, so a large quantity of heat is generated within the fuel cell. Durability, service life, and special requirements for some type of cells. Stationary fuel cell applications typically require more than 40,000 hours of reliable operation at a temperature of −35 °C to 40 °C (−31 °F to 104 °F), while automotive fuel cells require a 5,000-hour lifespan (the equivalent of 240,000 km (150,000 mi)) under extreme temperatures. Current service life is 7,300 hours under cycling conditions. Automotive engines must also be able to start reliably at −30 °C (−22 °F) and have a high power-to-volume ratio (typically 2.5 kW per liter).
Automotive engines must also be able to start reliably at −30 °C (−22 °F) and have a high power-to-volume ratio (typically 2.5 kW per liter). Limited carbon monoxide tolerance of some (non-PEDOT) cathodes.
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Phosphoric acid fuel cell (PAFC)
Phosphoric acid fuel cells (PAFC) were first designed and introduced in 1961 by G. V. Elmore and H. A. Tanner. In these cells phosphoric acid is used as a non-conductive electrolyte to pass positive hydrogen ions from the anode to the cathode. These cells commonly work in temperatures of 150 to 200 degrees Celsius. This high temperature will cause heat and energy loss if the heat is not removed and used properly. This heat can be used to produce steam for air conditioning systems or any other thermal energy consuming system.
The efficiency of phosphoric acid fuel cells is from 40 to about 80%. Phosphoric acid, the electrolyte used in PAFCs, is a non-conductive liquid acid which forces electrons to travel from anode to cathode through an external electrical circuit. Since the hydrogen ion production rate on the anode is small, platinum is used as catalyst to increase this ionization rate. A key disadvantage of these cells is the use of an acidic electrolyte. This increases the corrosion or oxidation of components exposed to phosphoric acid.
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High-temperature fuel cells
Solid oxide fuel cells (SOFCs) use a solid material, most commonly a ceramic material called yttria-stabilized zirconia (YSZ), as the electrolyte. Because SOFCs are made entirely of solid materials, they are not limited to the flat plane configuration of other types of fuel cells and are often designed as rolled tubes. They require high operating temperatures (800–1000 °C) and can be run on a variety of fuels including natural gas.
SOFCs are unique in that negatively charged oxygen ions travel from the cathode (positive side of the fuel cell) to the anode (negative side of the fuel cell) instead of positively charged hydrogen ions travelling from the anode to the cathode, as is the case in all other types of fuel cells. Oxygen gas is fed through the cathode, where it absorbs electrons to create oxygen ions.
The oxygen ions then travel through the electrolyte to react with hydrogen gas at the anode. The reaction at the anode produces electricity and water as by-products. Carbon dioxide may also be a by-product depending on the fuel, but the carbon emissions from an SOFC system are less than those from a fossil fuel combustion plant. The chemical reactions for the SOFC system can be expressed as follows:
Anode Reaction: 2H 2 + 2O2− → 2H 2 O + 4e− Cathode Reaction: O 2 + 4e– → 2O2− Overall Cell Reaction: 2H 2 + O 2 → 2H 2 O
SOFC systems can run on fuels other than pure hydrogen gas. However, since hydrogen is necessary for the reactions listed above, the fuel selected must contain hydrogen atoms. For the fuel cell to operate, the fuel must be converted into pure hydrogen gas. SOFCs are capable of internally reforming light hydrocarbons such as methane (natural gas), propane and butane. These fuel cells are at an early stage of development.
Challenges exist in SOFC systems due to their high operating temperatures. One such challenge is the potential for carbon dust to build up on the anode, which slows down the internal reforming process. Research to address this “carbon coking” issue at the University of Pennsylvania has shown that the use of copper-based cermet (heat-resistant materials made of ceramic and metal) can reduce coking and the loss of performance.
Another disadvantage of SOFC systems is slow start-up time, making SOFCs less useful for mobile applications. Despite these disadvantages, a high operating temperature provides an advantage by removing the need for a precious metal catalyst like platinum, thereby reducing cost. Additionally, waste heat from SOFC systems may be captured and reused, increasing the theoretical overall efficiency to as high as 80%–85%.
The high operating temperature is largely due to the physical properties of the YSZ electrolyte. As temperature decreases, so does the ionic conductivity of YSZ. Therefore, to obtain optimum performance of the fuel cell, a high operating temperature is required. According to their website, Ceres Power, a UK SOFC fuel cell manufacturer, has developed a method of reducing the operating temperature of their SOFC system to 500–600 degrees Celsius.
They replaced the commonly used YSZ electrolyte with a CGO (cerium gadolinium oxide) electrolyte. The lower operating temperature allows them to use stainless steel instead of ceramic as the cell substrate, which reduces cost and start-up time of the system.
Molten carbonate fuel cells (MCFCs) require a high operating temperature, 650 °C (1,200 °F), similar to SOFCs. MCFCs use lithium potassium carbonate salt as an electrolyte, and this salt liquefies at high temperatures, allowing for the movement of charge within the cell – in this case, negative carbonate ions.
Like SOFCs, MCFCs are capable of converting fossil fuel to a hydrogen-rich gas in the anode, eliminating the need to produce hydrogen externally. The reforming process creates CO 2 emissions. MCFC-compatible fuels include natural gas, biogas and gas produced from coal. The hydrogen in the gas reacts with carbonate ions from the electrolyte to produce water, carbon dioxide, electrons and small amounts of other chemicals.
The electrons travel through an external circuit creating electricity and return to the cathode. There, oxygen from the air and carbon dioxide recycled from the anode react with the electrons to form carbonate ions that replenish the electrolyte, completing the circuit. The chemical reactions for an MCFC system can be expressed as follows:
Anode Reaction: CO 3 2− + H 2 → H 2 O + CO 2 + 2e− Cathode Reaction: CO 2 + ½O 2 + 2e− → CO 3 2− Overall Cell Reaction: H 2 + ½O 2 → H 2 O
As with SOFCs, MCFC disadvantages include slow start-up times because of their high operating temperature. This makes MCFC systems not suitable for mobile applications, and this technology will most likely be used for stationary fuel cell purposes. The main challenge of MCFC technology is the cells’ short life span. The high-temperature and carbonate electrolyte lead to corrosion of the anode and cathode.
These factors accelerate the degradation of MCFC components, decreasing the durability and cell life. Researchers are addressing this problem by exploring corrosion-resistant materials for components as well as fuel cell designs that may increase cell life without decreasing performance.
MCFCs hold several advantages over other fuel cell technologies, including their resistance to impurities. They are not prone to “carbon coking”, which refers to carbon build-up on the anode that results in reduced performance by slowing down the internal fuel reforming process. Therefore, carbon-rich fuels like gases made from coal are compatible with the system.
The Department of Energy claims that coal, itself, might even be a fuel option in the future, assuming the system can be made resistant to impurities such as sulfur and particulates that result from converting coal into hydrogen. MCFCs also have relatively high efficiencies. They can reach a fuel-to-electricity efficiency of 50%, considerably higher than the 37–42% efficiency of a phosphoric acid fuel cell plant.
Comparison of fuel cell types
Glossary of Terms in table:
Anode : The electrode at which oxidation (a loss of electrons) takes place. For fuel cells and other galvanic cells, the anode is the negative terminal; for electrolytic cells (where electrolysis occurs), the anode is the positive terminal.
: The electrode at which oxidation (a loss of electrons) takes place. For fuel cells and other galvanic cells, the anode is the negative terminal; for electrolytic cells (where electrolysis occurs), the anode is the positive terminal. Aqueous solution : a : of, relating to, or resembling water b : made from, with, or by water.
: : of, relating to, or resembling water : made from, with, or by water. Catalyst : A chemical substance that increases the rate of a reaction without being consumed; after the reaction, it can potentially be recovered from the reaction mixture and is chemically unchanged. The catalyst lowers the activation energy required, allowing the reaction to proceed more quickly or at a lower temperature. In a fuel cell, the catalyst facilitates the reaction of oxygen and hydrogen. It is usually made of platinum powder very thinly coated onto carbon paper or cloth. The catalyst is rough and porous so the maximum surface area of the platinum can be exposed to the hydrogen or oxygen. The platinum-coated side of the catalyst faces the membrane in the fuel cell.
: A chemical substance that increases the rate of a reaction without being consumed; after the reaction, it can potentially be recovered from the reaction mixture and is chemically unchanged. The catalyst lowers the activation energy required, allowing the reaction to proceed more quickly or at a lower temperature. In a fuel cell, the catalyst facilitates the reaction of oxygen and hydrogen. It is usually made of platinum powder very thinly coated onto carbon paper or cloth. The catalyst is rough and porous so the maximum surface area of the platinum can be exposed to the hydrogen or oxygen. The platinum-coated side of the catalyst faces the membrane in the fuel cell. Cathode: The electrode at which reduction (a gain of electrons) occurs. For fuel cells and other galvanic cells, the cathode is the positive terminal; for electrolytic cells (where electrolysis occurs), the cathode is the negative terminal.
The electrode at which reduction (a gain of electrons) occurs. For fuel cells and other galvanic cells, the cathode is the positive terminal; for electrolytic cells (where electrolysis occurs), the cathode is the negative terminal. Electrolyte : A substance that conducts charged ions from one electrode to the other in a fuel cell, battery, or electrolyzer.
: A substance that conducts charged ions from one electrode to the other in a fuel cell, battery, or electrolyzer. Fuel Cell Stack : Individual fuel cells connected in a series. Fuel cells are stacked to increase voltage.
: Individual fuel cells connected in a series. Fuel cells are stacked to increase voltage. Matrix : something within or from which something else originates, develops, or takes form.
: something within or from which something else originates, develops, or takes form. Membrane : The separating layer in a fuel cell that acts as electrolyte (an ion-exchanger) as well as a barrier film separating the gases in the anode and cathode compartments of the fuel cell.
: The separating layer in a fuel cell that acts as electrolyte (an ion-exchanger) as well as a barrier film separating the gases in the anode and cathode compartments of the fuel cell. Molten Carbonate Fuel Cell (MCFC) : A type of fuel cell that contains a molten carbonate electrolyte. Carbonate ions (CO 3 2− ) are transported from the cathode to the anode. Operating temperatures are typically near 650 °C. [46]
: A type of fuel cell that contains a molten carbonate electrolyte. Carbonate ions (CO ) are transported from the cathode to the anode. Operating temperatures are typically near 650 °C. Phosphoric acid fuel cell (PAFC) : A type of fuel cell in which the electrolyte consists of concentrated phosphoric acid (H 3 PO 4 ). Protons (H+) are transported from the anode to the cathode. The operating temperature range is generally 160–220 °C.
: A type of fuel cell in which the electrolyte consists of concentrated phosphoric acid (H PO ). Protons (H+) are transported from the anode to the cathode. The operating temperature range is generally 160–220 °C. Polymer Electrolyte Membrane (PEM) : A fuel cell incorporating a solid polymer membrane used as its electrolyte. Protons (H+) are transported from the anode to the cathode. The operating temperature range is generally 60–100 °C.
: A fuel cell incorporating a solid polymer membrane used as its electrolyte. Protons (H+) are transported from the anode to the cathode. The operating temperature range is generally 60–100 °C. Solid Oxide Fuel Cell (SOFC): A type of fuel cell in which the electrolyte is a solid, nonporous metal oxide, typically zirconium oxide (ZrO 2 ) treated with Y 2 O 3 , and O 2− is transported from the cathode to the anode. Any CO in the reformate gas is oxidized to CO 2 at the anode. Temperatures of operation are typically 800–1,000 °C.
(SOFC): A type of fuel cell in which the electrolyte is a solid, nonporous metal oxide, typically zirconium oxide (ZrO ) treated with Y O , and O is transported from the cathode to the anode. Any CO in the reformate gas is oxidized to CO at the anode. Temperatures of operation are typically 800–1,000 °C. Solution: a: an act or the process by which a solid, liquid, or gaseous substance is homogeneously mixed with a liquid or sometimes a gas or solid, b : a homogeneous mixture formed by this process; especially : a single-phase liquid system, c : the condition of being dissolved
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Theoretical maximum efficiency
The energy efficiency of a system or device that converts energy is measured by the ratio of the amount of useful energy put out by the system (“output energy”) to the total amount of energy that is put in (“input energy”) or by useful output energy as a percentage of the total input energy. In the case of fuel cells, useful output energy is measured in electrical energy produced by the system. Input energy is the energy stored in the fuel. According to the U.S. Department of Energy, fuel cells are generally between 40–60% energy efficient. This is higher than some other systems for energy generation.
For example, the typical internal combustion engine of a car is about 25% energy efficient. In combined heat and power (CHP) systems, the heat produced by the fuel cell is captured and put to use, increasing the efficiency of the system to up to 85–90%.
The theoretical maximum efficiency of any type of power generation system is never reached in practice, and it does not consider other steps in power generation, such as production, transportation and storage of fuel and conversion of the electricity into mechanical power. However, this calculation allows the comparison of different types of power generation.
The maximum theoretical energy efficiency of a fuel cell is 83%, operating at low power density and using pure hydrogen and oxygen as reactants (assuming no heat recapture) According to the World Energy Council, this compares with a maximum theoretical efficiency of 58% for internal combustion engines. While these efficiencies are not approached in most real world applications, high-temperature fuel cells (solid oxide fuel cells or molten carbonate fuel cells) can theoretically be combined with gas turbines to allow stationary fuel cells to come closer to the theoretical limit.
A gas turbine would capture heat from the fuel cell and turn it into mechanical energy to increase the fuel cell’s operational efficiency. This solution has been predicted to increase total efficiency to as much as 70%.
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In practice
The tank-to-wheel efficiency of a fuel-cell vehicle is greater than 45% at low loads and shows average values of about 36% when a driving cycle like the NEDC (New European Driving Cycle) is used as test procedure. The comparable NEDC value for a Diesel vehicle is 22%. In 2008 Honda released a demonstration fuel cell electric vehicle (the Honda FCX Clarity) with fuel stack claiming a 60% tank-to-wheel efficiency.
It is also important to take losses due to fuel production, transportation, and storage into account. Fuel cell vehicles running on compressed hydrogen may have a power-plant-to-wheel efficiency of 22% if the hydrogen is stored as high-pressure gas, and 17% if it is stored as liquid hydrogen. Fuel cells cannot store energy like a battery, except as hydrogen, but in some applications, such as stand-alone power plants based on discontinuous sources such as solar or wind power, they are combined with electrolyzers and storage systems to form an energy storage system.
Most hydrogen, however, is produced by steam methane reforming, and so most hydrogen production emits carbon dioxide. The overall efficiency (electricity to hydrogen and back to electricity) of such plants (known as round-trip efficiency), using pure hydrogen and pure oxygen can be “from 35 up to 50 percent”, depending on gas density and other conditions. While a much cheaper lead–acid battery might return about 90%, the electrolyzer/fuel cell system can store indefinite quantities of hydrogen, and is therefore better suited for long-term storage.
Solid-oxide fuel cells produce exothermic heat from the recombination of the oxygen and hydrogen. The ceramic can run as hot as 800 degrees Celsius. This heat can be captured and used to heat water in a micro combined heat and power (m-CHP) application. When the heat is captured, total efficiency can reach 80–90% at the unit, but does not consider production and distribution losses. CHP units are being developed today for the European home market.
Professor Jeremy P. Meyers, in the Electrochemical Society journal Interface in 2008, wrote, “While fuel cells are efficient relative to combustion engines, they are not as efficient as batteries, due primarily to the inefficiency of the oxygen reduction reaction (and … the oxygen evolution reaction, should the hydrogen be formed by electrolysis of water)…. [T]hey make the most sense for operation disconnected from the grid, or when fuel can be provided continuously.
For applications that require frequent and relatively rapid start-ups … where zero emissions are a requirement, as in enclosed spaces such as warehouses, and where hydrogen is considered an acceptable reactant, a [PEM fuel cell] is becoming an increasingly attractive choice [if exchanging batteries is inconvenient]”. In 2013 military organizations are evaluating fuel cells to significantly reduce the battery weight carried by soldiers.
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Power
Stationary fuel cells are used for commercial, industrial and residential primary and backup power generation. Fuel cells are very useful as power sources in remote locations, such as spacecraft, remote weather stations, large parks, communications centers, rural locations including research stations, and in certain military applications. A fuel cell system running on hydrogen can be compact and lightweight, and have no major moving parts. Because fuel cells have no moving parts and do not involve combustion, in ideal conditions they can achieve up to 99.9999% reliability. This equates to less than one minute of downtime in a six-year period.
Since fuel cell electrolyzer systems do not store fuel in themselves, but rather rely on external storage units, they can be successfully applied in large-scale energy storage, rural areas being one example.There are many different types of stationary fuel cells so efficiencies vary, but most are between 40% and 60% energy efficient.
However, when the fuel cell’s waste heat is used to heat a building in a co-generation system this efficiency can increase to 85%.This is significantly more efficient than traditional coal power plants, which are only about one third energy efficient. Assuming production at scale, fuel cells could save 20–40% on energy costs when used in co-generation systems.
They are also much cleaner than traditional power generation; a fuel cell power plant using natural gas as a hydrogen source would create less than one ounce of pollution (other than CO 2) for every 1,000 kW·h produced, compared to 25 pounds of pollutants generated by conventional combustion systems. Fuel Cells also produce 97% less nitrogen oxide emissions than conventional coal-fired power plants.
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Automobiles
Although there are currently no fuel cell vehicles available for commercial sale, over 20 fuel cell electric vehicle (FCEV) prototypes and demonstration cars have been released since 2009. Demonstration models include the Honda FCX Clarity, Toyota FCHV-adv, and Mercedes-Benz F-Cell. As of June 2011 demonstration FCEVs had driven more than 4,800,000 km (3,000,000 mi), with more than 27,000 refuelings.
Demonstration fuel cell vehicles have been produced with “a driving range of more than 400 km (250 mi) between refueling”. They can be refueled in less than 5 minutes. The U.S. Department of Energy’s Fuel Cell Technology Program claims that, as of 2011, fuel cells achieved 53–59% efficiency at one-quarter power and 42–53% vehicle efficiency at full power,and a durability of over 120,000 km (75,000 mi) with less than 10% degradation.
In a Well-to-Wheels simulation analysis, that “did not address the economics and market constraints”, General Motors and its partners estimated that per mile traveled, a fuel cell electric vehicle running on compressed gaseous hydrogen produced from natural gas could use about 40% less energy and emit 45% less greenhouse gasses than an internal combustion vehicle.
A lead engineer from the Department of Energy whose team is testing fuel cell cars said in 2011 that the potential appeal is that “these are full-function vehicles with no limitations on range or refueling rate so they are a direct replacement for any vehicle. For instance, if you drive a full sized SUV and pull a boat up into the mountains, you can do that with this technology and you can’t with current battery-only vehicles, which are more geared toward city driving.”
Some experts believe, however, that fuel cell cars will never become economically competitive with other technologies or that it will take decades for them to become profitable. “Only about 25% of the power generated from wind, water, or sun is converted to practical use.” The study further noted that “Electricity obtained from hydrogen fuel cells appears to be four times as expensive as electricity drawn from the electrical transmission grid. … Because of the high energy losses [hydrogen] cannot compete with electricity.”
Furthermore, the study found: “Natural gas reforming is not a sustainable solution”. “The large amount of energy required to isolate hydrogen from natural compounds (water, natural gas, biomass), package the light gas by compression or liquefaction, transfer the energy carrier to the user, plus the energy lost when it is converted to useful electricity with fuel cells, leaves around 25% for practical use.”
Boeing researchers and industry partners throughout Europe conducted experimental flight tests in February 2008 of a manned airplane powered only by a fuel cell and lightweight batteries. The fuel cell demonstrator airplane, as it was called, used a proton exchange membrane (PEM) fuel cell/lithium-ion battery hybrid system to power an electric motor, which was coupled to a conventional propeller.
In 2003, the world’s first propeller-driven airplane to be powered entirely by a fuel cell was flown. The fuel cell was a unique FlatStackTM stack design, which allowed the fuel cell to be integrated with the aerodynamic surfaces of the plane.
There have been several fuel-cell-powered unmanned aerial vehicles (UAV). A Horizon fuel cell UAV set the record distance flown for a small UAV in 2007. The military is especially interested in this application because of the low noise, low thermal signature and ability to attain high altitude. In 2009 the Naval Research Laboratory’s (NRL’s) Ion Tiger utilized a hydrogen-powered fuel cell and flew for 23 hours and 17 minutes.
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Boats
The world’s first fuel-cell boat HYDRA used an AFC system with 6.5 kW net output. Iceland has committed to converting its vast fishing fleet to use fuel cells to provide auxiliary power by 2015 and, eventually, to provide primary power in its boats. Amsterdam recently introduced its first fuel-cell-powered boat that ferries people around the city’s famous and beautiful canals.
Submarines
The Type 212 submarines of the German and Italian navies use fuel cells to remain submerged for weeks without the need to surface.
The U212A is a non-nuclear submarine developed by German naval shipyard Howaldtswerke Deutsche Werft. The system consists of nine PEM fuel cells, providing between 30 kW and 50 kW each. The ship is silent giving it an advantage in the detection of other submarines. A Recent naval paper has theorized about the the possibility of a Nuclear-Fuel Cell Hybrid whereby the fuel cell is used when silent operations are required and then replenished from the Nuclear reactor (and water). Such a system could potentially give a submarine weeks of stealth capability at a time with the endurance of a Nuclear reactor. It is not known if any such submarines have been built.
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veteranstoday--2020-09-05--VT Nuclear Education: HAARP

VT Nuclear Education: HAARP

The plasma of this typical example might be employed to modify or disrupt microwave transmissions of satellites .
If less than total black-out of transmission is desired ( e.g.
, scrambling by phase shifting digital signals ) , the density of the plasma ( Ne ) need only be at lea about 106 joules per cubic centimeter for a plasma originating at an altitude of from about 250 to about 400 km accordingly less energy ( i.e.
, electromagnetic radiation ) , e.g.
, l08 joules need be provided .
Likewise , if the density Ne is on the order @ @ @ @ @ @ @ will provide a reflecting surface for VHF frequency ’ s and can be used to enhance , interfere with , or otherwise modify communication transmissions .
It can be seen from the foregoing that by appropriate application of various aspects of this invention at strategic locations and with adequate power sources , a means and method is provided to cause interference with or even total disruption of communications over a very large portion of the earth .
This invention could be employed to disrupt not only land based communications , both civilian and @ @ @ @ @ @ @ sea communications ( both surface and subsurface ) .
This would have significant military implications , particularly as a barrier to or confusing factor for hostile missiles or airplanes .
The belt or belts of enhanced ionization produced by the method and apparatus of this invention , particularly if set up over Northern Alaska and Canada , could be employed as an early warning device , as well as a communications disruption medium .
Further , the simple ability to produce such a situation in a practical time period can by itself be @ @ @ @ @ @ @ The ideal combination of suitable field lines intersecting the earth ’ s surface at the point where substantial fuel sources are available for generation of very large quantities of electromagnetic power , such as the North Slope of Alaska , provides the where withal to accomplish the foregoing in a practical time period , e.g.
, strategic requirements could necessitate achievable in the desired altered regions in time periods of two minutes or less and this is achievable with this invention , especially when the combination of natural gas and magneto-hydrodynamic , gas @ @ @ @ @ @ @ are employed at the point where the useful field lines intersect the earth ’ s surface .
One feature of this invention which sates a basic requirement of a weapon system , i.e.
, continuous operability , is that small amounts of power can be generated for operability checking purposes .
Further , the exploitation of this invention , since the main electromagnetic beam which generates the enhanced ionized belt of this invention can be modulated itself and/or one or more additional electromagnetic radiation waves can be impinged on the ionized region formed @ @ @ @ @ @ @ in greater detail herein after with respect to FIG .
4 , a substantial amount of randomly modulated signals of very large power magnitude can be generated in a highly nonlinear mode .
This can cause confusion of or interference with or even complete disruption of guidance systems employed by an enemy .

The plasma of this typical example might be employed to modify or disrupt microwave transmissions of satellites. If less than total black-out of transmission is desired (e.g., scrambling by phase shifting digital signals), the density of the plasma (Ne) need only be at lea about 106 joules per cubic centimeter for a plasma originating at an altitude of from about 250 to about 400 km accordingly less energy (i.e., electromagnetic radiation), e.g., l08 joules need be provided.
HAARP Patent
Likewise, if the density Ne is on the order of 108, a properly positioned plume will provide a reflecting surface for VHF frequency’s and can be used to enhance, interfere with, or otherwise modify communication transmissions. It can be seen from the foregoing that by appropriate application of various aspects of this invention at strategic locations and with adequate power sources, a means and method is provided to cause interference with or even total disruption of communications over a very large portion of the earth.
This invention could be employed to disrupt not only land based communications, both civilian and military, but also airborne communications and sea communications (both surface and subsurface). This would have significant military implications, particularly as a barrier to or confusing factor for hostile missiles or airplanes.
The belt or belts of enhanced ionization produced by the method and apparatus of this invention, particularly if set up over Northern Alaska and Canada, could be employed as an early warning device, as well as a communications disruption medium. Further, the simple ability to produce such a situation in a practical time period can by itself be a deterring force to hostile action.
The ideal combination of suitable field lines intersecting the earth’s surface at the point where substantial fuel sources are available for generation of very large quantities of electromagnetic power, such as the North Slope of Alaska, provides the where withal to accomplish the foregoing in a practical time period, e.g., strategic requirements could necessitate achievable in the desired altered regions in time periods of two minutes or less and this is achievable with this invention, especially when the combination of natural gas and magneto-hydrodynamic, gas turbine, fuel cell EGD electric generators are employed at the point where the useful field lines intersect the earth’s surface.
One feature of this invention which sates a basic requirement of a weapon system, i.e., continuous operability, is that small amounts of power can be generated for operability checking purposes. Further, the exploitation of this invention, since the main electromagnetic beam which generates the enhanced ionized belt of this invention can be modulated itself and/or one or more additional electromagnetic radiation waves can be impinged on the ionized region formed by this invention as will be described in greater detail herein after with respect to FIG. 4, a substantial amount of randomly modulated signals of very large power magnitude can be generated in a highly nonlinear mode. This can cause confusion of or interference with or even complete disruption of guidance systems employed by an enemy.


veteranstoday--2020-09-05--VT Nuclear Education: LENR, Abandoning Science for a Circus Act

Whereas fast neutrons create one hell of a mess when they collide with the nuclei of other atoms , LENR ’ s slow neutrons don ’ t generate ionizing radiation or radioactive waste .
It is because of this sedate gentility that LENR lends itself very well to vehicular and at-home nuclear reactors that provide both heat and electricity .
According to NASA , 1 % of the world ’ s nickel production could meet the world ’ s energy needs , at a quarter of the cost of coal .
NASA also mentions , almost as an aside , @ @ @ @ @ @ @ carbon instead of nickel , with the nuclear reaction turning carbon into nitrogen .
“ You ’ re not sequestering carbon , you ’ re totally removing carbon from the system , ” says Joseph Zawodny , a NASA scientist involved with the work on LENR .
So why don ’ t we have LENR reactors yet ?
Just like fusion , it is proving hard to build a LENR system that produces more energy than the energy required to begin the reaction .
In this case , NASA says that the 5-30THz @ @ @ @ @ @ @ is hard to efficiently produce .
As we ’ ve reported over the last couple of years , though , strong advances are being made in the generation and control of terahertz radiation .
Other labs outside of NASA are working on cold fusion and LENR , too : “ Several labs have blown up studying LENR and windows have melted , ” says NASA scientist Dennis Bushnell , proving that “ when the conditions are ‘ right ’ prodigious amounts of energy can be produced and released.
” I am sad – @ @ @ @ @ @ @ NASA scientists have caught cold fusion madness .
As is so often the case with companies and research groups that get involved in this fruitless enterprise , they tend to make their case by first pointing out how nice it would be to have a clean , cheap , safe , effectively limitless source of power .
Who could say no to that ?
Here ’ s a word of caution : anytime anyone , especially a scientist , starts by telling you about glorious , nigh-unbelievable futuristic applications of their idea , @ @ @ @ @ @ @ , for example , is promoting a cold fusion scheme that they say will power your house and car , and even a space plane that is apparently under development , despite the fact that cold fusion power supplies don ’ t exist yet and almost certainly never will .
And if that ’ s not enough , NASA ’ s brand of cold fusion can solve our climate change problems by converting carbon directly into nitrogen .
The one hitch in the plan , unfortunately , is that they ’ re going @ @ @ @ @ @ @ established physics to make it happen .
To say the least , I wouldn ’ t count on it .
Cold fusion that doesn ’ t involve muons , on the other hand , doesn ’ t work .
In fact , the very same physics principles that make muon-catalyzed fusion possible are the ones that guarantee that the muon-less version isn ’ t possible .
To get around the problem presented by nature and her physical laws , NASA ’ s scientists have joined other cold fusion advocates in rebranding their work @ @ @ @ @ @ @ Low Energy Nuclear Reactions ) , and backing it up with various sketchy theories .
The main theory currently in fashion among cold fusion people is the Widom-Larsen LENR theory , which claims that neutrons can result from interactions with “ heavy electrons ” and protons in a lump of material in a cold fusion experiment .
These neutrons , so the argument goes , can then be absorbed in a material ( copper is a popular choice ) which becomes unstable and decays to form a lighter material ( nickel , assuming @ @ @ @ @ @ @ off energy in the process .
At least one paper argues that Widom and Larsen made some serious errors in their calculations that thoroughly undermine their theory .
But even if you assume the Widom-Larsen paper is correct , then there should be detectable neutrons produced in cold fusion experiments .
( Coincidentally , it ’ s primarily because no neutrons were detected in the original cold fusion experiments of Pons and Fleischmannthat physicists were first clued into the fact no fusion was happening at all . )
Those that don ’ t @ @ @ @ @ @ @ atoms would also lead to detectable radiation as the neutron-activated portions of the material decays .
Either way , it would be pretty dangerous to be near an experiment like that , if it worked .
The fact that cold fusion researchers are alive is fairly good evidence that their experiments aren ’ t doing what they think they ’ re doing .
But if you ’ re willing to believe Widom-Larsen , and you suspend your disbelief long enough to accept that the neutrons exclusively stay in the sample for some reason @ @ @ @ @ @ @ a result dosn ’ t include any radiation , it should still be pretty easy to determine if the experiments work .
All you ’ d have to do is look for nickel in a sample that initially consisted of pure copper .
If published proof exists , I haven ’ t found it yet ( please send links to peer-reviewed publications , if you ’ ve seen something ) .
Instead , people like NASA ’ s Dennis Bushnell are happy with decidedly unscientific evidence for cold fusion .
Among other things @ @ @ @ @ @ @ .
several labs have blown up studying LENR and windows have melted , indicating when the conditions are “ right ” prodigious amounts of energy can be produced and released.
” Of course , chemical reactions can blow things up and melt glass too .
There ’ s no reason to conclude nuclear reactions were responsible .
And it certainly isn ’ t publishable proof of cold fusion .
Considering that most of these experiments involve hydrogen gas and electricity , it ’ s not at all surprising that labs go up in @ @ @ @ @ @ @ note , a recent article in Forbes magazine reported that Lewis Larsen , of the above-mentioned Widom-Larsen theory , claims that measurements of the isotopes of mercury in compact fluorescent bulbs indicate that LENR reactions are taking place in light fixtures everywhere .
If only it were true , it would offer serious support for the Widom-Larsen theory .
It ’ s too bad the paper Larsen cites says nothing of the sort .
According to an article in Chemical and Engineering News , the scientists who performed the study of gas in @ @ @ @ @ @ @ that some mercury isotopes are absorbed in the glass of the bulbs more readily than others .
The isotope ratio inside isn ’ t changing because of nuclear reactions , but instead by soaking into the glass at different rates .
Sorry Lewis Larsen , nice try .

…by Jeff Smith, Science Editor
The cold fusion dream lives on: NASA is developing cheap, clean, low-energy nuclear reaction (LENR) technology that could eventually see cars, planes, and homes powered by small, safe nuclear reactors.
When we think of nuclear power, there are usually just two options: fission and fusion. Fission, which creates huge amounts of heat by splitting larger atoms into smaller atoms, is what currently powers every nuclear reactor on Earth.
Fusion is the opposite, creating vast amounts of energy by fusing atoms of hydrogen together, but we’re still many years away from large-scale, commercial fusion reactors. (See: 500MW from half a gram of hydrogen: The hunt for fusion power heats up.)
LENR is absolutely nothing like either fission or fusion. Where fission and fusion are underpinned by strong nuclear force, LENR harnesses power from weak nuclear force — but capturing this energy is difficult. So far, NASA’s best effort involves a nickel lattice and hydrogen ions. The hydrogen ions are sucked into the nickel lattice, and then the lattice is oscillated at a very high frequency (between 5 and 30 terahertz).
This oscillation excites the nickel’s electrons, which are forced into the hydrogen ions (protons), forming slow-moving neutrons. The nickel immediately absorbs these neutrons, making it unstable. To regain its stability, the nickel strips a neutron of its electron so that it becomes a proton — a reaction that turns the nickel into copper and creates a lot of energy in the process.
The key to LENR’s cleanliness and safety seems to be the slow-moving neutrons. Whereas fission creates fast neutrons (neutrons with energies over 1 megaelectron volt), LENR utilizes neutrons with an energy below 1eV — less than a millionth of the energy of a fast neutron.
Whereas fast neutrons create one hell of a mess when they collide with the nuclei of other atoms, LENR’s slow neutrons don’t generate ionizing radiation or radioactive waste. It is because of this sedate gentility that LENR lends itself very well to vehicular and at-home nuclear reactors that provide both heat and electricity.
According to NASA, 1% of the world’s nickel production could meet the world’s energy needs, at a quarter of the cost of coal. NASA also mentions, almost as an aside, that the lattice could be formed of carbon instead of nickel, with the nuclear reaction turning carbon into nitrogen. “You’re not sequestering carbon, you’re totally removing carbon from the system,” says Joseph Zawodny, a NASA scientist involved with the work on LENR.
So why don’t we have LENR reactors yet? Just like fusion, it is proving hard to build a LENR system that produces more energy than the energy required to begin the reaction. In this case, NASA says that the 5-30THz frequency required to oscillate the nickel lattice is hard to efficiently produce.
As we’ve reported over the last couple of years, though, strong advances are being made in the generation and control of terahertz radiation. Other labs outside of NASA are working on cold fusion and LENR, too: “Several labs have blown up studying LENR and windows have melted,” says NASA scientist Dennis Bushnell, proving that “when the conditions are ‘right’ prodigious amounts of energy can be produced and released.”
I think it’s still fairly safe to say that the immediate future of power generation, and meeting humanity’s burgeoning energy needs, lies in fission and fusion (See: Nuclear power is our only hope.) But who knows: With LENR, maybe there’s hope for cold fusion yet
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I am sad – horrified really – to learn that some NASA scientists have caught cold fusion madness. As is so often the case with companies and research groups that get involved in this fruitless enterprise, they tend to make their case by first pointing out how nice it would be to have a clean, cheap, safe, effectively limitless source of power. Who could say no to that?
NASA Langley scientists are hoping to build spacecraft powered with cold fusion. Image courtesy of NASA.
Here’s a word of caution: anytime anyone, especially a scientist, starts by telling you about glorious, nigh-unbelievable futuristic applications of their idea, be very, very skeptical.
NASA, for example, is promoting a cold fusion scheme that they say will power your house and car, and even a space plane that is apparently under development, despite the fact that cold fusion power supplies don’t exist yet and almost certainly never will. And if that’s not enough, NASA’s brand of cold fusion can solve our climate change problems by converting carbon directly into nitrogen.
The one hitch in the plan, unfortunately, is that they’re going to have to violate some very well established physics to make it happen. To say the least, I wouldn’t count on it.
To be clear, cold fusion does indeed work – provided you use a heavier cousin of the electron, known as a muon, to make it happen. There is no question that muon-catalyzed fusion is a perfectly sound, well-understood process that would be an abundant source of energy, if only we could find or create a cheap source of muons. Unfortunately, it takes way more energy to create the muons that go into muon-catalyzed fusion than comes out of the reaction.
Cold fusion that doesn’t involve muons, on the other hand, doesn’t work. In fact, the very same physics principles that make muon-catalyzed fusion possible are the ones that guarantee that the muon-less version isn’t possible.
To get around the problem presented by nature and her physical laws, NASA’s scientists have joined other cold fusion advocates in rebranding their work under the deceptively scientific moniker LENR (Low Energy Nuclear Reactions), and backing it up with various sketchy theories.
The main theory currently in fashion among cold fusion people is the Widom-Larsen LENR theory, which claims that neutrons can result from interactions with “heavy electrons” and protons in a lump of material in a cold fusion experiment.
These neutrons, so the argument goes, can then be absorbed in a material (copper is a popular choice) which becomes unstable and decays to form a lighter material (nickel, assuming you start with copper), giving off energy in the process.
At least one paper argues that Widom and Larsen made some serious errors in their calculations that thoroughly undermine their theory. But even if you assume the Widom-Larsen paper is correct, then there should be detectable neutrons produced in cold fusion experiments. (Coincidentally, it’s primarily because no neutrons were detected in the original cold fusion experiments of Pons and Fleischmannthat physicists were first clued into the fact no fusion was happening at all.)
Some proponents claim that the neutrons produced in the Widom-Larsen theory are trapped in the sample material and rapidly absorbed by atoms. But because the neutrons are formed at room temperature, they should have energies typical of thermal neutrons, which move on average at about 2000 meters a second. That means that a large fraction of them should escape the sample, and be easily detectable.
Those that don’t escape, but instead are absorbed by atoms would also lead to detectable radiation as the neutron-activated portions of the material decays. Either way, it would be pretty dangerous to be near an experiment like that, if it worked. The fact that cold fusion researchers are alive is fairly good evidence that their experiments aren’t doing what they think they’re doing.
But if you’re willing to believe Widom-Larsen, and you suspend your disbelief long enough to accept that the neutrons exclusively stay in the sample for some reason, and that the energy released as a result dosn’t include any radiation, it should still be pretty easy to determine if the experiments work. All you’d have to do is look for nickel in a sample that initially consisted of pure copper. If published proof exists, I haven’t found it yet (please send links to peer-reviewed publications, if you’ve seen something).
Instead, people like NASA’s Dennis Bushnell are happy with decidedly unscientific evidence for cold fusion. Among other things, Bushnell notes that ” . . . several labs have blown up studying LENR and windows have melted, indicating when the conditions are “right” prodigious amounts of energy can be produced and released.”
Of course, chemical reactions can blow things up and melt glass too. There’s no reason to conclude nuclear reactions were responsible. And it certainly isn’t publishable proof of cold fusion. Considering that most of these experiments involve hydrogen gas and electricity, it’s not at all surprising that labs go up in flames on occasion.
On a related note, a recent article in Forbes magazine reported that Lewis Larsen, of the above-mentioned Widom-Larsen theory, claims that measurements of the isotopes of mercury in compact fluorescent bulbs indicate that LENR reactions are taking place in light fixtures everywhere. If only it were true, it would offer serious support for the Widom-Larsen theory.
It’s too bad the paper Larsen cites says nothing of the sort. According to an article in Chemical and Engineering News, the scientists who performed the study of gas in fluorescent bulbs were motivated by the knowledge that some mercury isotopes are absorbed in the glass of the bulbs more readily than others. The isotope ratio inside isn’t changing because of nuclear reactions, but instead by soaking into the glass at different rates. Sorry Lewis Larsen, nice try.
Added note: I want to thank Steven Corneliussen of Physics Today for his timely summary of the recent cold fusion coverage in Forbes. I am even more grateful to Jeff McMahon of Forbes for his shockingly credulous reporting of the NASA Langley cold fusion program – it would have been nice if he’d interviewed someone with conventional views of physics, but at least he got the word out.
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Tiny Nuclear Reactions Inside Compact Fluorescent Bulbs?