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1 mars 2011 2 01 /03 /mars /2011 03:19

Fuel cells come in many varieties; however, they all work in the same general manner. They are made up of three segments which are sandwiched together: the anode, the electrolyte, and the cathode   (Dell XPS M1210 Batteryhttp://www.hdd-shop.co.uk .

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  Dell Studio XPS 1640 Battery .

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  Dell Vostro 1710 Battery .

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.

The most important design features in a fuel cell are  Dell KM958 battery :

  • 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, which breaks down the fuel into electrons and ions. The anode catalyst is usually made up of very fine platinum powder  Dell Studio 1555 battery .
  • The cathode catalyst, which turns the ions into the waste chemicals like water or carbon dioxide. The cathode catalyst is often made up of nickel     Sony VGP-BPS13 battery .

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  Sony VGP-BPS13/B battery
  • Ohmic loss (voltage drop due to resistance of the cell components and interconnects)
  • Mass transport loss (depletion of reactants at catalyst sites under high loads, causing rapid loss of voltage)  Sony VGP-BPS13/S battery .

To deliver the desired amount of energy, the fuel cells can be combined in series and parallel circuits, where series yields higher voltage, and parallel allows a higher current to be supplied. Such a design is called a fuel cell stack. The cell surface area can be increased, to allow stronger current from each cell  Sony VGP-BPS13A/B battery .

roton exchange membrane fuel cells

In the archetypal hydrogen–oxygen proton exchange membrane fuel cell (PEMFC) design, a proton-conducting polymer membrane, (the electrolyte), separates the anode and cathode sides  Sony VGP-BPS13B/B battery .

This was called a "solid polymer electrolyte fuel cell" (SPEFC) in the early 1970s, before the proton exchange mechanism was well-understood. (Notice that "polymer electrolyte membrane" and "proton exchange mechanism" result in the same acronym Sony VGP-BPL9 battery .)

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 is commonly referred to as multi-facilitated proton membranes  Sony VGP-BPS13B/B battery .

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  Sony VGP-BPL15 battery

— in this example, the only waste product, either liquid or vapor.

In addition to this pure hydrogen type, there are hydrocarbon fuels for fuel cells, including diesel, methanol (see: direct-methanol fuel cells and indirect methanol fuel cells) and chemical hydrides  Dell Inspiron E1505 battery .

The waste products with these types of fuel are carbon dioxide and water.

The different components of a PEMFC are (i) bipolar plates, (ii) electrodes, (iii) catalyst, (iv) membrane, and (v) the necessary hardwares  Dell Latitude E6400 battery .

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  HP Pavilion dv6000 Battery .

The membrane electrode assembly (MEA), is referred as the heart of the PEMFC and 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  SONY VAIO VGN-FZ Battery .

Proton exchange membrane fuel cell design issues

  • Costs. In 2002, typical fuel cell systems cost US$1000 per kilowatt of electric power output. In 2009, the Department of Energy reported that 80-kW automotive fuel cell system costs in volume production (projected to 500,000 units per year) are $61 per kilowatt  SONY VAIO VGN-FZ18 Battery .
  • The goal is $35 per kilowatt. In 2008 UTC Power has 400 kW stationary fuel cells for $1,000,000 per 400 kW installed costs. The goal is to reduce the cost in order to compete with current market technologies including gasoline internal combustion engines  SONY VAIO VGN-FZ21E Battery .
  • 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  SONY VAIO VGN-FW31J Battery - 5200mAh/7800mAh/10400mAh, 11.10V .
  • Ballard Power Systems have experiments with a catalyst enhanced with carbon silk which allows a 30% reduction (1 mg/cm² to 0.7 mg/cm²) in platinum usage without reduction in performance. Monash University, Melbourne uses PEDOT as a cathodeSONY VAIO VGN-FW31J Battery - 5200mAh/7800mAh/10400mAh, 11.10V .
  • The production costs of the PEM (proton exchange membrane). The Nafion membrane currently costs $566/m². In 2005 Ballard Power Systems announced that its fuel cells will use Solupor, a porous polyethylene film patented by DSM SONY VAIO VGN-FW21E Battery .
  • 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  SONY VAIO VGN-NR11S/S Battery ,
  • 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  SONY VAIO VGN-NR11M/S Battery .
  • 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 efficientlySONY VAIO VGN-NR11Z/S Battery .
  • 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 2H2 + O2 -> 2H2O reaction is highly exothermic, so a large quantity of heat is generated within the fuel cell  SONY VAIO VGN-NR11Z/T Battery .
  • 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 150,000 miles) under extreme temperatures Sony VAIO VGN-FZ21E Battery .
  • 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).
  • Limited carbon monoxide tolerance of some (non-PEDOT) cathodes  Sony VAIO VGN-FW21E Battery .

High temperature fuel cells

A solid oxide fuel cell (SOFC) is extremely advantageous “because of a possibility of using a wide variety of fuel”. Unlike most other fuel cells which only use hydrogen, SOFCs can run on hydrogen, butane, methanol, and other petroleum products Sony VAIO VGN-NR11S/S Battery .

The different fuels each have their own chemistry.

For SOFC methanol fuel cells, on the anode side, a catalyst breaks methanol and water down to form carbon dioxide, hydrogen ions, and free electrons   Sony VAIO VGN-NR11Z/S Battery .

The hydrogen ions meet oxide ions that have been created on the cathode side and passed across the electrolyte to the anode side, where they react to create water. A load connected externally between the anode and cathode completes the electrical circuit. Below are the chemical equations for the reaction  Sony VAIO VGN-NR11M/S Battery :

At the anode SOFCs can use nickel or other catalysts to break apart the methanol and create hydrogen ions and carbon monoxide. A solid called yttria stabilized zirconia (YSZ) is used as the electrolyte  Sony VAIO VGN-NR11Z/T Battery .

Like all fuel cell electrolytes YSZ is conductive to certain ions, in this case the oxide ion (O=) allowing passage from the cathode to anode, but is non-conductive to electrons. YSZ is a durable solid and is advantageous in large industrial systems. Although YSZ is a good ion conductor, it only works at very high temperatures  SONY VAIO VGN-FZ180E Battery .

The standard operating temperature is about 950oC. Running the fuel cell at such a high temperature easily breaks down the methane and oxygen into ions. A major disadvantage of the SOFC, as a result of the high heat, is that it “places considerable constraints on the materials which can be used for interconnections”  SONY VAIO VGN-FZ220E Battery .

Another disadvantage of running the cell at such a high temperature is that other unwanted reactions may occur inside the fuel cell. It is common for carbon dust, graphite, to build up on the anode, preventing the fuel from reaching the catalyst. Much research is currently being done to find alternatives to YSZ that will carry ions at a lower temperature SONY VAIO VGN-FZ340E Battery .

MCFC

Molten carbonate fuel cells (MCFCs) operate in a similar manner, except the electrolyte consists of liquid (molten) carbonate, which is a negative ion and an oxidizing agent  SONY VAIO VGN-FZ430E Battery .

Because the electrolyte loses carbonate in the oxidation reaction, the carbonate must be replenished through some means. This is often performed by recirculating the carbon dioxide from the oxidation products into the cathode where it reacts with the incoming air and reforms carbonate  SONY VAIO VGN-FZ460E Battery .

Unlike proton exchange fuel cells, the catalysts in SOFCs and MCFCs are not poisoned by carbon monoxide, due to much higher operating temperatures. Because the oxidation reaction occurs in the anode, direct utilization of the carbon monoxide is possible  SONY VAIO VGN-FZ480E Battery .

Also, steam produced by the oxidation reaction can shift carbon monoxide and steam reform hydrocarbon fuels inside the anode. These reactions can use the same catalysts used for the electrochemical reaction, eliminating the need for an external fuel reformerSONY VAIO VGN-FZ4000 Battery .

MCFC can be used for reducing the CO2 emission from coal fired power plants as well as gas turbine power plants.

High temperature fuel cells

A solid oxide fuel cell (SOFC) is extremely advantageous “because of a possibility of using a wide variety of fuel”  SONY VAIO VGN-FZ31E Battery .

Unlike most other fuel cells which only use hydrogen, SOFCs can run on hydrogen, butane, methanol, and other petroleum products. The different fuels each have their own chemistry  SONY VAIO VGN-FZ31B Battery .

For SOFC methanol fuel cells, on the anode side, a catalyst breaks methanol and water down to form carbon dioxide, hydrogen ions, and free electrons. The hydrogen ions meet oxide ions that have been created on the cathode side and passed across the electrolyte to the anode side, where they react to create water   SONY VAIO VGN-FZ31J Battery .

A load connected externally between the anode and cathode completes the electrical circuit. Below are the chemical equations for the reaction:

At the anode SOFCs can use nickel or other catalysts to break apart the methanol and create hydrogen ions and carbon monoxide  SONY VAIO VGN-FZ31M Battery .

A solid called yttria stabilized zirconia (YSZ) is used as the electrolyte. Like all fuel cell electrolytes YSZ is conductive to certain ions, in this case the oxide ion (O=) allowing passage from the cathode to anode, but is non-conductive to electrons. YSZ is a durable solid and is advantageous in large industrial systems  SONY VAIO VGN-FZ31Z Battery .

Although YSZ is a good ion conductor, it only works at very high temperatures. The standard operating temperature is about 950oC.Running the fuel cell at such a high temperature easily breaks down the methane and oxygen into ions  SONY VAIO VGN-FZ38M Battery .

A major disadvantage of the SOFC, as a result of the high heat, is that it “places considerable constraints on the materials which can be used for interconnections”. Another disadvantage of running the cell at such a high temperature is that other unwanted reactions may occur inside the fuel cell  SONY VGP-BPS8 Battery .

It is common for carbon dust, graphite, to build up on the anode, preventing the fuel from reaching the catalyst. Much research is currently being done to find alternatives to YSZ that will carry ions at a lower temperature  SONY VGP-BPS13/S Battery .

MCFC

Molten carbonate fuel cells (MCFCs) operate in a similar manner, except the electrolyte consists of liquid (molten) carbonate, which is a negative ion and an oxidizing agent   SONY VGP-BPS13A/B Battery .

Because the electrolyte loses carbonate in the oxidation reaction, the carbonate must be replenished through some means. This is often performed by recirculating the carbon dioxide from the oxidation products into the cathode where it reacts with the incoming air and reforms carbonate  SONY VGP-BPS13B/B Battery .

Unlike proton exchange fuel cells, the catalysts in SOFCs and MCFCs are not poisoned by carbon monoxide, due to much higher operating temperatures. Because the oxidation reaction occurs in the anode, direct utilization of the carbon monoxide is possible   SONY VGP-BPS13A/S Battery .

Also, steam produced by the oxidation reaction can shift carbon monoxide and steam reform hydrocarbon fuels inside the anode. These reactions can use the same catalysts used for the electrochemical reaction, eliminating the need for an external fuel reformerSONY VGP-BPS13AS Battery .

MCFC can be used for reducing the CO2 emission from coal fired power plants  as well as gas turbine power plants.

History

The principle of the fuel cell was discovered by German scientist Christian Friedrich Schönbein in 1838 and published in one of the scientific magazines of the time  Dell Inspiron 1320n Battery .

Based on this work, the first fuel cell was demonstrated by Welsh scientist and barrister Sir William Robert Grove in the February 1839 edition of thePhilosophical Magazine and Journal of Science and later sketched, in 1842, in the same journal. The fuel cell he made used similar materials to today'sphosphoric-acid fuel cell Dell Inspiron 1464 Battery .

In 1955, W. Thomas Grubb, a chemist working for the General Electric Company (GE), further modified the original fuel cell design by using a sulphonated polystyrene ion-exchange membrane as the electrolyte   Dell Inspiron 1564 Battery .

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'Dell Inspiron 1764 Battery .

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. It wasn't until 1959 that British engineer Francis Thomas Bacon successfully developed a 5 kW stationary fuel cell  Dell Studio 1450 Battery .

In 1959, a team led by Harry Ihrig built a 15 kW fuel cell tractor for Allis-Chalmers which was demonstrated across the US at state fairs. This system used potassium hydroxide as the electrolyte and compressed hydrogen and oxygen as the reactants  Dell Studio 1457 Battery .

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 )  Dell Latitude D610 Battery .

United Technologies Corporation's UTC Power subsidiary 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    Toshiba NB100 Battery .

UTC Power continues to market this fuel cell as the PureCell 200, a 200 kW system (although soon to be replaced by a 400 kW version, expected for sale in late 2009). UTC Power continues to be the sole supplier of fuel cells to NASA for use in space vehicles, having supplied the Apollo missions  Toshiba Satellite M65 battery ,

and currently the Space Shuttle program, and is developing fuel cells for automobiles, buses, and cell phone towers; the company has demonstrated the first fuel cell capable of starting under freezing conditions with its proton exchange membrane   Toshiba Satellite M60 battery .

Fuel cell efficiency

The efficiency of a fuel cell is dependent on the amount of power drawn from it. Drawing more power means drawing more current, which increases the losses in the fuel cell   Dell Latitude D830 Battery .

As a general rule, the more power (current) drawn, the lower the efficiency. Most losses manifest themselves as a voltage drop in the cell, so the efficiency of a cell is almost proportional to its voltage. For this reason, it is common to show graphs of voltage versus current (so-called polarization curves) for fuel cells  Dell Latitude D620 Battery .

A typical cell running at 0.7 V has an efficiency of about 50%, meaning that 50% of the energy content of the hydrogen is converted into electrical energy; the remaining 50% will be converted into heat. (Depending on the fuel cell system design, some fuel might leave the system unreacted, constituting an additional loss     Dell Inspiron Mini 10 Battery .

For a hydrogen cell operating at standard conditions with no reactant leaks, the efficiency is equal to the cell voltage divided by 1.48 V, based on the enthalpy, or heating value, of the reaction. For the same cell, the second law efficiency is equal to cell voltage divided by 1.23 V  Sony VGN-FW11S Battery .

(This voltage varies with fuel used, and quality and temperature of the cell.) The difference between these numbers represents the difference between the reaction's enthalpy and Gibbs free energy. This difference always appears as heat, along with any losses in electrical conversion efficiency  Sony VGN-FW11M Battery .

Fuel cells are not heat engines and so the Carnot cycle efficiency is not relevant to the thermodynamic efficiency of fuel cells.At times this is misrepresented by saying that fuel cells are exempt from the laws of thermodynamics, because most people think of thermodynamics in terms of combustion processes (enthalpy of formation)  Sony VGN-FW139E/H battery .

The laws of thermodynamics also hold for chemical processes (Gibbs free energy) like fuel cells, but the maximum theoretical efficiency is higher (83% efficient at 298K  in the case of hydrogen/oxygen reaction) than the Otto cycle thermal efficiency (60% for compression ratio of 10 and specific heat ratio of 1.4) Dell Latitude E5400 Battery .

Comparing limits imposed by thermodynamics is not a good predictor of practically achievable efficiencies. Also, if propulsion is the goal, electrical output of the fuel cell has to still be converted into mechanical power with another efficiency drop  Dell Latitude E4200 Battery .

In reference to the exemption claim, the correct claim is that "limitations imposed by the second law of thermodynamics on the operation of fuel cells are much less severe than the limitations imposed on conventional energy conversion systems"  Dell Inspiron 300M Battery .

Consequently, they can have very high efficiencies in converting chemical energy to electrical energy, especially when they are operated at low power density, and using pure hydrogen and oxygen as reactants  Dell Vostro A840 Battery .

It should be underlined that fuel cell (especially high temperature) can be used as a heat source in conventional heat engine (gas turbine system). In this case the ultra high efficiency is predicted (above 70%)    Dell Studio 1737 battery .

In practice

For a fuel cell operating on air, losses due to the air supply system must also be taken into account. This refers to the pressurization of the air and dehumidifying it   Dell Inspiron E1505 battery .

This reduces the efficiency significantly and brings it near to that of a compression ignition engine. Furthermore, fuel cell efficiency decreases as load increases.

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  Dell RM791 battery .

The comparable NEDC value for a Diesel vehicle is 22%. In 2008 Honda released a fuel cell electric vehicle (the Honda FCX Clarity) with fuel stack claiming a 60% tank-to-wheel efficiency  Dell XPS M1530 battery .

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  Dell XPS M2010 battery .

In addition to the production losses, over 70% of US' electricity used for hydrogen production comes fromthermal power, which only has an efficiency of 33% to 48%, resulting in a net increase in carbon dioxide production by using hydrogen in vehicles . However, more than 90% of all hydrogen is produced by steam methane reforming  Acer Aspire One battery .

Fuel cells cannot store energy like a battery, but in some applications, such as stand-alone power plants based on discontinuous sources such as solar or wind power, they are combined withelectrolyzers and storage systems to form an energy storage systemToshiba Satellite P10 Battery .

The overall efficiency (electricity to hydrogen and back to electricity) of such plants  is between 30 and 50%, depending on 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  SONY VGN-FZ210CE Battery .

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  Dell Precision M70 Battery .

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  Toshiba Satellite L305 Battery .

Power

Fuel cells are very useful as power sources in remote locations, such as spacecraft, remote weather stations, large parks, rural locations, and in certain military applications. A fuel cell system running on hydrogen can be compact and lightweight, and have no major moving parts   Toshiba Satellite T4900 Battery .

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 around one minute of down time in a two year period  Toshiba PA3399U-2BRS battery .

Since 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. In this application, batteries would have to be largely oversized to meet the storage demand, but fuel cells only need a larger storage unit Toshiba Satellite A200 Battery .

One such pilot program is operating on Stuart Island in Washington State. There the Stuart Island Energy Initiative has built a complete, closed-loop system: Solar panels power an electrolyzer which makes hydrogen. The hydrogen is stored in a 500 gallon tank at 200 PSI, and runs a ReliOn fuel cell to provide full electric back-up to the off-the-grid residence Toshiba Satellite 1200 Battery.

Cogeneration

Micro combined heat and power (MicroCHP) systems such as home fuel cells and cogeneration for office buildings and factories are in the mass production phase     Toshiba Satellite M300 Battery .

The system generates constant electric power (selling excess power back to the grid when it is not consumed), and at the same time produces hot air and water from the waste heat. MicroCHP is usually less than 5 kWe for a home fuel cell or small business  SONY VGP-BPS13A/Q Battery .

A lower fuel-to-electricity conversion efficiency is tolerated (typically 15-20%), because most of the energy not converted into electricity is utilized as heat. Some heat is lost with the exhaust gas just as in a normal furnace, so the combined heat and power efficiency is still lower than 100%, typically around 80%  SONY VGP-BPS13A/Q Battery .

In terms of exergy however, the process is inefficient, and one could do better by maximizing the electricity generated and then using the electricity to drive a heat pump. Phosphoric-acid fuel cells (PAFC) comprise the largest segment of existing CHP products worldwide and can provide combined efficiencies close to 90%  SONY VGP-BPS13B/Q Battery

(35-50% electric + remainder as thermal) Molten-carbonate fuel cells have also been installed in these applications, andsolid-oxide fuel cell prototypes exist.

Hydrogen transportation and refueling

In 2003 President George Bush proposed the Hydrogen Fuel Initiative (HFI), which was later implemented by legislation through the 2005 Energy Policy Act and the 2006 Advanced Energy Initiative  SONY VGP-BPS13B/Q Battery .

These aimed at further developing hydrogen fuel cells and its infrastructure technologies with the ultimate goal to produce commercial fuel cell vehicles by 2020. By 2008, the U.S. had contributed 1 billion dollars to this project  SONY VGP-BPS13/Q Battery .

In May 2009, however, the Obama Administration announced that it will "cut off funds" for the development of fuel cell hydrogen vehicles, since other vehicle technologies will lead to quicker reduction in emissions in a shorter time  SONY VGP-BPS13/Q Battery .

The US Secretary of Energy explained that hydrogen vehicles "will not be practical over the next 10 to 20 years", and also mentioned the challenges involved in the development of the required infrastructure to distribute hydrogen fuel. Nevertheless, the U.S  SONY VGP-BPS21A/B Battery .

government will continue to fund research related to stationary fuel cells. The National Hydrogen Associationand the U.S. Fuel Cell Council criticized this decision arguing that "...the cuts proposed in the DOE hydrogen and fuel cell program threaten to disrupt commercialization of a family of technologies that are showing exceptional promise and beginning to gain market traction SONY VGP-BPS21/S Battery ."

There are numerous prototype or production cars and buses based on fuel cell technology being researched or manufactured by motor car manufacturers  SONY VGP-BPS21B Battery .

The GM 1966 Electrovan was the automotive industry's first attempt at an automobile powered by a hydrogen fuel cell. The Electrovan, which weighed more than twice as much as a normal van, could travel up to 70 mph for 30 seconds  SONY VGP-BPS21A Battery .

The 2001 Chrysler Natrium used its own on-board hydrogen processor. It produces hydrogen for the fuel cell by reacting sodium borohydride fuel with Borax, both of which Chrysler claimed were naturally occurring in great quantity in the United States  SONY VGP-BPS21 Battery .

The hydrogen produces electric power in the fuel cell for near-silent operation and a range of 300 miles without impinging on passenger space. Chrysler also developed vehicles which separated hydrogen from gasoline in the vehicle, the purpose being to reduce emissions without relying on a nonexistent hydrogen infrastructure and to avoid large storage tanks Sony VGP-BPS21A/B Battery .

In 2005 the British firm Intelligent Energy produced the first ever working hydrogen run motorcycle called the ENV (Emission Neutral Vehicle). The motorcycle holds enough fuel to run for four hours, and to travel 100 miles in an urban area, at a top speed of 50 miles per hour  Sony VGP-BPS21/S Battery .

In 2004 Honda developed a fuel-cell motorcycle which utilized the Honda FC Stack.

In 2007, the Revolve Eco-Rally (launched by HRH Prince of Wales) demonstrated several fuel cell vehicles on British roads for the first time, driven by celebrities and dignitaries from Brighton to London's Trafalgar Square  Sony VGP-BPS21A Battery .

Fuel cell powered race vehicles, designed and built by university students from around the world, competed in the world's first hydrogen race series called the 2008 Formula Zero Championship, which began on August 22, 2008 in Rotterdam, the Netherlands. More races are planned for 2009 and 2010  Sony VGP-BPS21 Battery .

After this first race, Greenchoice Forze from the university of Delft (The Netherlands) became leader in the competition. Other competing teams are Element One (Detroit), HerUCLAs (LA), EUPLAtecH2 (Spain), Imperial Racing Green (London) and Zero Emission Racing Team (Leuven) Sony Vaio PCG-5G2L Battery .

In 2008, Honda released a hydrogen vehicle, the FCX Clarity. Meanwhile there exist also other examples of bikes  and bicycles  with a hydrogen fuel cell engine.

A few companies are conducting hydrogen fuel cell research and practical fuel cell bus trials  Sony Vaio PCG-5G3L Battery .

Daimler AG, with thirty-six experimental units powered byBallard Power Systems fuel cells completing a successful three-year trial, in eleven cities, in January 2007.  There are also fuel cell powered buses currently active or in production, such as a fleet of Thor buses with UTC Power fuel cells in California, operated by SunLine Transit Agency Sony Vaio PCG-5J1L Battery .

The Fuel Cell Bus Club is a global cooperative effort in trial fuel cell buses.

The first Brazilian hydrogen fuel cell bus prototype will begin operation in São Paulo during the first semester of 2009 Sony Vaio PCG-5K2L Battery .

The hydrogen bus was manufactured inCaxias do Sul and the hydrogen fuel will be produced in São Bernardo do Campo from water through electrolysis . The program, called "Ônibus Brasileiro a Hidrogênio" (Brazilian Hydrogen Autobus), includes three additional buses  Sony Vaio PCG-5J2L Battery .

Airplanes

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   Sony Vaio PCG-5K1L Battery .

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  Sony Vaio PCG-6S2L Battery .

The fuel cell was a unique FlatStackTM stack design which allowed the fuel cell to be integrated with the aerodynamic surfaces of the plane.

Boats

The world's first Fuel Cell Boat HYDRA used an AFC system with 6.5 kW net output Sony Vaio PCG-6S3L Battery .

Submarines

The Type 212 submarines of the German and Italian navies use fuel cells to remain submerged for weeks without the need to surface.

Fueling stations

The first public hydrogen refueling station was opened in Reykjavík, Iceland in April 2003  Sony Vaio PCG-6V1L Battery .

This station serves three buses built by DaimlerChrysler that are in service in the public transport net of Reykjavík. The station produces the hydrogen it needs by itself, with an electrolyzing unit (produced by Norsk Hydro), and does not need refilling: all that enters is electricity and water  Sony Vaio PCG-6W1L Battery .

Royal Dutch Shell is also a partner in the project. The station has no roof, in order to allow any leaked hydrogen to escape to the atmosphere.

The California Hydrogen Highway is an initiative by the California Governor to implement a series of hydrogen refueling stations along that state  Sony Vaio PCG-6W2L Battery .

These stations are used to refuel hydrogen vehicles such as fuel cell vehicles and hydrogen combustion vehicles. As of July 2007 California had 179 fuel cell vehicles and twenty five stations in operation,and ten more stations have been planned for assembly in California  Sony Vaio PCG-6W3L Battery .

However, there have already been three hydrogen fueling stations decommissioned.

South Carolina also has a hydrogen freeway in the works. There are currently two hydrogen fueling stations, both in Aiken and Columbia, SC  Sony Vaio PCG-7111L Battery .

Additional stations are expected in places around South Carolina such as Charleston, Myrtle Beach, Greenville, and Florence. According to the South Carolina Hydrogen & Fuel Cell Alliance, the Columbia station has a current capacity of 120 kg a day, with future plans to develop on-site hydrogen production from electrolysis and reformation Sony Vaio PCG-7112L Battery .

The Aiken station has a current capacity of 80 kg. There is extensive funding for Hydrogen fuel cell research and infrastructure in South Carolina. The University of South Carolina, a founding member of the South Carolina Hydrogen & Fuel Cell Alliance, received 12.5 million dollars from the United States Department of Energy for its Future Fuels Program Sony Vaio PCG-7113L Battery .

Japan also has a hydrogen highway, as part of the Japan hydrogen fuel cell project. Twelve hydrogen fueling stations have been built in 11 cities in Japan.Canada, Sweden and Norway also have hydrogen highways implemented  Sony Vaio PCG-7133L Battery .

Other applications

  • Providing power for base stations or cell sites
  • Off-grid power supply  Sony Vaio PCG-7Z2L Battery
  • Distributed generation
  • Fork Lifts  Sony Vaio PCG-8Y1L Battery
  • Emergency power systems are a type of fuel cell system, which may include lighting, generators and other apparatus, to provide backup resources in a crisis or when regular systems fail  Sony Vaio PCG-8Y2L Battery .
  • They find uses in a wide variety of settings from residential homes to hospitals, scientific laboratories, data centers,telecommunication  equipment and modern naval ships  Sony Vaio PCG-8Z1L Battery .
  • An uninterrupted power supply (UPS) provides emergency power and, depending on the topology, provide line regulation as well to connected equipment by supplying power from a separate source when utility power is not available. Unlike a standby generator, it can provide instant protection from a momentary power interruption Sony Vaio PCG-8Z2L Battery .
  • Base load power plants
  • Electric and hybrid vehicles.
  • Notebook computers for applications where AC charging may not be available for weeks at a time.
  • Portable charging docks for small electronics (e.g. a belt clip that charges your cell phone or PDA)  SONY VAIO VGN-FW31J Battery .
  • Smartphones with high power consumption due to large displays and additional features like GPS might be equipped with micro fuel cells.
  • Small heating appliances
  • Space Shuttles  SONY VAIO VGN-FW31E Battery

Market structure

Not all geographic markets are ready for SOFC powered m-CHP appliances. Currently, the regions that lead the race in Distributed Generation and deployment of fuel cell m-CHP units are the EU and Japan  SONY VAIO VGN-FW31B Battery .
Fuel cell economics

Use of hydrogen to fuel vehicles would be a critical feature of a hydrogen economy. A fuel cell and electric motor combination is not directly limited by the Carnot efficiency of an internal combustion engine  SONY VAIO VGN-FW31M Battery .

Low temperature fuel cell stacks proton exchange membrane fuel cell (PEMFC), direct methanol fuel cell (DMFC) and phosphoric acid fuel cell (PAFC) use a platinum catalyst. Impurities createcatalyst poisoning (reducing activity and efficiency) in these low-temperature fuel cells, thus high hydrogen purity or higher catalyst densities are required  SONY VAIO VGN-FW31Z Battery .

Although there are sufficient platinum resources for future demand,  most predictions of platinum running out and/or platinum prices soaring do not take into account effects of reduction in catalyst loading and recycling   SONY VAIO VGN-FW38M Battery .

Recent research at Brookhaven National Laboratory could lead to the replacement of platinum by a gold-palladium coating which may be less susceptible to poisoning and thereby improve fuel cell lifetime considerably.Another method would use iron and sulphur instead of platinum   SONY VAIO VGN-AW41JF Battery .

This is possible through an intermediate conversion by bacteria. This would lower the cost of a fuel cell substantially (as the platinum in a regular fuel cell costs around $1500, and the same amount of iron costs only around $1.50). The concept is being developed by a coalition of the John Innes Centre and theUniversity of Milan-Bicocca  SONY VAIO VGN-AW41JF/H Battery .

PEDOT cathodes are immune to monoxide poisoning.

Current targets for a transport PEM fuel cells are 0.2 g/kW Pt – which is a factor of 5 decrease over current loadings – and recent comments from major original equipment manufacturers (OEMs) indicate that this is possible  SONY VAIO VGN-AW41MF Battery .

Recycling of fuel cells components, including platinum, will conserve supplies. High-temperature fuel cells, including molten carbonate fuel cells (MCFC's) and solid oxide fuel cells (SOFC's), do not use platinum as catalysts, but instead use cheaper materials such as nickel and nickel oxide  SONY VAIO VGN-AW41MF/H Battery .

They also do not experience catalyst poisoning by carbon monoxide, and so they do not require high-purity hydrogen to operate. They can use fuels with an existing and extensive infrastructure, such as natural gas, directly, without having to first reform it externally to hydrogen and CO followed by CO removal  SONY VAIO VGN-FW30B Battery .

Research and development

  • August 2005: Georgia Institute of Technology researchers use triazole to raise the operating temperature of PEM fuel cells from below 100 °C to over 125 °C, claiming this will require less carbon-monoxide purification of the hydrogen fuel  SONY VAIO VGN-FW50B Battery .
  • 2008 Monash University, Melbourne uses PEDOT as a cathode.
  • 2009 Researchers at the University of Dayton, in Ohio, have shown that arrays of vertically grown carbon nanotubes could be used as the catalyst in fuel cells  SONY VAIO VGN-FW51B/W Battery .
  • 2009: Y-Carbon has begun to develop a carbide-derived-carbon-based ultracapacitor with high energy density which may lead to improvements in fuel cell technology.
  • 2009: A nickel bisdiphosphine-based catalyst for fuel cells is demonstrated  SONY VAIO VGN-FW51MF Battery .

The Fuel Cell Development Information Center (FCDIC) is a Japanese center established in July 1986 to exchange information among its members on fuel cell research, development and deployment to speed up the introduction and penetration of fuel cells into the market  SONY VAIO VGN-FW51MF/H Battery .

The FCDIC consists of 154 organizations, 40 academic individuals, and 3 foreign members. The organisation publishes the quarterly journal The Journal of Fuel Cell Technology and the latest fuel cell news in Japan SONY VAIO VGN-FW51ZF Battery

The European Fuel Cells and Hydrogen Joint Technology Initiative is a public-private venture to "deliver 'fit-for-use' hydrogen energy and fuel celltechnologies developed to the point of commercial take-off " SONY VAIO VGN-FW51ZF/H Battery .

The Fuel Cells and Hydrogen Joint Technology Initiative is a component of the Joint Technology Initiatives of the Seventh Framework Programme of the European Commission SONY VAIO VGN-FW52JB Battery .

History

In May 2003, a European Commission High Level Group presented a report on "Hydrogen Energy and Fuel Cells — a vision of our future" that recommended the formation of a technology partnership between the Commission and private enterprise for the development of hydrogen and fuel cell technologies SONY VAIO VGN-FW54FB Battery .

The report also recommended the establishment of a pilot programme, with European Commission funding, to make hydrogen and fuel cell technologies commercially viable SONY VAIO VGN-FW70DB Battery .

In November of the same year, the EC adopted its "European Initiative for Growth" program that established a Hydrogen economy quick-start project with a budget of 2.8 billion Euros for the decade 2004 through 2015  SONY VAIO VGN-FW71DB/W Battery .

The initiative allowed for possible funding from structural funds and from the EC's 'Research, Technological development and Demonstration Framework Programmes'. The initiative placed an emphasis on long-term research and cooperation with advisory boards  SONY VAIO VGN-FW72JGB Battery .

In December 2003, the Commission facilitated the establishment of a 'European Hydrogen and Fuel Cell Technology Platform' that sought to bring together interested partners in a joint venture that would further what the High Level Group had envisioned seven months earlier SONY VAIO VGN-FW73JGB Battery .

In March 2005, the 'European Hydrogen and Fuel Cell Technology Platform' adopted a research agenda for accelerating the development and market introduction of fuel cell and hydrogen technologies within the European Community. This agenda called for funding by the EC and organisations from the public- and private sectors SONY VAIO VGN-FW74FB Battery .

On 19 December 2006, the agenda of the Technology Platform were adopted by the Council Decision 2006/975/EC within the EC's Seventh Framework Programme. The prospect of further financing from the European Investment Bank (in particular through its Risk-Sharing Finance Facility) had been established in an earlier decision (2006/971/EC) SONY VAIO VGN-FW81HS Battery .

In March 2007 the European Council concluded that the Union's member states had an interest in taking a lead position in renewable energy programs. On 10 October 2007, the European Commission adopted two proposals to further the development and marketing of clean and safe hydrogen vehicles   SONY VAIO VGN-FW81NS Battery.

One proposal was to simplify the regulatory procedures for hydrogen-powered vehicles. The other proposal was the establishment up of the 'Fuel Cells and Hydrogen Joint Technology Initiative' as called for by the Hydrogen and Fuel Cell Technology Platform  SONY VAIO VGN-FW81S Battery .

The Commission's second proposal was duly considered by the European Parliament and the Council of Ministers, and on 30 May 2008 the Council passed regulation number 521/2008 setting up the "Fuel Cells and Hydrogen Joint Undertaking" that will run until 31 December 2017  SONY VAIO VGN-FW82DS Battery.

Article 2 of the regulation stipulated a contribution to the implementation of the Seventh Framework Programme, in particular to its energy-, nanotechnologies-, environment-, and transport-specific programmes. The "Joint Technology Initiative on Fuel Cells and Hydrogen"  SONY VAIO VGN-FW82JS Battery .

would accordingly receive appropriations in the general budget of the European Union allocated to those programmes. Article 5 established a maximum community contribution cap of € 470 million. The objectives of the fuel cell initiative were to be pursued by pooling resources from the public and private sectors   SONY VAIO VGN-FW82XS Battery

The 'Fuel Cells and Hydrogen Joint Technology Initiative' was launched on 14 October 2008  during the General Assembly of Fuel Cells and Hydrogen Stakeholders  SONY VAIO VGN-FW83DS Battery .

A press release from the European Hydrogen and Fuel Cell Technology Platform reiterates an estimate "that the activities of the JTI will reduce time to market for hydrogen and fuel cell technologies by between 2 and 5 years  SONY VAIO VGN-FW83JS Battery ."

Membership and structure

The public-private joint initiative operates under the auspices of the DG Research of the European Commission, representing the European Communities, and industry.  SONY VAIO VGN-FW83XS Battery

Governance of the 'Fuel Cells and Hydrogen Joint Technology Initiative' (FCH JTI) lies with the 'Fuel Cells and Hydrogen Joint Undertaking'. Members of that body are the European Community and the 'JTI Industry Grouping' 

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