A TECHNICAL SEMINAR REPORT ON “HYDROGEN VEHICLE” Submitted in partial fulfillment of the requirement for the award of degree of BACHELOR OF TECHNOLOGY IN ELECTRONICS & COMMUNICATION ENGINEERING (Jawaharlal Nehru Technological University Hyderabad) Submitted by B. SANTHOSH KUMAR (08791A0484) Under The Esteemed Guidance Of J. SRIDHAR Asst. Prof
DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING AIZZA COLLEGE OF ENGINEERING AND TECHNOLOGY (Affiliated to JNTUH, Hyderabad) Mulkalla, Mancherial, Adilabad - 504 209
DEPARTMENT OF ELECTRONICS & COMMUNICATION ENGINEERING (AIZZA COLLEGE OF ENGINEERING AND TECHNOLOGY) MULKALLA, MANCHERIAL, ADILABAD-504209 CERTIFICATE
This is to certify that the technical semina seminarr report report on “HYDROGEN VEHICLE”
Submitted
by
B.
SANTHOSH KUMAR
partiall fulfil fulfillme lment nt for the requir requireme ement nt of the degree degree of Bachel Bachelor or of (08791A0484) in the partia Technology. JNTUH, Hyderabad. This is a technical seminar report in the academic session 2011-2012.
INTERNAL GUIDE
H.O.D
E.C.E
E.C.E
PRINCIPAL AZCET
ACKNOWLEDGEMENT
DEPARTMENT OF ELECTRONICS & COMMUNICATION ENGINEERING (AIZZA COLLEGE OF ENGINEERING AND TECHNOLOGY) MULKALLA, MANCHERIAL, ADILABAD-504209 CERTIFICATE
This is to certify that the technical semina seminarr report report on “HYDROGEN VEHICLE”
Submitted
by
B.
SANTHOSH KUMAR
partiall fulfil fulfillme lment nt for the requir requireme ement nt of the degree degree of Bachel Bachelor or of (08791A0484) in the partia Technology. JNTUH, Hyderabad. This is a technical seminar report in the academic session 2011-2012.
INTERNAL GUIDE
H.O.D
E.C.E
E.C.E
PRINCIPAL AZCET
ACKNOWLEDGEMENT
I would express our sincere gratitude to all those who have guided us in successfully accomplishing my technical seminar report.
I would specially thank my internal guide J. SRIDHAR Asst. Prof. He explained the main aim of the technical seminar report. I’m grateful to his for having shared his knowledge and for putting putting forth forth his encourage encouragemen ment, t, support support and valuab valuable le guidel guideline iness in the course course of our technical seminar report.
I exte extend nd hear hearti ties estt than thanks ks to our our Head Head of the the Depa Depart rtme ment nt of Elec Electr tron onic icss and and Communication Engineering Mr. P.PRABHAKAR Assoc. Prof . who had been a constant source of inspiration to us for his motivations in making this technical seminar report.
I prof profus usel ely y than thank k our our PRIN his PRINCIP CIPAL AL Dr. Dr. M. TH THIR IRUP UPAT ATHI HI REDD REDDY Y for his encouragement and support. More over I sincerely thankful for giving me an opportunity to present this technical seminar report.
Lastly we express heart full thanks to all our faculty and friends for their constant support, encouragement and valuable contribution in completion of the technical seminar report.
B. SANTHOSH KUMAR (08791A0484)
Contents
1. Introduction 2. Internal combustion vehicle 3. Design and how it works 4. Specifications for the system 5. Hydrogen storage and safety 6. Fuel cell 7. Hydrogen 7.1 Production 7.2 Storage 7.3 Infrastructure 7.4 Codes and standards 8. Criticism 9. Comparison with other types of alternative fuel vehicle 9.1 Plug-in hybrids 9.2 Natural gas 9.3 Battery electric vehicles 10. Hydrogen economy 10.1 Fuel cell cost and durability 10.2 Hydrogen production and delivery 10.3 Public acceptance
11. Applications 12. Advantages 13. Disadvantages 14. Future scope 15. References
1. INTRODUCTION: A hydrogen vehicle is a vehicle that uses hydrogen as its onboard fuel for motive power. Hydrogen vehicles include hydrogen fueled space rockets, as well as automobiles and other transportation vehicles. The power plants of such vehicles convert the chemical energy of hydrogen to mechanical energy either by burning hydrogen in an internal combustion engine, or by reacting hydrogen with oxygen in a fuel cell to run electric motors. Widespread use of hydrogen for fueling transportation is a key element of a proposed hydrogen economy. Hydrogen fuel does not occur naturally on Earth and thus is not an energy source, but is an energy carrier. Currently it is most frequently made from methane or other fossil fuels. However, it can be produced from a wide range of sources (such as wind, solar, or nuclear) that are intermittent, too diffuse or too cumbersome to directly propel vehicles. Integrated wind-tohydrogen plants, using electrolysis of water , are exploring technologies to deliver costs low enough, and quantities great enough, to compete with traditional energy sources.[1] Many companies are working to develop technologies that might efficiently exploit the potential of hydrogen energy for mobile uses. The attraction of using hydrogen as an energy currency is that, if hydrogen is prepared without using fossil fuel inputs, vehicle propulsion would not contribute to carbon dioxide emissions. The drawbacks of hydrogen use are low
energy content per unit volume, high tankage weights, very high storage vessel pressures, the storage, transportation and filling of gaseous or liquid hydrogen in vehicles, the large investment in infrastructure that would be required to fuel vehicles, and the inefficiency of production processes.
2 INTERNAL COMBUSTION VEHICLE :
Hydrogen internal combustion engine cars are different from hydrogen fuel cell cars. The hydrogen internal combustion car is a slightly modified version of the traditional gasoline internal combustion engine car. These hydrogen engines burn fuel in the same manner that gasoline engines do. Francois Isaac de Rivaz designed in 1807 the first hydrogen-fueled internal combustion engine. Paul Dieges patented in 1970 a modification to internal combustion engines which allowed a gasoline-powered engine to run on hydrogen US 3844262. Mazda has developed Wankel engines burning hydrogen. The advantage of using ICE (internal combustion engine) like Wankel and piston engines is the cost of retooling for production I much lower. Existing-technology ICE can still be applied for solving those problems where fuel cells are not a viable solution insofar, for example in cold-weather applications. 3. DESIGN AND HOW IT WORKS: Final Concept Design
This
section
gives
an
overview
of
some
of the
technologies
incorporated in the design of the Station, and provides a basis for the understanding of the components’ operation. Specific equipment used in the Station is also identified. The Station operates as follows: • Electricity is produced by the diesel generator and distributed to the Stations equipment through the Service Entrance Panel. • Water is held in the onboard water supply tank, and is gravity-fed to the hydrogen generator. • The hydrogen generator uses the electricity and water to produce hydrogen via electrolysis. • The chiller pumps coolant to cool the compressor. • High-pressure hydrogen is pumped from the compressor to storage tanks where it is ready to be dispensed when needed.
The Station
The power plants of such vehicles convert the chemical energy of hydrogen to mechanical energy either by burning hydrogen in an internal combustion engine, or by reacting
hydrogen with oxygen in a fuel cell to run electric motors. Widespread use of hydrogen for fueling transportation is a key element of a proposed hydrogen economy.
3.1 Infrastructure The hydrogen infrastructure consists mainly of industrial hydrogen pipeline transport and hydrogen-equipped filling stations like those found on a hydrogen highway. Hydrogen stations which are not situated near a hydrogen pipeline can obtain supply via hydrogen tanks, compressed hydrogen tube trailers, liquid hydrogen tank trucks or dedicated onsite production. Hydrogen use would require the alteration of industry and transport on a scale never seen before in history. For example, according to GM, 70% of the U.S. population lives near a hydrogen-generating facility but has little access to hydrogen, despite its wide availability for commercial use.[60] The distribution of hydrogen fuel for vehicles throughout the U.S. would require new hydrogen stations costing, by some estimates, 20 billion dollars.[61] and 4.6 billion in the EU.[62] Other estimates place the cost as high as half trillion dollars in the United States alone.
4. SPECIFICATIONS FOR THE SYSTEM: 4.1 Electrical Power Source When most people think of electrical power use they relate to their home electric utility bill. Energy consumption, measured in kilowatt-hours (kWh), is charged at a given rate to determine the total. In order to determine an average demand (kW), the total consumption can be divided by the number of hours in the billing period. For example, an average home may consume 720 kWh in a 30 day period. 720 kWh / ( 30 days *24 hrs / day) = 1kW Further, knowing that Amps = Watts/Volts, the service requirements can be found by simply dividing by the supply voltage, typically 240 V for residential service. 1000 W / 240 V = 4.2 A
Yet most homes have a 200 A service from their utility supplier. The discrepancy lies in the definition of average power consumption. The average power consumption is the integration of the instantaneous energy demand over a given time period. The instantaneous consumption may often be near zero, such as a mild spring day when no one is home and the only thing using electricity is the digital clock on the night stand. Contrast this to a cold winter night when the electric water heater has both of its 4000 W elements energized to heat the tank after the dishwasher has run, the electric clothes dryer is operating along with the 15 kW of strip heat in the heat pump, and nearly every light is on in the house. This condition may only occur for a few minutes each year but the electrical system must be robust enough to handle power demanded during this time.
The Station faces a similar situation with the added complexity of the ability to start motor loads without voltage sags which may cause components to cycle off and on. Motors can draw several times their rated name plate values for short durations which could potentially cause severe voltage sags if the system is not designed properly. Therefore, when selecting the power source for the Station, it was vital to select a diesel powered generator capable of providing sufficient electricity.
It was determined that the total run load of the components would be about 33 kVA. Adding the total startup loads if all equipment in the Station was started simultaneously would significantly increase the total load. However, it is assumed that not all equipment would be started up at the same time, as the water purifier would be started first, followed by the electrolyzer, the compressor, and then the chiller. It was calculated that a 50 kW diesel generator will provide sufficient power to operate all the components.
The 50 kW Generac Model SD050 diesel generator was selected for the Station. The generator is shown in Figure 2. 4 At maximum power for continuous use it supplies 40 kW. It generates 120/240 Volts at a frequency of 60 Hertz, and during continuous use supplies more than enough power to run all components simultaneously. The dimensions of the generator are 93 x 40 x 55 inches, and it weighs 2900 pounds.
Figure 2: General 50 kW Diesel Generator5
4.2 Electrical Interface
When dealing with electricity, the most important issue is safety. To control electrical flow and prevent overloading, Load Panels are used. These panels are commonly known as breaker panels, switch boxes, or fuse boxes. They act as a type of traffic controller for an electrical application. The Station will employ a panel similar to that used for commercial applications, rather than residential, in that the panel will be a 3-phase 240/120 panel. Rather than receiving electricity from utility lines, however, it will receive electricity from the Station’s diesel generator. From the panel, electricity will be routed to each of the Station’s components. If the Station is used in locations where utility service is available, it will be possible to supply electricity from the grid. A service pole can be installed, and wired
into the Stations panel, bringing electricity to the Station similar to the way it would be supplied to a residence.
4.3Water Supply
The Station will require a constant supply of water for the operation of the hydrogen generator. The Station is designed to be used in remote locations, so an onboard water storage tank will be used. The tank will be fabricated onto an interior wall of the Station’s container. Its dimensions and construction are discussed in the Installation and Specification section. The electrolyzer, which receives water from the purifier, requires 5.6 gallons/day to operate. The 144 gallon water tank will provide sufficient water to operate the Station for approximately 25 days at full load without refilling the tank. 4.4 Water Purifier:
The operation of the hydrogen electrolysis generator requires ASTM Type II de-ionized (DI) water. That is, water having greater than 1 megohmcm resistivity. Water is deionized by removing ions, such as cations from sodium, calcium, iron, copper and anions such as chloride and bromide. The process removes all ions except H 3O+ and OH−, but it may still contain other non-ionic types of impurities such as organic compounds that will also need to be filtered.
4.5 Hydrogen Generator
The Hogen RE 40 hydrogen generator was selected for use in the Station. It produces hydrogen from water and electricity by means of Proton Exchange Membrane (PEM) electrolysis, which is just the reverse of a PEM fuel cell process. The Hogen generator produces 99.999+% pure hydrogen gas on demand.
Deionized water is introduced into the system where water is split into oxygen, protons, and electrons on one electrode (anode) by applying a DC voltage higher than a thermoneutral voltage (1.482 V).
4.6 Hydrogen Compressor
In order to move hydrogen from the electrolyzer into the vehicle being fueled, a pressure difference must exist. The electrolyzer produces hydrogen at approximately 200 psi, and hydrogen-fueled vehicles will require a pressure of around 5000 psi to fill their tanks. Therefore, the hydrogen must be compressed prior to the fueling process.
The Station uses a high pressure storage process to produce sufficient volume and pressure. After hydrogen is generated by the electrolyzer, it is stored at 200 psi in a low pressure accumulator tank. It is then fed to the compressor where it is compressed to a greater pressure than that required for fueling, and is discharged to the high pressure storage tanks. Figure 7 shows a diagram of the process. Note that this diagram also shows an optional accumulator tank. This tank may be used in applications where the compressor requires greater flow rate than the hydrogen generator can produce.
Figure 8:
4.7 Chiller
Inefficiencies in the operation of the compressor require that the excess heat be removed from this device. For equipment in the size range considered for the Station, chilled water systems are often chosen over chilled air devices. The chiller consists of a refrigeration unit and a closed coolant loop. The chiller’s refrigeration unit is a closed-loop system that compresses its refrigerant gas, which is then passed through the condenser where it is cooled and condensed into liquid. The liquefied refrigerant is then passed through a throttling device that lowers the pressure.
4.8 External Hydrogen Storage and Supply
One of the challenges faced when producing hydrogen is storage. Whether the application is hydrogen-fueled vehicles or large scale hydrogen production, it is vital to have safe, reliable storage capabilities that will not fail prematurely over time. Hydrogen is produced for the Station by a Hogen RE 40 electrolyzer at 200 psig and a rate of 44 SCFH.14 However, a vehicle being refueled would require pressure of approximately 5000 psig in order to approach its maximum capacity. Further, a flow rate of 40 SCFH would create a very slow refilling process.
4.9 Uninterruptible Power Supply
The Station’s safety system incorporates an uninterruptible power supply (UPS) to maintain operation of vital safety equipment during a generator power failure. The power failure may be a result of generator failure or emergency shutdown. When an emergency stop or hydrogen sensor is triggered, the circuit disables the Hogen, the chiller, and the compressor. The UPS will maintain power to the emergency lights, ventilation fan, and safety shutdown system, including hydrogen sensors and emergency power stops.
5. HYDROGEN FUEL STORAGE SAFETY
Hydrogen has a reputation for being explosive and therefore raises concerns about the safety of carrying a substantial quantity of H2 in a vehicle fuel tank. However, because H2 is the lightest gas, it has a tendency to diffuse away quickly in case its container is breached and consequently may represent less of a hazard than gasoline. The simplest way to carry hydrogen fuel in a car or other vehicle is as a high-pressure gas 3-10 kpsi (21-69 MPa) in metal or composite-reinforced (fiberglass, carbon fiber, Kevlar) tanks. This is similar to the way compressed natural gas (CNG) vehicles operate.
There is an interesting report on H2 for energy use [43] by the Norwegian environmental organization Bellona with useful safety information in Chapter 5. These authors conclude that .hydrogen is no more or less dangerous than any other energy carrier and furthermore that hydrogen has properties that in certain areas make it safer than other energy carriers: it is not poisonous, and has the ability to dissipate quickly into the atmosphere because of its light weight compared to air.
6. FUEL CELL: While fuel cells themselves are potentially highly energy efficient, and working prototypes were made by Francis Thomas Bacon in 1959[32] and Roger E. Billings in the 1960s, at least four technical obstacles and other political considerations exist regarding the development and use of a fuel cell-powered hydrogen car: the cost, reliability and durability of the fuel cells; storage of hydrogen for use in fuel cells; production of hydrogen; and delivery of hydrogen to vehicles.[33] 6.1 Fuel cell cost: Currently, hydrogen fuel cells are relatively expensive to produce and some are fragile. As of October 2009, Fortune magazine estimated the cost of producing the Honda Clarity at $300,000 per car.[34] Also, many designs require rare substances such as platinum as a catalyst in order to work properly. Occasionally, a catalyst can become contaminated by impurities in the hydrogen supply, rendering the fuel cell inoperable. In 2010, research and design advances developed a new nickel-tin nanometal catalyst which lowers the cost of cells.[35] Fuel cells are generally priced in USD/kW. The U.S. Department of Energy estimated that the cost of a fuel cell for an automobile in 2002 was approximately $275/kw, which translated into each vehicle costing more than 1 million dollars. However, by 2010, the Department of Energy estimated that the cost had fallen 80% and that such fuel cells could be manufactured for $51/kW, assuming high-volume manufacturing cost savings.[36] Ballard Power Systems also published similar data. Their 2005 figure was $73 USD/kW (based on high volume manufacturing estimates), which they said was on track to achieve the U.S.
Department of Energy's 2012 goal of $30 USD/kW. This would achieve closer parity with internal combustion engines for automotive applications, allowing a 100 kW fuel cell to be produced for $3000. 100 kW is about 134 hp.[37]
6.2 Freezing conditions: Temperatures below freezing are a concern with fuel cells operations. Operational fuel cells have an internal vaporous water environment that could solidify if the fuel cell and contents are not kept above 0° Celsius (32°F). Most fuel cell designs are not as yet robust enough to survive in below-freezing environments. Frozen solid, especially before start up, they would not be able to begin working. Once running though, heat is a byproduct of the fuel cell process, which would keep the fuel cell at an adequate operational temperature to function correctly. This makes startup of the fuel cell a concern in cold weather operation. Places such as Alaska where temperatures can reach −40 °C (−40 °F) at startup would not be able to use early model fuel cells. Ballard announced in 2006 that it had already hit the U.S. DoE's 2010 target for cold weather starting which was 50% power achieved in 30 seconds at -20 °C.[38]Fuel cells have startup and long term reliability problems. 6.3 Service life: Although service life is coupled to cost, fuel cells have to be compared to existing machines with a service life in excess of 5000 hours[40] for stationary and light-duty. Marine PEM fuel cells reached the target in 2004.[41] Curre y like in the bus trials which are targeted up to a service life of 30,000 hours.
7. HYDROGEN:
Hydrogen does not come as a pre-existing source of energy like fossil fuels, but is first produced and then stored as a carrier, much like a battery. Hydrogen for vehicle uses needs to be produced using either renewable or non-renewable energy sources. A suggested benefit of largescale deployment of hydrogen vehicles is that it could lead to decreased emissions of greenhouse gases and ozone precursors.[43]
According to the United States Department of Energy "Producing hydrogen from natural gas does result in some greenhouse gas emissions. When compared to ICE vehicles using gasoline, however, fuel cell vehicles using hydrogen produced from natural gas reduce greenhouse gas emissions by 60%.[44] While methods of hydrogen production that do not use fossil fuel would be more sustainable,[45] currently renewable energy represents only a small percentage of energy generated, and power produced from renewable sources can be used in electric vehicles and for non-vehicle applications.[46] 7.1 Production: The molecular hydrogen needed as an on-board fuel for hydrogen vehicles can be obtained through many thermochemical methods utilizing natural gas, coal (by a process known as coal gasification), liquefied petroleum gas, biomass ( biomass gasification), by a process called thermolysis, or as a microbial waste product called biohydrogen or Biological hydrogen production. 95% of hydrogen is produced using natural gas,[50] and 85% of hydrogen produced is used to remove sulfur from gasoline. Hydrogen can also be produced from water by electrolysis or by chemical reduction using chemical hydrides or aluminum.[51] Current technologies for manufacturing hydrogen use energy in various forms, totaling between 25 and 50 percent of the higher heating value of the hydrogen fuel, used to produce, compress or liquefy, and transmit the hydrogen by pipeline or truck.[52] 7.2 Storage:
Compressed hydrogen storage mark Hydrogen has a very low volumetric energy density at ambient conditions, equal to about one-third that of methane. Even when the fuel is stored as liquid hydrogen in a cryogenic tank or in a compressed hydrogen storage tank , the volumetric energy density (megajoules per liter) is small relative to that of gasoline. Hydrogen has a three times higher energy density by mass compared to gasoline (143 MJ/kg versus 46.9 MJ/kg). Some research has been done into using special crystalline materials to store hydrogen at greater densities and at lower p ressures. 7.3 Infrastructure:
Hydrogen car fueling
The hydrogen infrastructure consists mainly of industrial hydrogen pipeline transport and hydrogen-equipped filling stations like those found on a hydrogen highway. Hydrogen stations which are not situated near a hydrogen pipeline can obtain supply via hydrogen tanks, compressed hydrogen tube trailers, liquid hydrogen tank trucks or dedicated onsite production.
Hydrogen use would require the alteration of industry and transport on a scale never seen before in history. For example, according to GM, 70% of the U.S. population lives near a hydrogen-generating facility but has little access to hydrogen, despite its wide availability for commercial use.[60] The distribution of hydrogen fuel for vehicles throughout the U.S. would require new hydrogen stations costing, by some estimates, 20 billion dollars.[61] and 4.6 billion in the EU.[62] Other estimates place the cost as high as half trillion dollars in the United States alone. [63]
7.4 Codes and standards: Hydrogen codes and standards, as well as codes and technical standards for hydrogen safety and the storage of hydrogen, have been identified as an institutional barrier to deploying hydrogen technologies and developing a hydrogen economy. To enable the commercialization of hydrogen in consumer products, new codes and standards must be developed and adopted by federal, state and local governments. 8. CRITICISM:
Critics claim the time frame for overcoming the technical and economic challenges to implementing wide-scale use of hydrogen vehicles is likely to last for at least several decades, and hydrogen vehicles may never become broadly available.[46][68] They claim that the focus on the use of the hydrogen car is a dangerous detour from more readily available solutions to reducing the use of fossil fuels in vehicles.[69] In May 2008, Wired News reported that "experts say it will be 40 years or more before hydrogen has any meaningful impact on gasoline
consumption or global warming, and we can't afford to wait that long. In the meantime, fuel cells are diverting resources from more immediate solutions. The Washington Post asked in November 2009, "But why would you want to store
energy in the form of hydrogen and then use that hydrogen to produce electricity for a motor, when electrical energy is already waiting to be sucked out of sockets all over America and stored in auto batteries"? The paper concluded that commercializing hydrogen cars is "stupendously difficult and probably pointless. That's why, for the foreseeable future, the hydrogen car will remain a tailpipe dream".[50] 9. COMPARISON WITH OTHER TYPES OF ALTERNATIVE FUEL VEHICLE :
Hydrogen vehicles are one of a number of proposed alternatives to the modern fossil fuel powered vehicle infrastructure.
Plug-in hybrids Plug-in hybrid electric vehicles, or PHEVs, are hybrid vehicles that can be plugged into the electric grid and contain an electric motor and also an ICE or other engine. The Chevrolet Volt, the first commercially-manufactured PHEV, became commercially available in some U.S. states in 2010 and in more locations in 2011. The PHEV concept augments standard hybrid electric vehicles with the ability to recharge their batteries from an external source while parked, enabling increased use of the vehicle's electric motors while reducing their reliance on internal combustion engines. The infrastructure required to charge PHEVs is already in place, [81] and transmission of power from grid to car is about 93% efficient.[82] The battery needs to be cooled; the GM Volt's battery has 4 coolers and two radiators.[85] As of 2009, "the total well-to-wheels efficiency with which a hydrogen fuel cell vehicle might utilize renewable electricity is roughly 20% (although that number could rise to 25% or a little higher with the kind of multiple technology breakthroughs required to enable a hydrogen economy).
The well-to-wheels efficiency of charging an onboard battery and then discharging it to run an electric motor in a PHEV or EV, however, is 80% (and could be higher in the future)— four times more efficient than current hydrogen fuel cell vehicle pathways."[49] A 2006 article in Scientific American argued that PHEVs, rather than hydrogen vehicles, would become standard
in the automobile industry.[86][87] A December 2009 study at UC Davis found that, over their lifetimes, PHEVs will emit less carbon than current vehicles, while hydrogen cars will emit more carbon than gasoline vehicles.[76]
Natural gas ICE-based CNG or LNG vehicles ( Natural gas vehicles or NGVs) use Natural gas or Biogas as a fuel source. Natural gas has a higher energy density than hydrogen gas. Natural gas powered vehicles have a lower carbon dioxide footprint than ICE vehicles. When using Biogas, NGVs become carbon neutral vehicles that run on animal waste.[88] CNG vehicles have been available for several years, and there is sufficient infrastructure to provide both commercial and home refueling stations. In 2008, the ACEEE rated the Honda Civic GX, which uses compressed natural gas, as the greenest vehicle available.
10. HYDROGEN ECONOMY The hydrogen economy describes a new system in which our energy needs will be
predominantly met by hydrogen, rather than carbon-based
fossil fuels. According to the United States Department of Energy (DOE), their Hydrogen Program is dedicated to working with industry, academia, national laboratories, and federal and international agencies to: • “Overcome technical barriers through research and development of hydrogen production, delivery, and storage technologies, as well as fuel cell technologies for transportation, distributed stationary power, and portable power applications,” • “Address safety concerns and develop model codes and standards,” • “Validate and demonstrate hydrogen and fuel cell technologies in realworld conditions, and”
Cooperation between national and international organizations will be vital to making the transition to this new economy. Each segment of this network will bring perspectives unique to their target applications. In this way, component technologies can be developed independently, and then integrated with other technologies to form the complete infrastructure of the hydrogen economy.
10.1.1Fuel Cell Cost and Durability: - Information and statistical data for concept and developmental fuel
cell vehicles is often limited and proprietary. Validation is required for vehicle drivability, operation, and survivability in extreme climates, and emissions from hydrogen internal combustion engines (ICE). Although various
components have been tested and
validated
independently,
validation of integrated systems is necessary for system development.
Hydrogen Storage – Current technology does not meet the requirements for large scale
transportation or stationary applications. Capital cost, long-term durability, fast-fill dispensing efficiency, and structural integrity of hydrogen storage system must be addressed before the technology can be commercially available to a wide market. Research and development is needed to address performance, failure, and operating cycle life in real-world applications.
10.2 Hydrogen Production and Delivery
– Currently the cost of hydrogen production is high, the availability of
hydrogen
production
systems
is
low,
and
production
and
delivery
technologies are still in their early stages of development. Data is limited for integrated coal-to-hydrogen/power plants with sequestration options, the high-temperature
production
of
hydrogen
from
nuclear
power,
and
renewable hydrogen production systems. Delivery options must be developed, tested, and alidated for every potential production technology.
10.3 Public Acceptance: – In order to foster acceptance of the hydrogen economy, the public
will need to be educated, personnel will need to be trained to operate and maintain the infrastructure, and codes and standards will need to be developed and adopted The design of the Station is a step toward making available a real world application of portable hydrogen production and refueling technologies. This project and projects like it help to demonstrate that the technical and safety barriers that currently stand in the way of widespread commercial acceptance of these technologies can be overcome.
11. APPLICATIONS:
11.1 Automobiles:
Ford Edge hydrogen-electric plug-in hybrid concept Many companies are currently researching the feasibility of building hydrogen cars, and some automobile manufacturers have begun developing hydrogen cars (see list of fuel cell vehicles). Funding has come from both private and government sources. However, the Ford Motor Company has dropped its plans to develop hydrogen cars, stating that "The next major step in Ford’s plan is to increase over time the volume of electrified vehicles".[4] 11.2 Buses:
Fuel cell buses (as opposed to hydrogen fueled buses) are being
trialed by several manufacturers in different locations. The Fuel Cell Bus Club is a global fuel cell bus testing collaboration. Hydrogen was first stored in roof
mounted tanks, although
models are now
incorporating onboard tanks. Some double deck models use between floor tanks.
11.3 Bicycles: Pearl Hydrogen Power Sources of Shanghai, China, unveiled a hydrogen bicycle at the 9th China International Exhibition on Gas Technology, Equipment and Applications in 2007. 11.4 Motorcycles and scooters: ENV develops electric motorcycles powered by a hydrogen fuel cell, including the Crosscage and Biplane. Other manufacturers as Vectrix are working on hydrogen scooters.[19]
Finally, hydrogen fuel cell-electric hybrid scooters are being made such as the Suzuki Burgman Fuel cell scooter and the FHybrid. 11.5 Airplanes: .
The Boeing Fuel Cell Demonstrator powered by a hydrogen fuel cell Companies such as Boeing, Lange Aviation, and the German Aerospace Center pursue hydrogen as fuel for manned and unmanned airplanes. In February 2008 Boeing tested a manned flight of a small aircraft powered by a hydrogen fuel cell. Unmanned hydrogen planes have also been tested.[24]
11.6 Fork trucks: A truck is a hydrogen fueled, internal combustion engine powered industrial forklift truck used for lifting and transporting materials. The first production HICE forklift truck based on the Linde X39 Diesel was presented at an exposition in Hannover on May 27, 2008. It used a 2.0 litre, 43 kW diesel internal combustion engine converted to use hydrogen as a fuel with the use of a compressor and direct injection.[27][28] The hydrogen tank is filled with 26 liters of hydrogen at 350 bar pressure.
11.7 Rockets: Many large rockets use liquified cryogenic hydrogen as a propellant. In addition they use liquified cryogenic oxygen, and liquified cryogenic hydrogen in the space shuttle, to charge the fuel cells that power the electrical systems.[citation needed ] The biproduct of the fuel cell is water, and is used for drinking, and any other application that requires water in space. The oxygen is also used to provide the rocket engines with oxygen for better thrust in space, due to the lack of oxygen in space.[citation needed ] Just prior to a launch, the rocket fuel tanks are filled and chilled.
12. ADVANTAGES: 1. Vehicle propulsion would not contribute to carbon dioxide emissions.
13. DISADVANTAGES: The drawbacks of hydrogen use are low energy content per unit volume, high tankage weights, very high storage vessel pressures, the storage, transportation and filling of gaseous or liquid hydrogen in vehicles, the large investment in infrastructure that would be required to fuel vehicles, and the inefficiency of production processes.
14. FUTURE SCOPE: Carbon Nanotube and Related Storage Technologies
The status of hydrogen storage in advanced carbon materials is still unclear. In this subsection, we review briefly the status of carbon nanotube storage, both single-walled and double-walled, and graphite nanofiber stack storage. Other carbon-based storage technologies that have been proposed include alkali-doped graphite, fullerenes, and activated carbon.
High surface area and abundant pore volume in the nanostructured materials make these especially attractive as potential absorption storage materials. Some early work gave tantalizing results for hydrogen storage in carbon nanotubes. Ogden reported various conflicting, some excessively optimistic, results [1]. A query by this subcommittee to Prof. Mildred Dresselhaus of MIT about the achievable wt% (6.5 wt% has been suggested) brought this response [33]: 1. It is hard to say what is a reliable estimate of the hydrogen uptake number because of the differences in the reported levels by different groups, presumably doing similar measurements. The reasons for the different results between groups are not understood. 2. The 6.5% value is not yet achievable in my opinion. 3. The problem seems to be hard to me, arguing from a theoretical standpoint. However I would not discount the possibility of a breakthrough that might change the situation dramatically. So far it doesn’t seem to me that there is yet much available carefully controlled work.
16. CONCLUSION: The only proven system for hydrogen storage today that is practical for fuel cell vehicles is compressed gas high pressure tank storage. While this technology has the disadvantages of limited energy density and possibly high weight for the tank, it has been shown to workable with up to 70 GPa (10,000 psi) on-board storage tanks. Of the other hydrogen storage systems, advanced carbon materials have been especially intriguing possibilities. However, very mixed
experimental results have left us to conclude that these materials are far from proven to have adequate storage capacity. Further research is ongoing, but a breakthrough is needed to provide a foundation for confidence that carbon nano tubes or related materials will be able to satisfy storage requirements. Finally, new ideas in hydridation of metal-N-H systems are sufficiently interesting that they are being pursued and may lead to the development of practical storage systems.
REFERENCES:
^ "Wind-to-Hydrogen Project". Hydrogen and Fuel Cells Research. Golden, CO:
National Renewable Energy Laboratory, U.S. Department of Energy. September 2009. Retrieved 7 January 2010.
