1. Hydrogen Fuel Cell Technology

2. FUEL CELL TECHNOLOGY
Technology overview
Hydrogen fuel development

3. What is a Fuel Cell?
A Fuel Cell is an electrochemical device that combines hydrogen and oxygen to produce electricity, with water and heat as its by-product.

4. Why is Fuel Cell Technology Important?
Since conversion of the fuel to energy takes place via an electrochemical process, not combustion
It is a clean, quiet and highly efficient process- two to three times more efficient than fuel burning.

5. How does a Fuel Cell work?
It operates similarly to a battery, but it does not run down nor does it require recharging
As long as fuel is supplied, a Fuel Cell will produce both energy and heat

6. How does a Fuel Cell work?
A Fuel Cell consists of two catalyst coated electrodes surrounding an electrolyte
One electrode is an anode and the other is a cathode

7. How does a Fuel Cell work?
The process begins when Hydrogen molecules enter the anode
The catalyst coating separates hydrogen’s negatively charged electrons from the positively charged protons

8. How does a Fuel Cell work?
The electrolyte allows the protons to pass through to the cathode, but not the electrons
Instead the electrons are directed through an external circuit which creates electrical current

9. How does a Fuel Cell work?
While the electrons pass through the external circuit, oxygen molecules pass through the cathode
There the oxygen and the protons combine with the electrons after they have passed through the external circuit
When the oxygen and the protons combine with the electrons it produces water and heat

10. How does a Fuel Cell work?

11. How does a Fuel Cell work?
Individual fuel cells can then be placed in a series to form a fuel cell stack
The stack can be used in a system to power a vehicle or to provide stationary power to a building

12. Major Types of Fuel Cells
In general all fuel cells have the same basic configuration - an electrolyte and two electrodes
Different types of fuel cells are classified by the kind of electrolyte used
The type of electrolyte used determines the kind of chemical reactions that take place and the temperature range of operation

13. Major Types of Fuel Cells
Proton Exchange Membrane (PEM)
This is the leading cell type for passenger car application
Uses a polymer membrane as the electrolyte
Operates at a relatively low temperature, about 175 degrees
Has a high power density, can vary its output quickly and is suited for applications where quick startup is required making it popular for automobiles
Sensitive to fuel impurities

14. Major Types of Fuel Cells
Direct Methanol (a subset of PEM)
Expected efficiencies of 40% plus low operating temperatures between degrees
Also uses a polymer membrane as the electrolyte
Different from PEM because the anode catalyst is able to draw hydrogen from methanol without a reformer
Used more for small portable power applications, possibly cell phones and laptops

15. Major Types of Fuel Cells
Phosphoric Acid
This is the most commercially developed fuel cell
It generates electricity at more than 40% efficiency
Nearly 85% of the steam produced can be used for cogeneration
Uses liquid phosphoric acid as the electrolyte and operates at about 450 degrees F
One main advantage is that it can use impure hydrogen as fuel

16. Major Types of Fuel Cells
Molten Carbonate
Promises high fuel-to-electricity efficiency and the ability to utilize coal based fuels
Uses an electrolyte composed of a molten carbonate salt mixture
Require carbon dioxide and oxygen to be delivered to the cathode
Operates at extremely high temperatures 1200 degrees
Primarily targeted for use as electric utility applications
Have been operated on hydrogen, carbon monoxide, natural gas, propane, landfill gas, marine diesel and simulated coal gasification products

17. Major Types of Fuel Cells
Molten Carbonate Fuel Cell
Because of the extreme high temperatures, non-precious metals can be used as catalysts at the anode and cathode which helps reduces cost
Disadvantage is durability
The high temperature required and the corrosive electrolyte accelerate breakdown and corrosion inside the fuel cell

18. Major Types of Fuel Cells
Solid Oxide
Uses a hard, non-porous ceramic compound as the electrolyte
Can reach 60% power-generating efficiency
Operates at extremely high temperatures 1800 degrees
Used mainly for large, high powered applications such as industrial generating stations, mainly because it requires such high temperatures

19. Major Types of Fuel Cells
Alkaline
Used mainly by military and space programs
Can reach 70% power generating efficiency, but considered to costly for transportation applications
Used on the Apollo spacecraft to provide electricity and drinking water
Uses a solution of potassium hydroxide in water as the electrolyte and operates at degrees
Can use a variety of non-precious metals as catalyst at the anode and cathode

20. Major Types of Fuel Cells
Alkaline Fuel Cell
Requires pure hydrogen and oxygen because it is very susceptible to carbon contamination
Purification process of the hydrogen and oxygen is costly
Susceptibility to poisoning affects cell’s lifetime which also affects the cost

21. Major Types of Fuel Cells
Regenerative Fuel Cells
Currently researched by NASA
This type of fuel cell involves a closed loop form of power generation
Uses solar energy to separate water into hydrogen and oxygen
Hydrogen and oxygen are fed into the fuel cell generating electricity, heat and water
The water byproduct is then recirculated back to the solar-powered electrolyser beginning the process again

22. Importance of Hydrogen
Fuel Cells require highly purified hydrogen as a fuel
Researchers are developing a wide range of technologies to produce hydrogen economically from a variety of resources in environmentally friendly ways

23. Importance of Hydrogen
Hydrogen is a secondary energy resource, meaning it must be made from another fuel
Hydrogen can be produced from a wide variety of energy resources including:
Fossil fuels, such as natural gas and coal
Nuclear energy
Renewable resources, such as solar,water, wind and biomass

24. Hydrogen Production
The biggest challenge regarding hydrogen production is the cost
Reducing the cost of hydrogen production so as to compete in the transportation sector with conventional fuels on a per-mile basis is a significant hurdle to Fuel Cell’s success in the commercial marketplace

25. Hydrogen Production
There are three general categories of Hydrogen production
Thermal Processes
Electrolyte Processes
Photolytic Processes

26. Hydrogen Production Thermal Processes Natural Gas Reforming
Gasification
Renewable Liquid Reforming

27. Hydrogen Production Natural Gas Reforming Steam Methane Reforming
Hydrogen is produced from methane in natural gas using high-temperature steam
Methane reacts with the steam in presence of a catalyst to produce hydrogen
This process accounts for about 95% of the hydrogen used today in the U.S.
Partial oxidation
Produces hydrogen by burning methane in air

28. Hydrogen Production Gasification
Process in which coal or biomass is converted into gaseous components by applying heat under pressure and in the presence of steam
A subsequent series of chemical reactions produces a synthesis gas which reacts with steam to produce more hydrogen that can be separated

29. Hydrogen Production Renewable Liquid Reforming
Biomass is processed to make renewable liquid fuels, such as ethanol or bio-oil, that are then reacted with high-temperature steam to produce hydrogen
This process is very similar to reforming natural gas

30. Hydrogen Production Electrolytic Processes
Electrolytic processes use an electric current to split water into hydrogen and oxygen
The electricity required can be generated by using renewable energy technologies such as wind, solar, geothermal and hydroelectric power

31. Hydrogen Production Photolytic Processes
Uses light energy to split water into hydrogen and oxygen
These processes are in the very early stages of research but offer the possibility of hydrogen production which is cost effective and has a low environmental impact

32. Hydrogen Production
Auto manufacturers have worked on developing technology that would allow fuel cell cars to continue using gasoline
A “reformer” on the fuel cell car would convert the gasoline to hydrogen onboard the automobile
Funding for this technology has been pulled due to unsatisfactory efficiency
Energy, Economics, and the Environment. Cases and Materials Second Edition. Chapter 15 Energy in Transportation p. 1200

33. How will the hydrogen be stored?
Developing safe, reliable, compact and cost-effective hydrogen storage is one of the biggest challenges to widespread use of fuel cell technology
Hydrogen has physical characteristics that make it difficult to store large quantities without taking up a great deal of space

34. How will the hydrogen be stored?
Hydrogen will need to be stored onboard vehicles, at hydrogen production sites, refueling stations and stationary power sites
Hydrogen has a very high energy content by weight (3x more than gasoline) and a very low energy content by volume (4x less than gasoline)

35. How will the hydrogen be stored?
If the hydrogen is compressed and stored at room temperature under moderate pressure, too large a fuel tank would be required
Researchers are trying to find light-weight, safe, composite materials that can help reduce the weight and volume of compressed gas storage systems
Energy, Economics, and the Environment. Cases and Materials Second Edition. Chapter 15 Energy in Transportation p. 1199

36. How will the hydrogen be stored?
Liquid hydrogen could be kept in a smaller tank than gaseous hydrogen, but liquefying hydrogen is complicated and not energy efficient
Liquid hydrogen is also extremely sensitive to heat and expands significantly when warmed by even a few degrees, thus the tank insulation required affects the weight and volume that can be stored
Energy, Economics, and the Environment. Cases and Materials Second Edition. Chapter 15 Energy in Transportation p. 1199

37. How will the hydrogen be stored?
If the hydrogen is compressed and cryogenically frozen it will take up a very small amount of space requiring a smaller tank, but it must be kept supercold- around -120 to degrees Celsius

38. How will the hydrogen be stored?
Scientists are researching Materials-based storage
This involves tightly binding hydrogen atoms or molecules with other elements in a compound to store larger quantities of hydrogen in smaller volumes at low pressure near room temperature
This technology is considered very promising but additional research is needed to overcome problems dealing with capacity, cost, life cycle impacts and the uptake and release of hydrogen

39. How will the hydrogen be stored?
Because hydrogen is thought to be an alternative fuel for automobiles, much of the research for hydrogen storage is focused on onboard vehicles
Scientists are attempting to develop technology that can rival the performance and cost of gasoline fuel storage systems

40. How will the hydrogen be stored?
Using current storage technology, in order to place a sufficient amount of hydrogen onboard a vehicle to provide 300-mile driving range the tank would be larger that the trunk of a typical automobile
This large of a tank would add to the overall weight of the car and reduce fuel economy

41. How can Fuel Cell technology be used?
Transportation
Stationary Power Stations
Telecommunications
Micro Power

42. How can Fuel Cell technology be used?
Transportation
All major automakers are working to commercialize a fuel cell car
Automakers and experts speculate that a fuel cell vehicle will be commercialized by 2010
50 fuel cell buses are currently in use in North and South America, Europe, Asia and Australia
Trains, planes, boats, scooters, forklifts and even bicycles are utilizing fuel cell technology as well

43. How can Fuel Cell technology be used?
Stationary Power Stations
Over 2,500 fuel cell systems have been installed all over the world in hospitals, nursing homes, hotels, office buildings, schools and utility power plants
Most of these systems are either connected to the electric grid to provide supplemental power and backup assurance or as a grid-independent generator for locations that are inaccessible by power lines

44. How can Fuel Cell technology be used?
Telecommunications
Due to computers, the Internet and sophisticated communication networks there is a need for an incredibly reliable power source
Fuel Cells have been proven to be % reliable

45. How can Fuel Cell technology be used?
Micro Power
Consumer electronics could gain drastically longer battery power with Fuel Cell technology
Cell phones can be powered for 30 days without recharging
Laptops can be powered for 20 hours without recharging

46. What are the benefits of Fuel Cell technology?
Physical Security
Reliability
Efficiency
Environmental Benefits
Battery Replacement/Alternative
Military Applications

47. What are the benefits of Fuel Cell technology?
Physical Security
Both central station power generation and long distance, high voltage power grids can be terrorist targets in an attempt to cripple our energy infrastructure
Fuel Cells allow the country to discontinue reliance on these potential targets

48. What are the benefits of Fuel Cell technology?
Reliability
U.S. businesses lose $29 Billion a year from computer failures due to power outages
More reliable power from fuel cells would prevent loss of dollars for U.S. Businesses
Properly configured fuel cells would result in less than one minute of down time in a six year period

49. What are the benefits of Fuel Cell technology?
Efficiency
Because no fuel is burned to make energy, fuel cells are fundamentally more efficient than combustion systems
Additionally when the heat comes off of the fuel cell system it can be captured for beneficial purposes
This is called Cogeneration

50. What are the benefits of Fuel Cell technology?
Efficiency
The gasoline engine in a conventional car is less than 20% efficient in converting the chemical energy in gasoline into power
Fuel Cell motors are much more efficient and use 40-60% of the hydrogen’s energy
Fuel Cell cars would lead to a 50% reduction in fuel consumption
Fuel Cell vehicles can be up to 3 times more efficient than internal combustion engines

51. What are the benefits of Fuel Cell technology?
Efficiency
Fuel Cell power generation systems in operation today achieve 40% to 50% fuel-to-electricity efficiency
In combination with a turbine, electrical efficiencies can exceed 60%
When Cogeneration is used, fuel utilization can exceed 85%

52. What are the benefits of Fuel Cell technology?
Environmental Benefits
Fuels cells can reduce air pollution today and offer the possibility of eliminating pollution in the future

53. What are the benefits of Fuel Cell technology?
Environmental Benefits of Fuel Cell Power Generation
A fuel cell power plant may create less than one ounce of pollution per 1,000 kilowatt-hours of electricity produced
Conventional combustion generating systems produce 25 pounds of pollutants for the same electricity

54. What are the benefits of Fuel Cell technology?
Environmental Benefits of Fuel Cell Vehicles
Fuel Cell Vehicles with hydrogen stored on-board produce ZERO POLLUTION in the conventional sense
The only byproducts of these Fuel Cell vehicles are water and heat

55. What are the benefits of Fuel Cell technology?
Environmental Benefits of Fuel Cell Vehicles
Fuel Cell Vehicles with a reformer on board to convert a liquid fuel to hydrogen would produce a small amount of pollutants, but it would be 90% less than the pollutants produced from combustion engines

56. What are the benefits of Fuel Cell technology?
Battery replacement/alternative
Fuel Cell replacements for batteries would offer much longer operating life in a packaged of lighter or equal weight
Additionally, Fuel Cell replacements would have an environmental advantage over batteries, since certain kinds of batteries require special disposal treatment

57. What are the benefits of Fuel Cell technology?
Military Applications
Fuel Cell technology in the military can help save lives because it reduces telltale heat and noise in combat
Handheld battlefield computers can be powered for 10 times longer with Fuel Cell power meaning soldiers could rely on their computers in the field for longer periods of time

58. Challenges to Fuel Cell Technology
Cost
The cost of fuel cells must be reduced to compete with conventional technologies
Conventional internal combustion engines cost $25-$35/kW; a fuel cell system would need to cost $30/kW to be competitive

59. Challenges to Fuel Cell Technology
Durability and Reliability
Durability of fuel cell systems have not yet been adequately established
The durability standard for automobiles is approximately 150,000 miles and the ability to function under normal vehicle operating conditions
For stationary systems 40,000 hours of reliable operation in a temperature range of -35 degree Celsius to 40 degrees Celsius will be required for market acceptance

60. Challenges to Fuel Cell Technology
System Size
The size and weight of current fuel cell systems must be reduced to attain market acceptance, especially with automobiles

61. Conclusion Promising technology
Most viable for niche market use in the near future
Widespread marketplace acceptance and use is still many years away