Presentation on theme: "Energy Futures: Hydrogen and THE FUEL CELL. Sources of information: –Heliocentris “Energy through Hydrogen” Research notes –Thames and Kosmos “Fuel Cell."— Presentation transcript:
Energy Futures: Hydrogen and THE FUEL CELL
Sources of information: –Heliocentris “Energy through Hydrogen” Research notes –Thames and Kosmos “Fuel Cell Car and Experimtent Kit” Lab manual –World Fuel Cell Council: World Fuel Cell Council - WelcomeWorld Fuel Cell Council - Welcome
OUTLINE: Energy Futures: Hydrogen and FUEL CELLS From the sun to consumable energy (year 2000). From the sun to consumable energy (possible future). From the sun to energy: an overview. Where will the hydrogen come from? How will the hydrogen be used? How does a fuel cell work?
Summary Slide (cont.) What is a fuel cell system? What is the history of the fuel cell? What are some of the challenges facing fuel cell development? What about the infrastructure job market? Where are we now? Reality and vision… What are some of the issues that government agencies may need to address?
Introduction: From the sun to consumable energy (year 2000). The source of almost all energy on earth is the sun. Present energy consumption is dependent on fossil fuels. Fossil fuels create environmental problems.
Introduction: From the sun to consumable energy (possible future). In the future: solar, wind, and hydropower may be utilized to electrolyze water to produce hydrogen.
From the sun to energy: an overview.
Where will the hydrogen come from? Fossil fuels: –Examples: Coal / Oil / Methane (CH 4 ) –Hydrogen is obtained from fossil fuels by a process called reforming. –This is currently the cheapest method to obtain hydrogen.
Where will the hydrogen come from? Plants like corn… –Used to produce alcohols which have a significant amount of hydrogen: ethanol (C 2 H 5 OH). –Hydrogen is again obtained by the reforming process. Ethanol plant, Monroe WI
Where will the hydrogen come from? Water –Electrolysis (breaking up by electricity) of H 2 O Conventional – An electrical current is induced in a water and electrolyte (a substance that produces electrical current carrying ions) solution. Water is ionized (broken up into positive (H 2+ ) and negative (OH-) ions) and the ions collect at opposite electrodes. (Aswan dam, Egypt: largest H 2 production by electrolysis.) –The hydrogen gas is collected and may be used later as a fuel. –Demonstration: Electrolysis using a solar cell as an electrical source. Solid electrolyte membranes – When electrical current is applied to the water in a fuel cell, H 2 + protons move through a Proton Exchange Membrane (PEM) and unite with electrons (e- on the other side of the membrane to form hydrogen gas (H 2 ). – Demonstration: Electrolysis using a reversible PEM fuel cell.
How the Solar Cell works – pn Junction
Silicon Atomic Structure
The Entire Process
How will the hydrogen be used? Use it as any other flammable gas would be: –Gas grills have been converted to use hydrogen. –Internal combustion engines can be retrofitted for H 2. – – This may be the quickest way to implement a hydrogen economy but may not be the best long term solution. –Environmental pollutants are few but not zero.
How will the hydrogen be used? FUEL CELLS that use hydrogen are currently under development to replace internal combustion engines and for cogeneration of electricity and heat. –Fuel cells are 50%-60% efficient compared to internal combustion engines that are 15-20% efficient. –There are no moving parts and run silently. –There is little maintenance. –The fuel used is proportionate to the load. –There are no environmental pollutants. –The only byproducts are water and heat (which is why they are perfect for use in spacecraft!). Demonstration: Car with PEM running on hydrogen gas.
How does a fuel cell work? A model of a reversible PEM fuel cell. It changes water to H 2 and O 2 if electrical energy is supplied and H 2 and O 2 to water (H 2 O) if hydrogen is supplied.
Fuel Cell Animation
What is a fuel cell system?
What is the history of the fuel cell? Sir William Grove (a British lawyer) discovered the process by which fuel cells operate in 1839! Grove’s discovery was called a “gas battery” but had a very low energy capacity. Future development was slow mostly due to the rapid corrosion of the electrodes. In the 1950”s, Francis “Tom” Bacon succeeded in producing the first practical fuel cell. In the 1960’s the first PEM fuel cells were developed by General Electric and chosen by NASA for the space program. The fuel cell used a membrane that had a working lifetime of about 500 hours.
What is the history of the fuel cell? A few months later Dupont finished development on an improved membrane that had a lifetime of thousands of hours. NASA had already made its choice of the GE fuel cell membrane and this decision is thought to have held back the development of proton exchange membrane (PEM) fuel cells by at least 15 years! Modern emphasis on fuel cell development began in the 1980”s.
What are some of the challenges facing fuel cell development? How to increase the efficiency of the cells: –Currently 50% at full power and 60% at half power consumption. –Cogeneration (making use of the heat and electricity) reaches 90%. –Development of better materials that will produce more power from the cells. –Decreasing internal resistance when a stack of fuel cells is used.
What are some of the challenges facing fuel cell development? How to reduce the capital costs $$$$$$: –In the stationary power market, fuel cells would be competitive at a cost of $1500/Kilowatt… present cost is $4000! –In automobiles the competitive cost is $60- $100/Kilowatt!!!! –Possible reductions may be made in the areas of: Lower cost materials (platinum = $5000/pound and rhodium in the range of $9000/pound). Reducing the complexity of an entire system. Minimize temperature restraints. Scaling up and streamlining production.
What are some of the challenges facing fuel cell development? How to increase the rate of the chemical reactions associated with the hydrogen formation and the fuel cell: Reaction rates are increased by: –Higher temperatures. –Greater concentrations of reactants. –More surface area of any solid reactants. –Monitoring the frequency of light striking the reaction. –Catalysts (most research is being done in this area). Platinum is the chief catalyst and still is the best so research is directed at using the minimum amount possible.
What are some of the challenges facing fuel cell development? Developing safe and convenient hydrogen storage: –Hydrogen in not commonly thought of as a safe fuel… in part because of the belief that the Hindenburg disaster of 1937 was caused by a hydrogen explosion. Recent research however supports the theory that the rapid burn was caused by the flammable nature of the fabric covering! –In fact hydrogen is considered to be safer than gasoline: It quickly escapes upward into the atmosphere vs. flowing under a vehicle. It burns quickly and must have the right ratio of oxygen. Gasoline vapors are a known carcinogen…Hydrogen nontoxic. Vehicles with hydrogen storage have been tested and are safe.
But the challenge is……. Hydrogen is a very small molecule so storage and transport systems must be capable of keeping this small molecule contained…think about how a helium balloon quickly loses its gas…hydrogen would be even faster. Hydrogen is a gas and and as such requires a very large volume of storage capacity. To travel 300 miles using a PEM fuel cell would require 3600 liters (36 cubic meters) of hydrogen at normal temperature and pressure. –Liquifying hydrogen like we do propane (LP) is costly and the pressure in the tanks would be dangerously high. –Recent developments have concentrated on absorbing hydrogen into metal hydrides. It may be possible that the fuel for a 300 mile trip could be stored in a volume of 50 liters.
Storage challenges…. Hydrogen tanks fill the trunk of this sports car.
And some possible solutions???
What are some of the challenges facing fuel cell development? Development of a hydrogen production and distribution infrastructure. –Options for production are: large central solar stations electrolyzing water to hydrogen smaller on site production facilities. –There will be massive costs to convert refueling stations. Some estimate in the range of $300 billion in the USA alone! One must remember however that this cost will be spread over many years…the time frame for our last infrastructure change from horses to automobiles took 20 years.
And just think about the infrastructure job market… Hydrogen fuel production and distribution personnel will be in demand. Qualified service and maintenance personnel will be needed. Continued research and development will be imperative.
Where are we now? There are several types of fuel cells in various stages of development:
Where are we now? International cooperation to develop a hydrogen economy is strong: –November 2003: the world’s leading fuel cell organizations announced that they have entered into a cooperative agreement to advance commercialization of fuel cells worldwide…represented are more than 300 businesses and research institutions! –Governments are negotiating multilateral programs to promote fuel cells and hydrogen. –Automakers from around the world…Asia, Europe, America are forming coalitions to develop fuel cell cars.
Where are we now? Two broad categories of fuel cell technology are developing: Stationary or on site for homes and businesses and mobile, especially in the area of transportation. STATIONARY: –Dow Chemical Company and General Motors have agreed to develop the largest fuel cell installation (June 2003). This should ultimately produce enough electricity to power homes. The benefit of this plan is that GM will move from building lab specimens to production fuel cells and DOW will acquire clean energy. –A few homes have smaller solar/hydrogen fuel cell systems for cogeneration of electricity and heat.
Where are we now? MOBILE: –Almost forgotten is that there is a real possibility that fuel cells will replace batteries in consumer electronics…just add a few milliliters of alcohol when needed! –PEM fuel cells are the area of most research and development for automobiles. At the November 2003 Tokyo Motor show Toyota, Nissan, and Suzuki concept cars drew the most attention, but… –Japan carmakers like Mazda were also showing hydrogen internal combustion engines at the show. –January 2004, California unveils a plan to provide an Interstate hydrogen fueling network of 200 stations within the next decade.
Reality and vision… A methanol fuel cell could provide power to small electronic devices up to 20 times longer than a battery. The last problem for this technology is to prove that the cells can be mass produced cheaper than batteries. Some banks and organizations that cannot afford to lose power are using fuel cells to provide complete security of supply. More to come? Provided there is a fuel supply, the fuel cell can be put in any size needed at a point of use and provide 10’s of thousands of uninterrupted hours of electricity. Our high-voltage national electrical grid is not very efficient. A combination of fuel cell, photovoltaic, and solar energy technology could eventually replace the grid with an efficient, low polluting source of energy.
What are some of the issues that government agencies may need to address? Of course ….funding! Codes and standards for permits will need to be determined and enforced! Will unmanned operation be generally permitted? Will there be any emissions regulations? Will the fuel be taxed like gasoline? Can insurance for these installations be obtained? What depreciation schedules will be allowed?