Chem 1100 Lecture 18Outline of Last Lecture I. Energy/ElectricityII. BatteriesIII. Why not use batteries to power everything?Outline of Current Lecture I. Fuel CellsII. Methanol Fuel CellsIII. Gasoline Fuel CellsIV. Hydrogen FuelV. Sources of HydrogenVI. Electric CarsCurrent LectureI. Fuel Cellsa. How they work?i. Force hydrogen atoms through membranes ii. Carbon atoms through wireiii. No flame, no solids needed all gasiv. Little heat (efficient) good thing bc we aren’t losing as much energyv. Produces = H2O (environment friendly)vi. Unused Hydrogen and Oxygen can be put back in the fuel cellvii. It’s 40-45% efficient which compares to gas engines (20-30%) and diesel (30-35%)b. What are they made of?These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.c. Fd. Fuel Cell - Carsi. No nitrogen oxidesii. Low to no C02 emissionsiii. Hydrogen and methanol could be renewable resources? They are doing research on it now.iv. Engine: no moving parts in engine. The fewer moving parts you have the less you have to repair and the easier it is to repair. It’s longer lasting. e. Advantagesi. Will run as long as your fuel/hydrogen/methanol tankii. It’s a lot faster than it takes to recharge an electric cars batteryiii. The reaction is slower and there’s not as much power in a short timeiv. Upfront costs for these fuels cells are expensive but cheaper in the long run.II. Methanol Fuel Cellsa. Problemsb. Production of CO & CO2c. Fuel crossover – cross membrane and burn less efficientd. 25 mpg ($3 a gallon)e. Vehicle cost about $200,000f. Very expensive^^^^ but very durable and would last you your entire lifeIII. Gasoline Fuel Cella. Gasoline Vapor H2 and Co2 = electricityb. Uses pre-existing fuel systemc. More efficient than int. comb. Engined. Not losing energy due to heat loss Consuming less gasolineIV. Hydrogen Fuela. Hydrogen in general is very reactive and explosiveb. Fuel Cells: 2H2 + O2 2H2O + 572 kJc. Output: 286 kJ/mol H2d. The process below requires A LOT of energyV. Sources of Hydrogena. Hydrogen is the most plentiful element (93%)b. Very reactive tied up in compoundsc. It must be extractedd. Where do we get the energy to extract it?e. Not from power plants: they are only 20-30% efficient (50% at best)f. Heat decomposition? Takes too much energy Need 5000 degrees Cg. Catalysis: Water gas reactionh. The objective is to make the catalyst react at low temperaturesi. Making ammonia and transporting in that form but they are afraid drug dealers would steal the ammonia to make meth.j. Storage in Nanotubes: tubes of carbon atomsk. They are heavy and explosive and have to be transported in pressurized cylindersVI. Electric Carsa. Lead storage batteriesb. No pollutants releasedc. Don’t need fueld. NiMH and Li-Ione. Light better mileagef. Last life of vehicleg. Quick rechargeh. Needs frequent recharge short rangei. Recharge Stations would be needed in many placesj. Need power plants to fuel these recharge stationsk. Power plants = pollutantsl. Toxic materials (point source) – limited
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