Hey Prof, I am not a big believer in the global warming theory mainly because the science involved in supporting it is usually surrounded with political hype and the science that debunks it appears to be more based on proper scientific method and theories.
What is your take on this:
http://junkscience.com/Greenhouse/index.html
Also, the whole reason for scrapping the hydrogen technology is that hydrogen is not readily found in it pure form, i.e., you have to add energy to extract it, such as the electrolysis of water, etc. From a global perspective, hydrogen becomes only an energy transport mechanism, not a source of energy. It is basically the same thing as a rechargeable battery. You have to get the initial energy from some where. Petroleum and coal are typically those sources. Because of this, using hydrogen doesn't really change the argument of where the energy comes from. It just obfuscates the source a bit. Plus, there are some inherent inefficiencies in converting potential energy to from one storage form to another. So at best, the hydrogen economy takes the existing energy reserves and multiplies them by 90%. Typically, it is more efficient to just stick with the source (i.e., burn fuel directly in the vehicle or coal and/or natural gas directly in the power plant, etc).
The only green solutions are solar, wind, geothermal, and possibly nuclear. But, since autos are only 17% of the source of CO2 and power plants make up most of the remainder, it would really make more sense to try to convert the power plants to a green technology and leave the vehicles alone.
Oh, and just for argument's sake, does anyone know why gasoline and diesel were selected as the fuels for automotive transportation?
It is because out of all the distillates from petroleum they are they most suitable for portable power production. They could have used any other chemical as a fuel, but these two fuels have the best properties for the least amount of energy input to refine. You get the most energy out with the least energy input. In a sense, they are the greenest fuels available and are liquids at room temperature.
Everyone jumps on the alternative fuel bandwagon, but one of the biggest reasons that gasoline and diesel are used is that they can be transported at normal temperatures and pressures. To illustrate my point: natural gas as a motor fuel typically produces less unburned hydrocarbon emissions, and similar CO2 emissions as compared to gasoline, but during the refueling process, has over ten times the leakage to atmosphere due to it having to be stored at 4000psi or so in cylinders. In practical use, much more unburned methane emissions are caused just by simply refueling the cylinders. The amount of raw hydrocarbon emissions emitted during the normal course of vehicle use is actually higher with natural gas vehicles than gasoline vehicles because of nature of the fuel and storage requirements and therefore makes a natural gas vehicles more of a green house gas polluter than a gasoline vehicle.
But, since natural gas vehicles make up such a small percentage of the overall fleet of vehicles, everyone seems to just turn their heads and look the other way when this is brought up. It's funny how politics seems to trump science and reality.
