thegoat4
08-15-2008, 07:34 AM
We need to put our heads together and clarifiy what we mean when we start talking about alternative fuels. My suggestions:
Fuel: as far as internal (or external) combustion engines are concerned, anything that qualifies as a fuel is made up of molecules that have chemical bonds which when broken or rearranged yield more energy than was required to break or rearrange those bonds in the first place. You can extract the energy stored in those bonds to perform useful work. ie, a few miliamps of spark and a few horsepower of compression burn a cylinder full of gasoline vapors that yield a whole bunch of heat and pressure pushing back at the piston.
Energy source: this is limited to the above definition of fuel, so no nuclear, no 100% solar car. Any common fuel that qualifies as an energy source gets its stored energy through biological processes one way or another. Oil is what's left of old dead crap. Coal and natural gas are more of the same. Biofuels are made up from harvested crops, or fresh dead crap. The collecting/harvesting and refining processes consume some power, but it's always less than what the refined fuels will yield. The difference in energy ultimately comes from sunlight and chemical energy stored in the soil and fertilizers.
Energy storage: these are fuels that must be manufatured. Usually, manufacturing these fuels requires burning an energy source type fuel initially. The process of manufacturing these fuels will always consume more energy than what the finished fuel will yield. Brown's gas (HHO) is manufactured (in a vehicle, anyway) by burning gas to run the alternator to generate electricity to disassociate the water molecules. This process will consume more energy than the resulting gas can yield, so HHO is an energy storage type fuel.
These definitions leave out some things. There are some metals that can be "burned" to get energy. Likewise there are other non-biological sources of energy that can still be "burned," but they're uncommon enough in automotive engines to be left out. No mention has been made of environmental side-effects like how you deal with the piles of glycerin left over from biodiesel manufacture.
Anyone want to add to the above?
Fuel: as far as internal (or external) combustion engines are concerned, anything that qualifies as a fuel is made up of molecules that have chemical bonds which when broken or rearranged yield more energy than was required to break or rearrange those bonds in the first place. You can extract the energy stored in those bonds to perform useful work. ie, a few miliamps of spark and a few horsepower of compression burn a cylinder full of gasoline vapors that yield a whole bunch of heat and pressure pushing back at the piston.
Energy source: this is limited to the above definition of fuel, so no nuclear, no 100% solar car. Any common fuel that qualifies as an energy source gets its stored energy through biological processes one way or another. Oil is what's left of old dead crap. Coal and natural gas are more of the same. Biofuels are made up from harvested crops, or fresh dead crap. The collecting/harvesting and refining processes consume some power, but it's always less than what the refined fuels will yield. The difference in energy ultimately comes from sunlight and chemical energy stored in the soil and fertilizers.
Energy storage: these are fuels that must be manufatured. Usually, manufacturing these fuels requires burning an energy source type fuel initially. The process of manufacturing these fuels will always consume more energy than what the finished fuel will yield. Brown's gas (HHO) is manufactured (in a vehicle, anyway) by burning gas to run the alternator to generate electricity to disassociate the water molecules. This process will consume more energy than the resulting gas can yield, so HHO is an energy storage type fuel.
These definitions leave out some things. There are some metals that can be "burned" to get energy. Likewise there are other non-biological sources of energy that can still be "burned," but they're uncommon enough in automotive engines to be left out. No mention has been made of environmental side-effects like how you deal with the piles of glycerin left over from biodiesel manufacture.
Anyone want to add to the above?