Transportation is a big problem. Assume that we no longer used oil (except for lubrication, etc... but not as a fuel). And assume that we collect solar or tidal energy and have all the electricity we could ever need.
How do you make, say, a car that runs on electricity and performs like a gasoline engine car?
That is, I want to be able to "refuel" it in under 10 minutes. I want 400 to 500 miles per "tank" of fuel and I want decent acceleration and lastly it's got to be safe in a crash (at least as safe as gasoline).
How do you store the energy in a compact, dense form that can be quickly "inserted" (poured, charged, etc...) into an automobile?
Batteries would work, but they have major disadvantages:
(1) It takes a long time to charge them. No 10 minute "fillup" is possible.
(2) They are very heavy.
(3) They don't have a lot of energy density (watts per pound). And the better a battery is, the more dangerous it is. A short circuit or even a mere overheat can cause a catastrophic fire, explosion and release of toxic gases.
(4) Most high performance batteries contain a lot of toxic materials like lithium metal, various metallic hydroxides, etc...
Well, how about using the electricity and converting water into hydrogen and oxygen, then use the hydrogen for fuel. It would burn clean (only exhaust product is water vapor if the combustion temperature is not allowed to get too high).
Hydrogen is the most powerful fuel there is... the most energy per unit mass. But, of course, it has problems:
(1) Hydrogen cannot be stored as a liquid in a closed tank. It needs to be stored in a HIGHLY insulated Dewar style tank (like a Thermos bottle - a two wall tank with a vacuum inside and silvered surfaces to reflect infrared) with the best insulation possible and allowed to vent to keep it's temperature low and it's pressure low. Else the tank would explode. That's why you see rockets on the launch pad spewing "steam"... the liquid oxygen and liquid hydrogen tanks are venting to keep the pressure down (and being constantly topped off by GSE (ground support equipment) as the liquids boil away at hundreds of gallons per minute!).
(2) Hydrogen (even liquid) is not very dense. It would take a large tank to hold a sufficient amount to be practical as a fuel. That's why the Saturn V moon rocket first stage used KEROSENE and liquid oxygen as propellant... because the improvement in power by using hydrogen would be outweighed by the much larger tanks it would require (and the increased air drag they would have caused). The second and third stages, however, did use hydrogen and oxygen (because up there air drag on larger tanks didn't exist, so it was better to use hydrogen THERE).
(3) Hydrogen has a wide explosive limit range in air (5% to 75%). That means virtually ANY hydrogen leak is a potential hazardous explosion waiting to happen.
(4) To store hydrogen in a closed tank, it needs to be "hydrided" ("dissolved" or "absorbed" in a carrier element). This means that a tank of hydrogen hydride contains even less hydrogen per a given tank size. A fuel tank the size of a semi truck would not be practical for a passenger car.
(5) Hydrogen does not lend itself well to "average dumbass driver filling his own tank" safely because of the chance of a leak and the wide explosive range.
(6) Hydrogen could be poured into a tank as a liquid, but the tank would need to be pre-chilled, otherwise most of a tankful's worth of hydrogen would be wasted just chilling down the tank before it would accept and hold liquid.
(7) A hydrogen HYDRIDE tank cannot be filled quickly. The hydriding process takes a lot of time.
Methane... CH4.. the C means "Carbon" and the global warming nuts would bitch about methane.
Now think about how to fuel commercial airliners without "fossil fuels". The problem is even bigger.
Gentlemen may prefer Blondes, but Real Men prefer Redheads!
Roger is correct- we have largely maxed out the efficiency of our current energy sources. There are some generation methods that can be developed which would be cleaner but we largely are just doing the same thing hoping for different results. As Nick put it, we probably need to invent our way out of this.
Spinning magnets and burning greasy residue is SO 1830's!
We live in an ocean of energy 24-7. It is there to be used, we just need to think in a new direction.
CHOOT UM!
I was thinking about buying a new car..... I can pay double the price for a hybrid that gets 4-5 miles more a gallon than the same car with a conventional motor...... Then the added factor of having to replace the batteries 5 years down the road actually makes the save the planet BS car way less cost effective..... Fact is the planet doesn't need to be saved, it's self regulated for BILLIONS of years according to scientists. The climate has been changing since the earth was formed either by chance or God depending on what religion you believe. Sorry LAGC, there no way man can stop climate change and your nonsense which means higher energy costs and control by gov't is just that nonsense so gov't can extract yet more money from producers to give to non producing scumbags.
Fact is the same gov't paid on the dole "scientists" were predicting a new ice age 30 years ago. They don't know shit about how the planet regulates itself.
Last edited by 1 Patriot-of-many; 09-20-2014 at 04:42 PM.
Correct me if I am wrong but this climate change thing started just before the end of the last ice age.
Gentlemen may prefer Blondes, but Real Men prefer Redheads!
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