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Future of fuel problem


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I was inspired to post this thread because of my response in one of sebbysteiny's recent threads...

Okay. I imagine a world without gasoline and other oil products to be run by hydrogen fuel sells, which, in the future look extremely viable and feasible.

Okay, so theoretically, we have solved the problem of no gasoline for cars.

 

Here's what I was just thinking about though:

Although the airline industry was damaged greatly after 9/11, aircraft are an extremely essential part of today's world (eg: transportation, military, recreation).

But what happens when petroleum runs out??

Fuel cells cannot be used to power aircraft!

What do we do? What options exist to enable use to power aircraft without oil??

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Okay. I imagine a world without gasoline and other oil products to be run by hydrogen fuel sells, which, in the future look extremely viable and feasible.

Okay, so theoretically, we have solved the problem of no gasoline for cars.

 

But what happens when petroleum runs out??

Fuel cells cannot be used to power aircraft!

What do we do? What options exist to enable use to power aircraft without oil??

 

Hydrogen is neither viable or feasible as a petroleum-for-fuel substitute. :) There is no free Hydrogen anywhere; it has to be produced using other fuels & therfore is a net-loss resource.

 

As to air travel I recommend airships using helium as a lifting gas & photo-voltaic electric powerd motors.:hyper:

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But what happens when petroleum runs out?

Coal to syn gas. syn gas to petroleum.

 

C + H20 + heat goes to CO + H2. Run Fischer-Tropsch for hydrocarbons or long chain alcohols.

 

http://www.fischer-tropsch.org/

 

Or run the syn gas over ZnO/Cu into methanol, then Mobil ZSM-5 zeolite to C8 aromatic gasoline. No problem. Montana alone has a near-surface coal seam 30 feet thick covering 1000 mi^2.

 

THE SKY IS FALLING!!! not.

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Hydrogen is neither viable or feasible as a petroleum-for-fuel substitute. There is no free Hydrogen anywhere; it has to be produced using other fuels & therfore is a net-loss resource.

 

Not so.

Pop a few solar cells on top of a generator, pass a current through water, and electrolyze a tank of water, and voila.... Hydrogen!

I have a google alert that emails me info on hydrogen fuel cells (hahahha), and it appears that producing pure hydrogen gas is becoming more and more economically feasible.

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Not so.

Pop a few solar cells on top of a generator, pass a current through water, and electrolyze a tank of water, and voila.... Hydrogen!

I have a google alert that emails me info on hydrogen fuel cells (hahahha), and it appears that producing pure hydrogen gas is becoming more and more economically feasible.

 

I saw a report last night on the hydrogen cars & making your own fuel at home by photo-voltaic fueld electrolosys and they said it would take a week of full sun on a large array to produce enough hydrogen to fill the car just once. Cars range was 100 miles.

Then you have to account for the energy used to make all those photovoltaic cells & their cost.

Call for Uncle Al...Uncle Al to the hydrogen help desk...:)

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But what happens when petroleum runs out??

Fuel cells cannot be used to power aircraft!

What do we do? What options exist to enable use to power aircraft without oil??

  • Fuel cells can be used to power aircraft, provided they’re electric motor-driven prop or ducted-fan propelled. This would require entirely new designs, but assuming that very high-power fuel cells and high density hydrogen storage can be affordably achieved (by no means a safe assumption), such designs matching the performance of current sub-sonic jet aircraft are not particularly daunting.
  • Hydrogen can be burned as a jet fuel. Many rocket engines, such as the main engines on the Space Shuttle, are hydrogen and stored oxygen-burning. Though no high-performance, air-breathing, hydrogen-fueled jet engine has to my knowledge been built, designs for such engines have been around since at least the 1960s - eg: the SABRE. Substantial redesign is still required, but performance is potentially much better than current jet engines.
  • Hydrogen, carbon, and oxygen can be made into methanol, an adequate but troublesomely caustic jet fuel. Hydrogen and carbon can be made into nearly any hydrocarbon, including gasoline and jet fuel, though I don’t think practical large-scale chemical processes have yet been developed for this.

None of these solutions address the problem of where to get lots of hydrogen, or if generating lots of hydrogen is a good idea. These problems and questions have been much discussed in these forums, so I won’t elaborate on them here.

 

Provided energy produces and vehicle engineers don’t badly mishandle planning for the coming decades’ needs, I think things should be OK.

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What options exist to enable use to power aircraft without oil??

 

Fortunately many options exist. We will not have to go back to helium filled airships. Although tad more expensive, Bio fuels (bio-diesel) could be fairly easily substituted. While there would be several technical issues (like gelling), but as long as we have farmers we good.

 

What is really going to hurt is the products made from oil. Less than half of the oil produced actually goes into fuel and lubricants (sort of, each unit of raw crude makes several products, of which, some of them are related to fuels and lubricants).

 

Rubber and Plastic is in just about everything. I know of no "bio" form of plastic. There isn't enough natural rubber to go around. I know of no replacement that is not created from crude in some part of the process. Not to mention the other hundred or so (gasses, foams, solvents, etc.)

 

Fuel is the least of our problems. Building the things we use today is. Computers, cell phones, and anything electronic. Cars, trucks, trains, airplanes, even bicycles. Appliances, furniture, houses, etc. They all need the products of crude oil to be BUILT much less run.

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I also saw something the other day saying that it takes more energy for a car to run on hydrogen per mile than for a car to run on gas.

 

I guess the difference is that the energy is pumped out of the earth's crust, or it is pumped out of the sun's solar heat which we already agree is cooking the earth these past few years.

 

However, the fact that farmers already efficiently use the sun's energy to grow the bio-mass necessary to produce ethanol means that less manufacturing needs to be done to create the solar cells and hydrolysis machines to create the hydrogen.

 

BTW, hydrogen is being stored in solid compounds until needed in the most modern of hydrogen powered cars, instead of using pure hydrogen from a pressurized cylinder.

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I'm back! yay. lol.

 

Anyway, I was watching a show on the science channel a while back.... I think it was about a trans-atlantic tunnel (which I do not think will happen for a long time [if ever]), but it introduced some interesting points.

 

Trains can be very efficient if we actually worked towards a more advanced system.

For instance, if you build a mag-lev system inside of a sealed tunnel, very quick transportation can be attained.

Since the train would be based on a mag-lev system, all train-to-track friction would be eliminated.

Now, mag-lev systems obviously exist and can achieve comprably magnificant speeds. Here's the fun part though. :eplane:

If you pump all of the air out of the tunnel, extreme speeds can be reached because almost all friction has been eliminated! (both train-to-track, and train-to-air friction) Air locks at the train "stations" will allow people to board the trains safely.

One could theoretically board a train in D.C., and go to work in L.A.

 

This could be very interesting. :eek2:

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Question: How much power is produced, on average, by square meter of PV?
A high-quality, clean-surfaced silicon photovoltaic cell has an efficiency of about 12%, generating about 120 W/m^2 at the equator. For estimating purposes, then, 100 W/m^2 is a good, round number. The world consumes about 10^13 W. So, to supply all of the worlds power, about 10^11 m^2 – a square about 320 km on each side, or about the area of an average-sized state, such as Virginia - of PV needs to always be pointed directly at the unobscured sun.
Question: How much power would be produced if 1/4 of the roof tops of america were converted to PV?
There are about 10^8 households in the US. Assume each household averages a modest 100 m^2 (This may be overstated – I’m currently sitting in a typical suburban single family home beneath about 200 m^2 of roof, but many Americans live in multi-unit homes with much less roof per houshold). The total rooftop area of America is – very roughly – 10^10 m^2, only 1/10th what’s needed to supply the world’s energy needs.

 

The practical details of how to do this – keep the panels clean, have sufficient are pointing Sunward at all times, distribute power halfway around the world during the night, or store energy, and how to satisfy all of the worlds requirements with electricity only, are very complicated. I seriously doubt that PV panels are a viable approach to the problem. However, these estimates give a rough idea of the requirements for a 100% solar world energy system, illustrating that some sort of near 100% solar world energy system is not beyond the realm of the likely. Many promising approaches in this direction are under serious development – hypography’s own Kayra comes to mind as having done a substantial amount of research in this area.

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No but they are part of the solution that I seek. We need many sources to make viable renewable power. So now, how about Hydro? Also what about the Sahara Desert (PV)? Wind? In a bit we will see about a few other (more esoteric) sources, of course one is not good enough, but many will suffice, and each can compensate for the draw backs of the other.

 

I think that Storing our power into Hydrogen fuel cells or other such would be good, as we can renew them.

 

Remember it is: Reduce, Reuse, Recycle. In that order.

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I'm back! yay. lol.

 

Anyway, I was watching a show on the science channel a while back.... I think it was about a trans-atlantic tunnel (which I do not think will happen for a long time [if ever]), but it introduced some interesting points.

 

Trains can be very efficient if we actually worked towards a more advanced system.

For instance, if you build a mag-lev system inside of a sealed tunnel, very quick transportation can be attained.

Since the train would be based on a mag-lev system, all train-to-track friction would be eliminated.

Now, mag-lev systems obviously exist and can achieve comprably magnificant speeds. Here's the fun part though. :hyper:

If you pump all of the air out of the tunnel, extreme speeds can be reached because almost all friction has been eliminated! (both train-to-track, and train-to-air friction) Air locks at the train "stations" will allow people to board the trains safely.

One could theoretically board a train in D.C., and go to work in L.A.

 

This could be very interesting. :hihi:

 

Evacuating the tunnel would be nearly impossible as the costs to produce such a sealed tunnel and train cars would be prohibitive in my sense of the situation. Instead blowing air through the tunnel in the direction of travel of the train would reduce the air friction to extremely negligible, but I think that tunnel itself would reduce the friction to negligible.

 

Now since you propose building a tunnel, would you build it underground? Who would tunnel this earth away? What happens in the case of an emergency in the tunnel (another good reason why evacuating the tunnel would be bad)?

 

If you have a tunnel why not have a metal tube which can allow mag tracks below and above and on the sides of trains to stabilize it's motion through the world. Better still, why not above and below tracks and forgo the tunnel. Then you only need a system of stringers to suspend the upper mag track so that the train can run on it and the people on the train still have a view.

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