Electric cars vs gas-to-liquid technology

[Surlethe]

Good idea the trains.
One remark: nuclear power isn't viable. There doesn't exist enough uranium to drive the world energy.
Wind. Solar. Bio fuel. Geothermic.
In a combination of.

Please provide more details and analysis.

By the way, you're incorrect about uranium, according to a 1983 paper: Cohen, Bernard L. (1983). Breeder Reactors: A Renewable Energy Source. American Journal of Physics 51(1). He says there are billions of years' worth of uranium, at present total energy consumption levels, locked in the Earth's crust. Even if you up consumption by three orders of magnitude.

[Sky Captain]

And of course there is also thorium which is about three times more abundant than uranium and potentially cold turn out to be better nuclear fuel than uranium. From what I have read thorium fuel cycle produces much less long lived waste products than uranium cycle so greens also would be more satisfied.

[Surlethe]

And of course there is also thorium which is about three times more abundant than uranium and potentially cold turn out to be better nuclear fuel than uranium. From what I have read thorium fuel cycle produces much less long lived waste products than uranium cycle so greens also would be more satisfied.

What have you read? Do you have any references?

[Sky Captain]

And of course there is also thorium which is about three times more abundant than uranium and potentially cold turn out to be better nuclear fuel than uranium. From what I have read thorium fuel cycle produces much less long lived waste products than uranium cycle so greens also would be more satisfied.

What have you read? Do you have any references?

That info comes from what I have read in energy from thorium forum.

http://www.energyfromthorium.com/forum/

[Tolya]

A train can never outrun a 737, but if a much larger network with electric car transportation were offered, it could take the place of the car in long distance auto trips.

Not quite true. While the actual flight is very quick, you have to add other time consuming factors: like the bloody necessity to appear at the airport a full hour before boarding the plane. Then add another 20-30 minutes for boarding, taxing, takeoff. After landing you still need to claim your baggage, which takes additional time.

It of course depends on distance - the greater it is, the more obvious the advantage of air transport becomes.

[Qi__]

Good idea the trains.
One remark: nuclear power isn't viable. There doesn't exist enough uranium to drive the world energy.
Wind. Solar. Bio fuel. Geothermic.
In a combination of.

Please provide more details and analysis.

I have checked the articles and it seems you are right, there is enough uranium to hold for thousands of years with the world's energy consumption.
That is, if we have enough energy to mine it.

[Surlethe]

You didn't answer my request to please provide more details and analysis. Your posts are short and have no substance.

[Surlethe]

That info comes from what I have read in energy from thorium forum.

http://www.energyfromthorium.com/forum/

Can you cite some specific threads and posts, please?

[Starglider]

I have checked the articles and it seems you are right, there is enough uranium to hold for thousands of years with the world's energy consumption.
That is, if we have enough energy to mine it.

If mining of coal manages to be energy positive (and horrible low-quality brown coal at that), how could uranium mining possibly fail to be energy positive? Yes it needs a bit more preparation before you can use it, but uranium ore has thousands of times as much energy by mass.

[Lusankya]

A train can never outrun a 737, but if a much larger network with electric car transportation were offered, it could take the place of the car in long distance auto trips.

Not quite true. While the actual flight is very quick, you have to add other time consuming factors: like the bloody necessity to appear at the airport a full hour before boarding the plane. Then add another 20-30 minutes for boarding, taxing, takeoff. After landing you still need to claim your baggage, which takes additional time.

It of course depends on distance - the greater it is, the more obvious the advantage of air transport becomes.

I believe that about 4 hours (train time) is where people begin to favour planes over trains.

But the advantage of Duchess's idea of rail-road trains is that when you get to the other city you have your car with you, which (aside from the cost) is a significant advantage in taking your car somewhere. And of course, if the price was decent, I'd much prefer a 24 hour train ride to 24 hours of total driving time (which would probably end up taking 2-3 days, given rest breaks, sleeping, etc.).

[Qi__]

If mining of coal manages to be energy positive (and horrible low-quality brown coal at that), how could uranium mining possibly fail to be energy positive? Yes it needs a bit more preparation before you can use it, but uranium ore has thousands of times as much energy by mass.

This article explains about that concern.

As it says, the problem doesn't seem to be any shortage of nuclear fuel per se, but that the oil and gas used in its extraction and processing do look set to run-short, and this will impact on the nuclear industry just as it will on all other aspects of life that are underpinned by these resources.

[[R_H]]

I believe that about 4 hours (train time) is where people begin to favour planes over trains.

But the advantage of Duchess's idea of rail-road trains is that when you get to the other city you have your car with you, which (aside from the cost) is a significant advantage in taking your car somewhere. And of course, if the price was decent, I'd much prefer a 24 hour train ride to 24 hours of total driving time (which would probably end up taking 2-3 days, given rest breaks, sleeping, etc.).

That exists in Europe. Sometimes commercial trucks are transported like that too.

[Starglider]

As it says, the problem doesn't seem to be any shortage of nuclear fuel per se, but that the oil and gas used in its extraction and processing do look set to run-short...

Neither of those are necessary. The mining equipment that isn't already electrified (e.g. open cast mining machinery) can be, as can the trains that transport the ore. International shipping can be done with nuclear cargo ships. Nuclear-produced hydrogen can be used where electric power is impractical. These solutions are more expensive now, but they won't be if oil and gas prices keep climbing. The only question is whether the price rise will remain steady enough for an orderly switchover to occur - and whether ignorant anti-nuclear zealots will manage to sabotage mankind's energy security any more than they already have.

[Gilthan]

That info comes from what I have read in energy from thorium forum.

http://www.energyfromthorium.com/forum/

Can you cite some specific threads and posts, please?

I'm not sure he should have to take the time to formally back up each post with specific references when AFAIK nobody is arguing against his specific points. Most posts in most threads aren't that formal. However, I'll do it:

For the relative abundance of thorium, just google geological survey thorium.

http://minerals.usgs.gov/minerals/pubs/ ... -thori.pdf
http://minerals.usgs.gov/minerals/pubs/ ... 690496.pdf

Thorium is three to four times more abundant in earth's crust than uranium, almost as much so as lead overall, while found at elevated 1-10% concentrations in monazite sands. Welding-grade thorium nitrate sells for $5.50 per kilogram, a level of inexpensiveness illustrative of its ease of obtaining, even though high-purity thorium metal or oxide is such a tiny niche market today that the few suppliers sell it for much more.

With the Th-232->U-233 cycle, thorium reactors by default use the bulk of the thorium in their fuel, unlike conventional uranium reactors (except breeder reactors) which are primarily based on having enriched and then fissioning the mere 0.7% of natural uranium that is U-235, mainly just discarding the bulk of the U-238.

The long-term radioactivity of spent fuel from the thorium cycle is only a very tiny fraction of that from the uranium cycle, with far less high-level waste requiring long-term disposal (though neither really causes any major harm to public health in practice).

Figure 1 in the following shows that well:

http://lpsc.in2p3.fr/gpr/english/NEWNRW/NEWNRW.html

(Actually, though, the figure there for the time before spent fuel is less radioactive than the original ore could make someone vastly overestimate the relative radioactivity of deeply buried waste compared to radioactivity in nature, as under a billionth of the total uranium and thorium in earth's crust is mined a year, with total U+Th being 7.8E-6 of the 2.77E22 kg crust).

These particular advantages are more merely mild advantages than they might seem, though. Uranium fuel is already only a tiny component of total nuclear electricity generation cost, making the still greater inexpensiveness of thorium nice but not critical. As for the relatively lesser long-term radioactivity of spent fuel, the greens who are opposed to nuclear power don't tend to be the type who'd be learning detailed info or understanding anything mathematical anyway.

Still, there are some other arguments for thorium reactors too:

http://energyfromthorium.com/lftradsrisks.html

The biggest factor determining whether thorium reactors become more common is the economics versus uranium-cycle reactors, and that could go either way, some arguing that thorium reactors could be cheaper, although the uranium-cycle has so far the hefty financial and development advantage of far more experience with it. Both are affordable methods of relatively cleanly generating electricity, either capable in principle of meeting any portion of humanity's energy needs for eons.

[Surlethe]

That info comes from what I have read in energy from thorium forum.

http://www.energyfromthorium.com/forum/

Can you cite some specific threads and posts, please?

I'm not sure he should have to take the time to formally back up each post with specific references when AFAIK nobody is arguing against his specific points. Most posts in most threads aren't that formal.

The problem is not not formally citing his sources in every post, the problem is the intellectual laziness inherent in saying, in response to "How do you know this?", "See here" without providing any directions to actual sources or bothering to repeat their arguments or facts in some detail.

However, I'll do it:

Thank you.

[Sky Captain]

Oh thanks Gilthan for your input.

Here is some additional info regarding thorium fueled reactors and fuel cycles

A comparison between current power reactors an a thorium fueled liquid fluoride reactor.
http://thoriumenergy.blogspot.com/2006/ ... orium.html

A comparison between amount of waste products generated in thorium and uranium fuel cycles.
http://thoriumenergy.blogspot.com/2007/ ... ssing.html

Article in world-nuclear about thorium
http://www.world-nuclear.org/info/inf62.html

[The Duchess of Zeon]

Thorium in the molten salt cycle is going to be a great option for the future, but really the actual solution to our long-term energy difficulties will I think be in uranium recovery from the ocean, which is currently being worked on. Either one however can be used as fuel for molten salt reactors, which have advantages in that they can be refueled while operating, and have very high potential rates of fuel reprocessing (which should really be called "nuclear fuel recycling" for publicity purposes).