Was reading this article today and it got me wondering how viable liquid coal powered vehicles will be in the future. The article of course says that with the price of converting coal into a liquid form coming down, that this will be the wave of the future…especially considering the vast amounts of coal there are out there in the world. They say it will also be (reasonably) eco-friendly.
So…are they right? Is this just a bunch of hype? Whats the straight dope on this technology…and for debate, is it a viable alternative to hydrocarbons for personal transport?
Yes, it’s a viable process. Liquid coal is a bit of a misnomer. It’s not as though they simply throw some coal in a blender and make it into a liquid. The hydrocarbons are chemically changed from coal, and you eventually end up with essentially gasoline. The downside is that it’s more expensive than extracting and refining oil, and it’s an incredibly dirty process. There is a whole bunch of nasty stuff in coal, including radioactive elements like uranium.
At some point the cost of oil will rise to the point where converting coal to gasoline will be economically viable. The U.S. has a ton of coal, and we could last a long time on coal-gas, especially if we stop using the coal for power plants. We would essentially maintain the status quo for longer than we could on just oil alone. Ultimately this isn’t a good solution though. At some point a power source that is much cleaner than hydrocarbons needs to be found.
In the old days gas (as in vapour) used to be extracted from coal by ‘baking’, the residual was moulded into nuggets of coke (black :-} ) which was used domestic heating.
Also in WWII the Germans made petrol from coal, and later the South Africans did the same.
The technology is old, and as Treis pointed out it is essentially manufacturing petrol.
I expect the technique could be made a lot ‘cleaner’.
Ultimately though, we really need to find a way of tapping existing ambient energy.
Coal-produced petrol would mainly be a way of converting/storing energy in a way convenient for vehicles. Probably what airplanes will fly on by the end of the 21st century.
That’s one way to look at it, but liquified coal is still a positive energy process. Meaning you get more energy out of the liquified coal then you used to make it, as opposed to batteries where you get less.
Cite? I’ve always understood it’s the reverse. (Or perhaps it’s that you get fewer calories from burning the resultant gasoline than you would from burning the coal itself – not clear on that point.)
The Fischer-Tropsch process makes sense for liquid fuel production only if you just can’t *get * liquid petroleum economically or at all, but you do have a lot of coal. Nazi Germany and apartheid-era South Africa popularized it, for instance.
I’ll have to look into it further and there might be a bit of a semantic issue here. My understanding is that you burn x amount of coal to power the process, and you get out y amount of gas. It’s my understanding that the energy in “y” is greater than the energy in “x”. Obviously if you look at the total energy of coal, that is the coal to power the process and the coal that turns into gasoline, you end up losing energy.
Gasefied goal/deisel fuel is the wave of the future because it shares a common engine with biodiesel fuel. No changes in automotive engineering required and we are sitting on huge reserves of both.
USAF has run some test flights in just the last few months on a B-52 with one pod fueled by synthetic JP-5. It did run visibly cleaner than the petroleum-derived stuff, although no measurements were taken (the test was of operability only).
It still does absolutely nothing to reduce greenhouse gas emissions, though - only the secondary stuff. In fact, the production process *uses * more fossil fuel energy, and simply delays the day when we run out of them while it contributes even more to global climate change.
Synthetic gasoline/diesel, made via the Fischer-Tropsch process (hydrogenation of coal) is not an efficient process. You have to make hydrogen (by reacting steam with iron), then react the coal with the H2 under high pressure. Why not just burn the hydrogen?
Actually, GM built a car that ran on powdered coal (IC) in the 1980’s-anybody have info on it?
Estimates of the cost of the process are $15-30 per barrel. In October of this year (2006) Montana signed a contract for the first US based production plant. F/T jet fuel was recently tested successfully in a B-52 bomber. In addition, there has been a recent development of a new, more efficient variation of the F/T process, discussed here