Talk:Synthetic fuel

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[edit] How long will synfuels last

This statement needs justification: "While at present synthetic fuel are primarily produced because of subsidies, they are a proven technology that offers the potential to solve the energy crisis due to the depletion of oil (Hubbert peak), at least for the next few hundred years." --Nagle 20:20, 13 March 2006 (UTC)

The following is all straight from EIA data: current oil use for energy is at ~160 quadrillion Btu/year and coal is at ~90 quadrillion Btu/year [1]. World reserves of coal are 1081 billion short tons [2]. Coal energy density ranges widely, but typically between 11,500-13,000 Btu/lb for bituminous/anthracite and 6,500-8,200 Btu/lb for lignite/sub-bituminous. If coal synfuels replaced all oil tomorrow at an 80% conversion efficiency, and coal averaged 9000 Btu/lb, coal use will have to be ~16 billion short tons per year, calculated as ( 160 quadrillion Btu / 0.8 + 90 quadrillion Btu ) / ( 2000 lb/ton * 9000 Btu/lb ). If energy usage does not increase (unrealistic, I know, but nobody can predict the rate of increase either), coal will be sufficient for 1081/16 = 70 years. So it's not "hundreds", but "close to a hundred" ;) On the other hand there is still plenty of oil, plus other untapped sources such as shale... so it basically works out that without major increases in demand coal synfuels can "pick up the slack" for well over a hundred years. ObsidianOrder 00:10, 14 March 2006 (UTC)

This is an impressive conversion efficiency you are suggesting, the efficiency of a gas to liquids plant is significantly greater than that of coal to liquids and yet a gas to liquids can only acheive 50% efficency. How is coal going to get to 80% efficiency?

This article [3] describes both Syntroleum's GTL and Sasol's CTL processes to have 60% energy efficiency today. Other studies show CTL gasifier efficiency close to 80%. and suggest that co-generation can bring overall efficiency close to that mark. I am assuming some technology improvements (iron or iron-cobalt nanocatalysts) and some increase in efficiency from scale-up. In any event, since petroleum consumption above is listed as pre-refinery energy content, you only need to look at the efficiency of a CTL plant relative to that of a petroleum refinery which is typically around 90%. When running GTL/CTL, you can synthesize methanol or dimethyl ether instead of gasoline, and burning those in an internal combusion engine is considerably more energy efficient (up to 15-20%, although diesel is even more efficient), so that would mostly make up for the inefficiency of conversion. Finally, mining coal (particularly open-pit) requires less energy than extracting oil. Because of all these factors, 80% relative energy efficiency is conservative, on a "well/mine-to-wheels" basis. ObsidianOrder 01:14, 17 October 2006 (UTC)

[edit] Time magazine article

The last external links from TIME magazine doesn't actually talk about synthetic fuel, but rather, a ploy by some corporations in the US to abuse regulations so they can benefit from synfuel tax break without having to actually produce "real" synfuel themselves. I think this link should be deleted because it doesn't provide more information about the fuel itself and tends to make readers think synfuel is not a legitimate technology.

Certainly not. On the contrary, the article should be expanded to point out the differences between "tax scam" and "legitimate technology". -- Petri Krohn 15:10, 20 April 2006 (UTC)

Not all synfuels are what they purport to be. Reference to continuing widespread industry corruption surrounding synfuels would be appropriate and responsible. There should be a link to the industry lobbying group Council for Energy Independence. --Panglos 16:59, 19 April 2006 (UTC)

[edit] Clarification

What price would crude have to be at for synthetic fuel to become economically viable if all other factors are constant? —The preceding unsigned comment was added by 192.246.226.180 (talk • contribs).

That is highly dependent on the exact location of the synfuel facility. The range is probably $35 to $70 per barrel oil, at present coal prices. There are locations in China which are close to the bottom of that range, and locations in the USA which are in the middle of that range ($55-60 for some sites in Wyoming). ObsidianOrder 23:49, 25 May 2006 (UTC)