Cost to synthesize non-fossil fuels using Fusion driven Fischer Tropsch.

[Duke Leto]

Here’s an interesting question for FF-iacs out there. I’m trying to calculate the cost per unit of synthetic gasoline and synthetic methane based on the Fischer Tropsch process with biomass as the input. I think the system would go like this:

Biomass -> Charcoal -> Water Gas (C + H2O -> H2 + CO) -> Fischer Tropsch to make Methane. Maybe the charcoaling phase is not needed.

I think the cost of Charcoal is the cost of the Biomass + the time it takes to burn it down + cost of the kiln. I’m figuring $nil + x Hrs + trivial kiln costs means it’s free as long as the biomass is. Maybe Bamboo or Kudzu would be the most effective bulk biomass generator.

Anyway, let’s say the charcoal comes in at $50 per ton (Slightly less than Coal) and the water is distilled using FF and practically free per ton. Then the cost of the water gas process to produce CO and H2 is going to run to 7 cents, ASSUMING I’m reading this College paper on the cost of Water Gas production right, which I doubt I am.

So let’s say 50 cents.

Now to get Fischer Tropsch to happen you have to heat this stuff to 350 degrees centigrade. The cost of the fusion power to do this is going to be whatever the specific heat of H2 + CO is , lets say about 1 for shits and giggles, times $0.50 + ~330 * 1.163E-06 kWh per calorie * $0.005 per kWh * 800 kg * whatever the hell the density of the stuff is, lets say 1 liters per kg. Probably all underestimates. But what we then have is $0.51 per liter of hydrocarbon, or $1.96 per gallon plus some Carbon Monoxide pollution.

This can’t be correct, but that’s why I’m submitting it to you.

What about cutting out the middle man and doing H2O + atmospheric CO2?

The point here is can atmospheric CO2 and H2O be made into gasoline and methane economically? With or without recourse to Photosynthesis? Thus making fossil fuels not worth collecting?

Discuss.

[JimmyT]

This may not answer the question, the question being an economic one. But South Africa decided several decades ago to limit their economic dependence on imported oil. They had extensive coal reserves but little oil. So much of the country’s liquid hydrocarbon needs are met (NOW) by synthetic fuel made by the Fischer-Tropsch method using Lurgi gassifiers. The name of the state run company is SASOL.

[dennisp]

I’ve seen other estimates that ended up with similar numbers.

You can take CO2 out of the atmosphere directly using “artificial trees”…google for “artificial trees CO2,” or ctrl-f on my climatecolab entry here:
http://climatecolab.org/web/guest/plans/-/plans/contestId/3/planId/12803

Cost is estimated at $150/ton carbon initially, dropping to $20 at scale. Each absorbs as much CO2 as around a thousand natural trees. So if our numbers are right, we could drop your estimated price about in half, and dedicate a lot less land area to the task.

One additional step is required this way, to convert CO2 to CO. Here’s one method of doing that:
http://www.science20.com/news/turning_carbon_dioxide_into_fuel_using_solar_power

Obviously with cheap fusion we don’t necessarily need to restrict ourselves to sunlight to power this.

[Duke Leto]

Don’t need sunlight for the Artificial Trees either…

[dennisp]

Here’s another method of turning CO2 to CO:
http://www.wired.com/science/discoveries/news/2008/01/S2P

I also found this on wikipedia:
http://en.wikipedia.org/wiki/Bosch_reaction

Also worth noting: the cost estimates for the “artificial trees” assume current electricity costs. Really cheap power would make it even better. I don’t know how much of the cost is energy, but if we assume half we’re talking fifty cents for a gallon of gas.

This article says that 250,000 artificial trees could absorb all current emissions.
http://news.bbc.co.uk/2/hi/science/nature/2784227.stm

Transportation accounts for less than half of CO2 emissions, so 100,000 artificial trees would be about the right ballpark for supplying all vehicle fuel. That compares pretty favorably to the number of windmills people are talking about building. According to a paper I read, one of these artificial trees would reduce net emissions about as much as 500 similar-size windmills.

In short, combining this technology with focus fusion would obsolete the entire fossil fuel industry pretty quickly. We’d still need the pipelines and gas stations, and probably refineries, but that’s it.

[Wesley Bruce]

Biomass can be turned into Methane via an anaerobic digester. Just add water and bacteria to biomass and exclude oxygen. Its the most efficient biofuel. The bugs are self powering and reproduce the only catch is that you must balance the nitrogen to carbon ratio to about 20:1 carbon/nitrogen. That’s easy add urea, urine or manure.

Biogas results: that’s a mix of methane and CO2. Its incompressible because of the CO2. Scrub that out with lime and you have natural gas.
An catalyst and refrigerator will turn methane into ethane. The reactions are all exothermal but the biogas digester must be kept warm to work. Insulation in higher latitudes will do; heaters are required above the Arctic circle. The ethane reaction is used in industry to heat and drive other reactions. Ethane can be used in cars with a pressure tank, adding a little propane and chilling a little increases ethane’s usability. The mix gels in the tank reducing pressure concerns.

Fischer–Tropsch Synthesis can be used to make oil but its several steps backwards to go forwards and you have less control of the products. Adding in methane or ethane to the Fischer–Tropsch Synthesis increases the productivity and control. There are other pathways that allow heavier hydrocarbons to be synthesised direct from methane and ethane mixes. Some resemble fuel cells.

So far no energy input is needed up to ethane.
Heat and electricity from the the Focus Fusion unit would be used to cook the limestone mud that results from the lime wash of the biogas back into lime. This regenerates the lime. Heating ethane under pressure with a proton conductor or catalyst makes the heavier hydrocarbons. The catalyst strips off a few hydrogen atoms and the carbon carbon link form making a longer chain hydrocarbon. Catalyst type and geometry governs the Octane number or level of branching in the hydrocarbon result.

These processes produce hydrocarbons that need need less refining than crude oil but it will need some. Heat and power from the FF unit could drive the refining. Often oil refineries are powered by running the heavy oils and tars through a furnace and burning them. A FF biofuel system and refinery would produce very little tar so the power from the FF unit is needed.

To be viable you will need more than one chemical pathway and catalyst combination out of your methane ethane stage. Most fuels are a mix of hydrocarbons and related compounds so if you don’t want huge flammable storage you will need simultaneous parallel production of the mix.

A focus Fusion unit can also provide heat and power to refine cellulose for celluloseic ethanol and to heat the stills. It can also power illumination of seals vats of algae oil and refine the product.

It should be noted that there is a way to make alcohols and sugars and even protein from the Methane ethane mix. Add Carbon monoxide in the presence of the right catalysts. Its very very energy hungry and the sugars are pretty basic but If we have fusion we can make food in theory. However simply powering a greenhouse or hydroponics unit will work better and produces much more variety.
With unlimited energy at a low price you can do it all.

[Tulse]

Wesley Bruce wrote: It should be noted that there is a way to make alcohols and sugars and even protein from the Methane ethane mix. Add Carbon monoxide in the presence of the right catalysts. Its very very energy hungry and the sugars are pretty basic but If we have fusion we can make food in theory. However simply powering a greenhouse or hydroponics unit will work better and produces much more variety.

But this process sounds like it would much faster than growing things, and would be far more tolerant of environmental conditions. It might make sense in very impoverished situations, such as interplanetary spacecraft or lunar colonies, where one could simply “recycle” food.

[JimmyT]

There is a caveat to biodigestion. The microorganisms involved require warm temperatures. Warmer than we have here in North America during the half of the year. So you have to provide some heat source to warm the digester, and this somewhat lessens the benefit. They use this method extensively in India where the temperatures are somewhat warmer year-round.
Now, if we only had some source of low level waste heat to do that. Hmm…..

[Wesley Bruce]

JimmyT wrote: There is a caveat to biodigestion. The microorganisms involved require warm temperatures. Warmer than we have here in North America during the half of the year. So you have to provide some heat source to warm the digester, and this somewhat lessens the benefit. They use this method extensively in India where the temperatures are somewhat warmer year-round.
Now, if we only had some source of low level waste heat to do that. Hmm…..

Several research teams and commercial users have done biogas in Europe and north America including Canada and Alaska. The key is insulation and in some cases putting the thing in a simple greenhouse. Where some of the methane is burned on site to power something the waste heat can be used to heat it to optimal temperature. Many new sewerage works built today are Anaerobic. Some built in Asia and France are inside glass skyscrapers. Given these elements and lots of spare heat from an FF unit it should work well.

[Wesley Bruce]

Tulse wrote:

It should be noted that there is a way to make alcohols and sugars and even protein from the Methane ethane mix. Add Carbon monoxide in the presence of the right catalysts. Its very very energy hungry and the sugars are pretty basic but If we have fusion we can make food in theory. However simply powering a greenhouse or hydroponics unit will work better and produces much more variety.

But this process sounds like it would much faster than growing things, and would be far more tolerant of environmental conditions. It might make sense in very impoverished situations, such as interplanetary spacecraft or lunar colonies, where one could simply “recycle” food.

Actually most of the food systems for the moon and mars is well underway. We even have plants that are optimised for growing in zero g. See apogee and Perigee wheat. http://iss.cet.edu/farming/activity/plandes/research/popupinfo/var/4_4.htm
They grow well on the international space station or a storeroom sized farm. They’re growing peas regularly up there but the crew aren’t allowed to eat the lab specimens.
The seed list for the moon and mars are several years old and constantly up dated. Fish, chooks and goats are also on the list. Or is that on the crew list?
The original research into abiotic production of food comes from a cold war project to see if the survivors of World War 3 could feed themselves in a nuclear powered bunker.
Recently some food technologists from France hosted a meal in a restaurant in Singapore that was fully abiotic. Made in the lab from all unnatural ingredients. Its not essential; the world isn’t short of food but useful to know that such things are possible. 😉 With abundant cheap energy many things become possible.

[Breakable]

Wesley Bruce wrote: ..the world isn’t short of food…

While this is off-topic, do you have a reference for it?
I am wondering because I like to state myself that there is not enough resources to supply the need of the world and reducing inequality would not resolve current issues.

[Matt M]

The Navy is researching pulling CO2 from sea water, combining it with excess power from their nuclear
reactors and producing jet fuel at sea.

It would be expensive. But, it would replace expensive and vulnerable fuel ships.

[Tulse]

Matt M wrote: The Navy is researching pulling CO2 from sea water, combining it with excess power from their nuclear
reactors and producing jet fuel at sea.

It would be expensive. But, it would replace expensive and vulnerable fuel ships.

If the process uses actual excess power, would it be that expensive? I would think the main cost would be power.

[Author]

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