Easy oil is already at its peak. New production is now from costly technologies like horizontal drilling and rock fracturing (fracking). Synfuels time has started. That admitted, any CO2 as carbon feed is a bad idea. It has low efficiency expressed as EROEI. The technologies with promise would be hydrous pyrolysis of underground kerogens, farm wastes, forest wastes, Plastic and paper from municipal wastes. Direct use of Jatropha or other vegetable oils could have a niche of suitability. As greenhouse conditions develop, one solution would be to use them for increased production of biomass on farms and in forests. This bio-mass can be treated as farm and forest wastes. More suitable varieties will develop and the process can be expedited by research.
If you're talking biofuels, biogas is pretty decent (highest energy yield per hectare of any biofuel). Biomethane can be used directly in CNG or LNG vehicles.
I once did the math for Germany (lost the .xls) and came to the conclusion that we could produce enough of it domestically without undue strain on availible land to power the transportation sector, if electrification is maxed-out.
Cars can be all-electric or CNG plug-in hybrids. Lorries too, but most cargo should be shifted to rail and waterways. Ships and planes could use LNG.
Natural gas is more plentiful and burns more cleanly than oil. IMO it would be a good idea to encourage its use in transportation more. It could then be replaced by syngas/biogas as decarbonisation progresses.
Last Edit: Mar 5, 2013 15:18:05 GMT 9.5 by Nuclear
Assuming this actualy does produce liquid fuel at a reasonable price given cheap electricity, maybe the best places to do synfuel from seawater initially, is in places where there is stranded hydro or geothermal near a coastline. Eg: the mouth of the Congo river or a Caribbean island.
This would make building the hydro or geothermal plants economic & provide cheap electricity to the local population that would be too small a market to make use of the resouce otherwise.
Can this technology be easily & cheaply scaled up or down to match the power supply?
"include Nuclear...I would have thought that was the last source we would want involved in this"
I suspect you think that because you have been hearing only the antinuclear talking points, which are at best half truths.
See eg: the fuss about the dangers of nuclear power. The grain of truth in that is that the danger from nuclear is not zero. The thing that is left out, making the fuss a deliberately misleading half truth, is that the dangers of anything else are at least as bad as if not far worse than nuclear.
Post by Roger Clifton on Aug 13, 2014 19:06:35 GMT 9.5
At the start of the thread, John Morgan referred to an analysis by the U.S. Navy that starts with hydrogen and CO2 then combines them in the manner of the Fisher-Tropsch process. But why start with hydrogen? The reliance on hot hydrogen in the 1920s F-T process was based on burning copious quantities of coal, whereas the copious quantity in this scenario is electricity.
Chemically inclined bloggers might know of a electrolytic pathway to liquid hydrocarbons that starts with wet CO2 and progressively removes oxygen instead of adding hydrogen. Then the summary of the process would look something like :
xCO2 +yH2O - z[O] -> H[CH2]xH
Direct electrolysis might allow some of the intermediate reactions to be induced in solution, emulsion, supercritical fluid or on a charged surface. Rather than try to create free oxygen in the presence of hydrocarbons, I wonder if oxygen could removed by adding an atom or group in a reduced state (such as HS-) and removing it later as an oxidised anion (such as SO4--) , to be refreshed electrolytically in a side process. That would amount to a "leaving group".
Any manufactured liquid fuel will require:- 1. Carbon 2. Hydrogen 3. Energy. We generally tend to deal with each in isolation. CO2 is the lowest energy level carbon, and therefore uneconomical unless reduced by free or cheap energy. Natural biomass is more suitable. Same with hydrogen in water. Electricity is a costly energy input for hydrogen if required to produce fuel. Biomass is a better input for hydrogen too. For low carbon input, we should user solar energy as in photosynthesis or nuclear energy before the conversion to electricity at low efficiency. So, for synfuel at sea, we must use the available biomass which has solar energy absorbed in the CO2 and nuclear energy as heat where required. Biogas is prepared from biomass and comparative economy of biological or chemical processes will have to be seen.
for synfuel at sea, we must use the available biomass ....
Jagdish … Photosynthesis is particularly good at polymerising carbon, outputting a three-carbon sugar then a six-carbon sugar, glucose. It doesn't use hydrogen as an intermediate, instead removing oxygen from water by oxidising PO3 to PO4 (ATP to ADP). However it is not efficient at harnessing solar energy. And for (in this scenario, aircraft) fuel production a faster process is needed.
Perhaps there is an electric way to replace the solar role in reducing the ADP back to ATP and powering up NADPH. Similarly a process would be needed to reduce the glucose to presumably hexane. Artificial photosynthesis is a developed field, but seems to be devoted to improving the collection of solar energy rather than replacing it.
Post by Clive Elsworth on Sept 25, 2016 3:18:36 GMT 9.5
The cost of SynFuel should come down if the cheap power from UK company Moltex Energy's Stable Salt Reactor (SSR) becomes a reality.
Here's a quote from Nuclear Energy Insider magazine: "The Levelised Cost of Energy (LCOE) of the SSR is estimated at $44.64/MWh for a 1 GW plant and this is based on highly-conservative estimates for Operations and Maintenance (O&M) costs"