Has converting natural gas to gasoline been done on a commercial scale? I have read about this being a possibility, and there were theorists who claimed it could be done much cheaper than gasoline made from petroleum. I’m pretty sure people have experimented with it, but did anything come of it?
Why when you can run the vehicle very well directly off the LPG?
LPG is propane, not natural gas.
You can also run a vehicle on CNG, or compressed natural gas.
The Fischer-Tropsch process has been around since the 1920s. The problem is that it’s not cheap. Companies have experimented with variations on this process but haven’t been able to get the costs down to the point where it’s even worth bothering trying to go full scale with production.
There’s a company named Siluria Technologies that claims to use a different process that promises to convert natural gas into gasoline much more cheaply. They’ve built a couple of pilot plants, but mostly all we have are the company’s claims so far, and these are basically put forward to attract investors. They haven’t gone into full scale production anywhere yet, at least not as far as I can tell from poking around on google. Whether or not they can deliver on their promises remains to be seen.
There’s a wikipedia page about them but it doesn’t have much info.
Is that process worth it if it’s commercialized? I would think that it’d have to be pretty damn efficient, liquid gasoline is more energy dense than natural gas compressed at the levels typically found in CNG cars, but I would think the differences aren’t so great as to making converting from natural gas to gasoline worthwhile unless the conversion itself was very efficient and cheap.
It’s commercialized, GTL (gas to liquids) in general that is. Shell’s Pearl GTL plant in Qatar is the biggest with an output of 140k bbl/day of liquid petroleum product besides condensate (like ethane), so equivalent to a decent sized though not huge refinery. That plant puts out distillate product (diesel, kerosene etc) but it isn’t fundamentally harder to produce gasoline.
Shell cancelled or at least postponed a plan for an even bigger plant of that type in the US. The economics aren’t as favorable since the drop in oil prices of the last few years, even though NG prices have dropped too. The economics of burning CNG and LNG in cars, trucks, ships etc has also deteriorated lately despite lower nat gas prices. The relationship of oil to gas prices tends to be determined by users for whom there isn’t a big extra upfront capital cost to use gas instead of oil or it’s even the other way around. So lower fuel prices in general tend to make the extra cost of systems to distribute and use CNG/LNG, or big plants to turn nat gas into easy to use diesel or gasoline, harder to justify.
The synthetic fuels plant at Motunui in New Zealand did produce gasoline (petrol) from natural gas and ran from 1986 to 1999 but ceased producing petrol when market prices dropped. It now produces methanol after being mothballed for some years.
You can run the vehicle quite readily off CNG or LNG. You can do a conversion for just a few thousand bucks in parts, or Honda will sell you a car that uses CNG from the factory for a few thousand dollars more.
The extra parts are basically just a different manifold for the fuel injectors, a gas line, a modified engine control unit, and a special high pressure tank. The engine and the rest of the car are the same. I suspect if natural gas vehicles were common, they would cost the same or only slightly more than their gasoline equivalent.
For comparable range and fuel density, you may want to use LNG in a semi truck. Or you’re going to need a lot of CNG bottles. I read that the total cost is a little cheaper to use CNG, but LNG is almost as energy dense as gasoline. Either way, the cost of the vehicle is a little bit more because it’s either an armored, high pressure set of fuel tanks, or a cryogenic vessel that can hold the liquified natural gas. The downside of LNG is you can’t store the vehicle inside - if the vehicle sits for a long time, the LNG boils and need to be vented. This is an emissions issue, as well, since methane is a worse greenhouse gas than CO2.
There’s some real potential for a carbon free economy here, since it’s far easier to store and use methane than it is to use hydrogen, and you can convert hydrogen to methane just by adding CO2 (which you could have extracted from the atmosphere for a closed loop)
Main drawback is that if you have X units of energy, you’re going to lose about 30% even with high efficiency electrolysis, and another 10% from Sabatier, and then you have to compress the resulting methane, and then when you burn it in a piston engine, you lose another 60-70% of the energy. So the net efficiency is dismal (~20% or less). Far better to charge up batteries with electricity generated from carbon free electricity sources (solar, nuclear, wind, hydro) and use it directly.(which can be 80% or better, including transmission line and charging losses)
Yes. Few are still operational
Coal to Liquids has been more popular in the past. Most of the processes rely on converting the natural gas (or coal) to syngas (a mixture of CO, CO2, H2 and Water). The syngas is then converted to oil (hydrocarbon liquids) using the Fisher Tropsch Process. This is how Hitler made his fuel when the oil supplies to Germany was cut off.
The syngas can also be converted to Methanol which in turn can be converted to Gasoline or used directly as a transportation fuel, dehydrated to DME which can replace Diesel or converted to Olefins (used for making plastics) or a range of acetyls.
It’s hard to make drilling + separation
- chemistry + purification cheaper than just drilling + separation. The economics can work when you have a large oil/NG price gap. Natural gas can be hard to transport, so it can sometimes be cheaper to convert it into a more result transported liquid. Note you can just refrigerate it into a liquid (for a cost), so you’re competing with that.
So we see GTL in places like Qatar, with lots of dry gas and no pipelines.
People talk about small-scale GTL for stranded gas at new wellpads, off-shore, Alaska, but the economics for chemical princesses get even dicier when you scale down.
That is a tad confusing.
drilling + separation + chemistry + purification --------> This how oil refining works today with Fluid Catalytic Cracking as the Chemistry in the USA and Hydrotreating in Europe. FCC is to make more gasoline from the oil and hydrotreating is to make more diesel.
I think you are saying synthesizing gasoline from natural gas is too expensive, which I agree.
Less explode-y.
What’s the risk differential? A ruptured LPG tank can explode as well as a ruptured gas tank, it just takes the right concentration of fuel:air. I would agree that the LPG probably mixes more easily, but how much of a difference does this make? You could armor the tanks and put them closer to the center of the vehicle to reduce this risk - it’s not like car manufacturers take every possible mitigation factor with gasoline tanks.
No categorical statements on such a topic are likely to be correct, anyway aren’t in this case. Just because it takes investment in a GTL plant to easily feed the fuel, natural gas, into the existing distribution system doesn’t mean it’s less economical that building a new infrastructure to distribute LNG or CNG and provide the necessarily fuel systems on the cars, trucks or ships. The answer is ‘depends’. And just as GTL plants don’t look as attractive right now as when Shell built the Pearl plant in Qatar and actively considered a similar but larger one in Louisiana… it’s not as favorable right now to convert trucks or ships, let alone personal vehicles to CNG or LNG right now.
There’s no simple logical equation that means the GLT method is less economical than adapting NG directly as transportation fuel, again depends. Likewise as mentioned gasoline (though diesel fuel somewhat less so) is quite dangerous stuff if one were to obsess about the things that could happen at gas stations, but they rarely do. When it comes to LNG or CNG people are relying more on imagination.