from Hacker News

Mazda has tested a synthetic fuel in an unmodified MX5 on a 1000-mile road trip

by socialdemocrat on 1/2/23, 1:45 PM with 201 comments

• by PaulHoule on 1/2/23, 2:08 PM

  There is no surprise that synthetic fuels work. They worked for the nazis in the 1940s and they still produce them in South Africa, Qatar and other places. In fact in a lot of ways they are better than today’s gasolines because they have a low aromatic and olefin content.

  The question revolve around affordability and sustainability. Most of the interest was driven by fears we would be running out of oil, now it is driven by fears that we won’t run out of oil.

• by kuschku on 1/2/23, 2:14 PM

  > it’s safe to assume that it’ll likely charge a hefty premium over traditional gasoline.

  > Also worth noting is that while, yes, this synthetic fuel appears to make vehicles slightly more efficient, it still greatly trails the efficiency of EVs. Consequently, vehicles using this fuel will likely always be more expensive to drive per mile than their electric equivalents.

  So why are we doing this again?

• by driverdan on 1/2/23, 2:10 PM

  It sounds like they ran it on straight ethanol. This isn't new or news. Many production cars can run on straight E in good weather. The mileage claim doesn't make sense though because ethanol is less energy dense than gasoline.

  It'd be nice if this blogspam linked to the source so we could verify details.

• by fsh on 1/2/23, 2:29 PM

  I don't think that this is a very good application for the technology. Compared to lithium batteries, synthetic fuels have much higher energy density, but much lower energy efficiency. Modern EVs achieve plenty of range, charge quickly, and the somewhat larger weight doesn't really matter in a vehicle, unless you want to race it.

  However, I am quite excited about using them for CO2-neutral long-distance flights. Being able to reach any place on earth in 24h is awesome, and there is simply no battery technology that can power a practical airplane.

• by api on 1/2/23, 2:21 PM

  Biofuels have at least two huge issues:

  The first is that solar PV has already well exceeded the efficiency of growing crops for fuel by multiples. Then there’s wind, nuclear, hydro, etc. Biofuels consume far more land than renewable and zero carbon ways of generating electricity. Even worse they consume fresh water. Electric generation consumes very little water by comparison.

  Secondly and related to this biofuels compete with agriculture for food. You frequently hear about using farm waste but there is only so much of that. Our machines use more calories than we do so try to scale that up and soon you are growing crops for cars. That’s a bad path to go down in a world where population is expected to peak as high as 11 billion. Much better to run machines on stuff we can’t eat than to set up a competition.

  The only good bet against EVs is in heavy and long range vehicles not cars. I am skeptical of electric trucks not because they can’t be done but because I am skeptical of our will to build out adequate charge infrastructure. But trucks account for a lot less liquid fuel use than cars so solving the car problem is a huge win. If we electrified light vehicles we could cut liquid fuel use by more than 50%.

  That doesn’t mean all car companies should totally cease ICE production though. There will still be some market for them into the foreseeable future. I expect EVs to take the bulk of the market though.

• by YesThatTom2 on 1/2/23, 2:10 PM

  I’m confused. This sounds like a good thing if the problem was an oil shortage, not CO2 pollution.

  Explain why they aren’t solving the wrong problem?

• by elif on 1/2/23, 3:16 PM

  1. Synthetic fuels still take a minimum of 110g CO2 to produce one MJ of fuel.

  2. Synthetic fuels still emit CO2, sox, nox etc. at the tailpipe

  3. "Synthetic" fuels still use natural gas as the feedstock in production.

• by marcus0x62 on 1/2/23, 2:17 PM

  1) How much of this fuel could be made at scale — how much of the type of agricultural waste they use is available worldwide?

  2) Petrol is great for passenger cars, but the world runs on diesel and fuels that are more or less equivalent to diesel, like Jet-1A. Can they make that?

• by greenthrow on 1/2/23, 2:18 PM

  Synthetic fuels should only be used going forward for hobbyists who want to keep classic cars going. They likely will be, and should be, expensive. Even if they are "carbon neutral" (unlikely as they still have higher costs associated with transportation than electricity), they still involve burning which always creates pollution, and any ICE requires lubrication and cooling which also today involves toxic chemicals.

  EVs are much more efficient and better for the environment beyond the most obvious and biggest benefit of not having a tailpipe that spews CO2 into the air.

  In other words; nobody should be hoping "carbon neutral fuel" is a path to continuing our status quo.

• by bl_valance on 1/2/23, 7:37 PM

  Toyota was also testing out synthetic fuels on their 3cylinder platform. I'm glad mfgs are testing different things and not just sticking to one thing just because everyone else is doing that. Interesting how Japanese carmakers are still not convinced on full electric, time will only tell. https://www.carsales.com.au/editorial/details/toyota-gr-86-n...

• by denton-scratch on 1/2/23, 2:08 PM

  > Simply put, the synthetic fuel operated much like normal gasoline would have, without the emission drawbacks of the latter.

  Hmmm. The fuel is hydrocarbons; so the emissions are at minimum CO2 and particulates.

• by dieselgate on 1/2/23, 5:14 PM

  This is a cool data point but I personally wouldn't call 45 mpg "staggering" - it's definitely good but not unprecedented by any means, many TDIs or smaller gas engines can get that on the freeway. The research into synthetic gasoline fuels is inspiring but at a certain point seem impractical and too-little-too-late. There are already well established "alternative" fueling technologies that are very easily accessible and likely cheaper.

• by Orangeair on 1/2/23, 5:58 PM

  Does anyone know what ever happened to Mazda's skyactiv thing? Was supposedly going to help ICEs be more fuel efficient by adding an extra stroke cycle with water? Seemed very promising, but I haven't heard anything about it in years.

• by elif on 1/2/23, 3:05 PM

  It is disgusting for the author to call the synthetic fuel "emission free"

  It's still a long hydrocarbon chain that breaks down into CO2 during combustion.

  This entire line of reasoning is avoided in the article, so I can only imagine it was sponsored by BP or SA.

• by mensetmanusman on 1/2/23, 2:52 PM

  Efficiency is a double edged sword. Hydrocarbons will always have a higher energy density than batteries due to physics, which is great when moving heavy things.

  Trucks are probably a good use case for synthetic zero or negative emission fuels.

• by IronWolve on 1/2/23, 4:29 PM

  I saw a video of an offgrid station that makes hydrogen from solar/water to power farm/work trucks. That seemed pretty green and cost effective in the long run.

• by cuteboy19 on 1/2/23, 1:49 PM

  I think heavy duty trucks and such will still work on gasoline even in an EV future. So why don't these companies try to solve that problem in a carbon neutral way?

• by mrcwinn on 1/2/23, 2:07 PM

  I support anything that keeps the wonderful Miata just as it is. (Okay, fine. I more so support anything that keeps the earth healthy and sustainable.)

• by LP3L on 1/2/23, 11:37 PM

  Can we just use Ethanol with hybrid system? I mean, in ethanol are very common fuel, if we combine this with hybrid, thas a win win IMO.

• by account_created on 1/2/23, 2:16 PM

  Is this the one that was discussed on Joe Rogan by Randal Carlson recently?